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The coastal cliffs around the Roses Lighthouse (Cap de Creus, Mediterranean Costa Brava) display deformation structures generated during the emplacement of a syntectonic granodiorite and associated rocks (quartzdiorite enclaves and leucocratic dykes). These rocks were subjected to shearing and spectacular shear zones are present, which have been object of several scientific publications. The outcrops are considered of international high scientific value, being regularly visited by researchers and students from several European universities. In 2005, the site was included in the Geosite Inventory of Catalonia, but it does not have any special protection yet, despite decades of efforts to claim the need for protection and conservation in front of the constant deterioration and loss of outcrops due to strong urban and touristic pressure. A project of restoration, access improvement, and dissemination of geological values was finally executed between 2020 and 2021. The Roses case study leads us to the remark that urban and periurban geosites offer a good opportunity for promoting geological research, education, and tourism, provided its protection based on geoconservation criteria and a strong sustainable conservation management plan. We wish to thank Joan Esteve Danès, former councilor of the Roses town council, for his concern and awareness on the importance of this geosite and his involvement in dynamizing the project. We are grateful to two anonymous reviewers for their useful comments. Thank you also to Manuel Monge for providing a useful review of a previous manuscript presented at the ProGEO SW Europe Regional Working Group Virtual Conference on Geoconservation (March 2022). ED received funding by the Roses town council (Ajuntament de Roses—UAB contract GJ514392).

With proven reserves of 9.836 × 1010 m3, the largest known natural gas reservoir among terrigenous basement rocks has been discovered within the granitoids of the northern Qaidam Basin. Due to their high heterogeneity, the genesis of basement reservoirs remains unknown. Herein, the structure of the weathering crust in granitoids and their potential controlling factors on the reservoir development mechanism are discussed using a multidisciplinary approach based on data from cores, thin sections, scanning electron microscopy (SEM), conventional and imaging logs, and physical property and major elements analyses. Moreover, the classification standard of the weathering crust structure is established. The dissolution belt holding diverse reservoir spaces accounts for more than 50% of the total porosity, while the disintegration belt is the main context for the development of cleavage fractures and crack fractures. The original pores exist mainly among the crystal grains of quartz and mica, while the secondary pores and fractures were generated by the alteration of aluminosilicate minerals as well as biotite or hornblende. The quality of these reservoirs is controlled by their mineral composition, tectonic uplift, faulting, and paleogeomorphology. The femic granitoid is the main reservoir-forming lithology in the case of dissolution, while the felsic granitoid is more likely to develop cracks. The formation of the disintegration belt is significantly linked to the presence of faulting. These belts were mostly induced by tectonic deformation along the Altyn fault belt from the late Oligocene to the early Miocene. The diversity in paleogeomorphology influences the extent of the weathering. The exhumation in the Altyn terrane from the late Jurassic to the Cenozoic corresponds to the weathering and hypergene leaching period of the weathering crust within granitoids. Three types of reservoirs are present in the rocks: fractured-porous (Type Ⅰ); porous (Type Ⅱ); and fractured (Type Ⅲ). The fractured-porous and fractured reservoirs were developed mainly in the granitic gneiss and granite, while the porous reservoir was formed in granitic diorite and granitic gneiss. The reservoirs that developed in the weathering crust of granitoids are dominated by Type Ⅰ and Type Ⅱ. The highest quality reservoir, which is the fractured-porous type, developed mainly in the dissolution belt of the weathering crust, and has a porosity ranging from 1.56% to 8.48% and a permeability ranging from 0.03 mD to 14.48 mD. The mechanisms of the development of weathering crust reservoirs provide further information for the hydrocarbon exploration of basement rocks worldwide.

Peer Reviewed Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables::12.2 - Per a 2030, assolir la gestió sostenible i l’ús eficient dels recursos naturals

Introduction Fe skarn deposits are the largest skarn deposits which are exploited for Fe as well as by-products of Cu, Co, Ni and Au (Meinert et al., 2005). They are one of the most important Fe deposits in the Zanjan province which have been exploited in recent years. The Alamkandi Fe deposit is one of these Fe skarn deposits which is located at 35 km west of the Mahneshan within the Takab-Takht-e-Soleyman subzone, northern Sanandaj- Sirjan zone. In this area, alternation of amphibolite, amphibole schist and biotite schist with intercalations of marble belonging to Paleozoic and intruded by late Oligocene alamkandi granitoid exist. This intrusion has caused contact metamorphism and formation of Fe mineralization. Some of the Fe skarn deposits in the Zanjan province were studied during the past years (i.e., Nabatian et al., 2017; Mokhtari et al., 2019) and valuable information is present about their geological and mineralization characteristics. However, the Alamkandi granitoid and Fe deposit have not been studied until the present. In this research study, geochemistry and petrogenesis of the Alamhandi granitoid along with mineralogy, textures and geochemistry of Fe deposit and thermodynamic conditions for formation of contact metamorphic rocks have been studied. Materials and methods This research can be divided into two parts including field and laboratory studies. Field studies include recognition of different parts of granitoid intrusion and skarn aureole along with sampling for laboratory studies. During field work, 65 samples were selected for petrographic and analytical studies. 19 thin sections and 13 polished thin sections were used for petrographical and mineralogical studies. For geochemical studies, 15 samples from granitoid and ore skarn sub-zone were analyzed by XRF and ICP-MS methods at the Zarazma laboratory, Tehran, Iran. Results Based on petrographic studies, the Alamkandi granitoid is composed of granodiorite, quartz diorite and porphyritic diorite. Granodiorites with hetrogranular texture are composed of plagioclase, quartz, K-feldspar, hornblende and biotite. Quartz diorites indicate porphyroid to seriate and hetrogranular textures and are composed of plagioclase, clinopyroxene, hornblende and quartz. Porphyritic diorites have porphyritic texture with plagioclase and amphiboles phenocrysts. The Alamkandi granitoids demonstrate calc-alkaline to high-K calc-alkaline affinity and can be classified as metaluminous I-type granitoids. Primitive mantle-normalized (McDonough and Sun, 1995) trace elements patterns for the Alamkandi granitoids indicate LILE and LREE enrichment along with negative HFSE anomalies and positive Pb anomaly. Chondrite-normalized (McDonough and Sun, 1995) REE patterns for these rocks demonstrate LREE enrichment (high LREE/HREE ratio). Based on tectonic setting discrimination diagrams, the Alamkandi granitoids were formed in the active continental margin. Fe mineralization in the Alamkandi area crops out in discrete places as massive and lens-shaped bodies. The Northern outcrop body has 150m length and up to 50m width, while the southern outcrop body has 100m length and up to 20m width. Microscopic studies reveal that the skarn zone at the Alamkandi granitoid is composed of garnet skarn, pyroxene skarn, epidote pyroxene skarn, serpentine skarn, and ore skarn sub-zones. Magnetite is the main ore mineral along with some pyrite and chalcopyrite. Garnet, clinopyroxene, olivine, serpentine, epidote, actinolite, calcite and quartz are present as gangue minerals. Based on the field and microscopic studies, the Alamkandi Fe deposit has massive, banded, disseminated, brecciated, vein-veinlets, replacement and relict textures. Based on mineralogical and textural studies, the skarnization processes in the Alamkandi deposit can be divided into 3 stages including: (1) isochemical metamorphic stage, (2) prograde metasomatic stage and (3) retrograde metasomatic stage. Discussion Based on skarn mineralogy, the XCO2 vs. T and T vs. logƒO2 diagrams were used to determine the possible physio-chemical conditions. According to these diagrams and considering mineralogical and textural evidence, maximum temperature for formation of olivine in XCO2≈0.1 and P=1kb was about 450-600°C. Furthermore, garnet and clinopyroxene were formed simultaneously at 430-550°C and ƒO2 equal 10-18 to 10-22. In temperatures less than 450°C, olivine was replaced by serpentine while in temperatures less than 430°C and increasing ƒO2, garnet and clinopyroxene were replaced by epidote + quartz + calcite and actinolite + quartz + calcite, respectively. In temperatures less than 430°C, fluids in equilibrium with granitic intrusion and with relatively high sulfidation (ƒS2>10-6), were not in equilibrium with andradite. Therefore, andradite was replaced with quartz + calcite + pyrite. With reducing ƒS2 (

Geothermal energy is a form of renewable energy with a long tradition in European countries, although it is scarcely used in Spain. One of the reasons for this is the poorly studied geothermal potential of the Spanish territory. In recent years, data published on terrestrial gamma radiation and the geochemistry of radioisotopes in rocks have suggested that the radiogenic heat production (RHP) in some areas of Spain is high. In this work, we assessed the RHP by analysing the U, Th, and K contents of the rocks underlying the most important campus of the University of A Coruña (northwest Spain), using in situ handheld gamma-ray spectrometry (GRS) and X-ray fluorescence spectrometry (XRF). Our results provide a good fit of the radioisotope contents and unexpectedly high RHP, compared with average data observed in similar rocks (granodiorite). These results reveal that GRS is a very reliable tool for studying the RHP of rock surfaces, and that geothermal energy can be used in the area (i.e., the studied campus, but also most of the city of A Coruña, as it is built on the same underlying rock) for central heating in buildings using ground-source heat pumps (GSHPs)., This research has been funded by the Consellería de Cultura, Educacion, e Ordenacion Universitaria, Xunta de Galicia, Spain (programmes ED431B 2018/47 and ED431B 2021/17).

The timing of the Lhasa–Qiangtang collision following the closure of the Bangong–Nujiang Tethys Ocean has not been well constrained. An integrated study of whole-rock geochemistry and zircon U–Pb–Hf isotopes was carried out for Early Cretaceous quartz diorite-porphyrites and granites from the Yilashan and Amdo areas, northern Tibet. LA–ICP–MS zircon U–Pb dating reveal that the Yilashan and Amdo granitoids were emplaced at ~121–110 Ma. These granitic rocks display selective enrichment of light rare earth elements, large ion lithophile elements (e.g., Rb, U) and Th, but depletion of Sr and high field strength elements (e.g., Nb, Ta, Ti) compared to its neighboring elements. These new data, combined with regional geological setting, show that these igneous rocks were formed under a geodynamic setting of the Lhasa and Qiangtang (–Amdo) collision with oceanic slab breakoff and asthenospheric upwelling. The BNTO had been closed at ~121–110 Ma in the study area. Yilashan-Amdo granitoids roughly yield high (87Sr/86Sr)i ratios and obvious negative εNd(t) and zircon εHf(t) values along with old Nd TDM and zircon Hf TDM2 ages. Together with their variable U–Pb ages, these features indicate a Precambrian “hidden” crustal source beneath the northern Lhasa and Amdo terranes. The YLSS S-type granophyres were derived from partial melting of Paleoproterozoic lower crustal metagraywackes, whereas the YLSZ quartz diorite–porphyrites and the Amdo I- and A-type granites were mainly derived from partial melting of Paleo–Mesoproterozoic lower crustal mafic rocks with a certain amount of addition of mantle-derived melts. Minor amounts of the materials originated from the Amdo orthogneisses may also be involved in the formation of the YLSZ quartz diorite–porphyrites and the Amdo I-type granites. In addition, the Yilashan ophiolite was intruded by the ~112–108 Ma granophyric and quartz diorite–porphyritic intrusions before its final emplacement into the surrounding strata.

Introduction The chemical composition of biotite in mineralization associated with granitoids and copper porphyry deposits is sensitive to several chemical and physical factors. It is also related tomagmatic and hydrothermal activities including water concentration, halogen and metal deposits, oxidation-sulfidation equilibrium, volatility (in melt-fluid-vapor equilibrium), elemental distribution relationships, and temperature and pressure of economic deposits (Webster, 1997, 2004). Material and methods Detailed field studies have been done, and several thin sections and polished thin sections were studied by conventional petrographic methods. Thirty points of biotite grains were selected and analyzed by a CAMECA SX Five electron probe micro-analyzer with 15 kV accelerator voltage and 20 nA beam current (5 μm beam size) at the Institute of Geology and Geophysics in the Chinese Academy of Sciences (IGG-CAS). The results were processed using MICA + software (Yavuz, 2003a, 2003b). Results and Discussion The Geysour granitoid pluton (Lower Cretaceous) consists of granodiorite, mafic microgranular enclaves, and micro-granite sill. The granodioriticrocks are mainly composed of plagioclase, quartz, K-feldspar and biotite along with accessory minerals of zircon, apatite and magnetite. Mafic microgranular enclaves are composed of quartz diorite, granodiorite and biotite granite, with fine-grained to porphyry texture and large eyes of quartz and plagioclase assemblages. The microgranite has porphyry texture with a fine-grained groundmass. Its phenocrysts are plagioclase, quartz and biotite along with accessory minerals of allanite, needle like apatite, epidote and calcite. Biotite is the only ferromagnesian mineral in theGeysour granitoid which falls into the category of real trioctahedral mica. The biotites of granodiorite and enclave samples are in group I and group of ferrous biotites. The biotitesof microgranite samples are in group I and group of magnesium biotites (Tischendorf et al., 1997). In the 10*TiO2-(FeOtot+MnO)-MgO ternary diagram (Nachit et al., 2005) all the analyzed biotites fall into the field of reequilibrated primary biotite. The formation temperatures of biotites in granodiorite, enclave and microgranite are 653-732 oC, 631-724 oC and 689-732 oC, respectively (Luhar et al., 1984; Henry et al., 2005). The mean pressure values are about 4 Kbar ​​for granodiorite and enclave and 2 Kbar for microgranite (Uchida et al., 2007). Biotites of granodioriteand enclave biotites are located on top of the NNO buffer, which correspond to biotite compositions of magnetite series magmas, and biotites ofmicrogranite lie below the NNO buffer line and within the QFM buffer range. Biotite composition based discriminant diagrams cannot be used to determine the tectonic setting of the Geysour granitoids because they are low temperature I-type granites. The mean logarithmic ratios of fH2O to fHF and fHCl, and fHF to fHCl for the rocks studied are as follows: log(fH2O/fHF)fluid=4.56, log(fH2O/fHCl)fluid=4.47 and log(fHF/fHCl)fluid=-0.53. The first two values ​​are much larger than 1 indicating that the fluids are rich in water. Also, all biotites have high angles with linear trends of log(fHF/fHCl), log(fH2O/fHCl) and log(fH2O/fHF) indicating changes in fugacity conditions and halogen content of the fluid due to wall-rock reaction (Boomeri et al., 2009). Hydrothermal fluid fugacity ratio has been calculated for biotites of granodiorite, enclaves and microgranite samples at mean temperature of 661 oC, 654 oC and 703 o C, respectively, which indicate that hydrothermal fluids are of potassic type, because the log(fH2O/fHCl) is high, the log(fHF/fHCl) is slightly negative and the log(fH2O/fHF) is lower than that of phyllic alteration (Selby and Nesbitt, 2000). Meanwhile the magmatic fluid is significantly different from porphyry-type fluids (Baldwin and Pearce, 1982; Mason and Feiss, 1979; Selby and Nesbitt, 2000). References Baldwin, J.‌A. and Pearce, J.‌A., 1982. Discrimination of productive and nonproductive porphyritic intrusions in the Chilean Andes. Economic Geology, 77‌(3): 664–674. http://dx.doi.org/10.2113/gsecongeo.77.3.664 Boomeri, M., Nakashima, K. and Lentz, D.‌R., 2009. The Miduk porphyry Cu deposit, Kerman, Iran: A geochemical analysis of the potassic zone including halogen element systematics related to Cu mineralization processes. Journal of Geochemical Exploration, 103‌(1): 17–29. https://doi.org/10.1016/j.gexplo.2009.05.003 Henry, D.‌J., Guidotti, C.‌V. and Thomson, J.‌A., 2005. The Ti-saturation surface for low-to-medium pressure metapelitic biotites: Implications for geothermometry and Ti-substitution mechanisms. American Mineralogist, 90‌(2–3): 316–328. https://doi.org/10.2138/am.2005.1498 Luhar, J.‌F., Carmichael, I.‌S.‌E. and Varekamp, J.‌C., 1984. The 1982 Eruptions of El Chichon volcano, Chiapas, Mexico: Mineralogy and Petrology of the anhydrite-bearing Pumices. Journal of volcanology and geothermal research, 23 (1–2): 69–108. https://doi.org/10.1016/0377-0273(84)90057-XMason, D.‌R. and Feiss, P.G., 1979. On the relationship between whole rock chemistry and porphyry copper mineralization. Economic Geology, 74(6): 1506–1510. https://doi.org/10.2113/gsecongeo.74.6.1506 Nachit, H., Ibhi, A., Abia, El.-H. and Ohoud, M.B., 2005. Discrimination between primary magmatic biotites, reequilibrated biotites and neoformed biotites. Comptes Rendus Geoscience, 337‌(16): 1415–1420. https://doi.org/10.1016/j.crte.2005.09.002 Selby, D. and Nesbitt, B.E., 2000. Chemical composition of biotite from the Casino Porphyry Cu-Au-Mo mineralization, Yukon, Canada: Evaluation of magmatic and hydrothermal fluid chemistry. Chemical Geology, 171‌(1–2): 77–93. https://doi.org/10.1016/S0009-2541(00)00248-5 Tischendorf, G., Gottesmann, B.‌F. Orster, H.J. and Trumbull, R.B., 1997. On Li-bearing micas: estimating Li from electron microprobe analyses and improved diagram for graphical representation. Mineralogical Magazine, 61‌(409): 809–834. https://doi.org/10.1180/minmag.1997.061.409.05 Uchida, E., Endo, S. and Makino, M., 2007. Relationship between solidification depth of granitic rocks and formation of hydrothermal ore deposits. Resource Geology, 57(1): 47–56. https://doi.org/10.1111/j.1751-3928.2006.00004.x Webster, J.D., 1997. Exsolution of magmatic volatile phases from Cl-enriched mineralizing granitic magmas and implications for oremetal transport. Geochimica et Cosmochimica Acta, 61‌(5): 1017–1029. https://doi.org/10.1016/S0016-7037(96)00395-X Webster, J.D., 2004. The exsolution of magmatic hydrosaline chloride liquids. Chemical Geology, 210‌(1–4): 33–48. https://doi.org/10.1016/j.chemgeo.2004.06.003 Yavuz, F., 2003a. Evaluating micas in petrologic and metallogenic aspect: I—definitions and structure of the computer program Mica+. Computational Geosciences, 29‌(10): 1203–1213. https://doi.org/10.1016/S0098-3004(03)00142-0 Yavuz, F., 2003b. Evaluating micas in petrologic and metallogenic aspect: Part II—Applications using the computer program Mica+. Computational Geosciences, 29‌(10): 1215–1228. https://doi.org/10.1016/S0098-3004(03)00143-2

Introduction The Iranian plateau is part of the Alpine-Himalayan orogenic belt, which consists of several continental fragments separated from each other by major boundary faults and/or ophiolitic suture zones (Gansser, 1981). Generally, the tectonic evolution of Iran has been controlled by the opening and closure of the Proto-Tethys, Paleo-Tethys and the Neo-Tethys during the Precambrian-Cambrian, Paleozoic and Cenozoic, respectively. The study area is located in the northwest of Iran (the Kurdistan province) and 20 km northeast of the city of Saqez. This area is a part of the northern Sanandaj-Sirjan Zone (Aghanabati, 2005). This belt is response to opening and subduction of Neo-Tethyan oceanic crust beneath the Central Iran (Alavi, 1994). During Cretaceous-Tertiary eras, numerous granitoid bodies were formed in this belt. The Saheb granitoid is one of these granitoid bodies which mainly consists of monzogranite, quartz monzonite and quartz monzodiorite. The aim of this research study is to discuss the evolution of the Late Cretaceous-Early Paleocene Saheb granitoids in the Sanandaj-Sirjan zone based on geology, petrography and geochronology results. Material and methods In this study, 70 rock samples were collected from different types of intrusive rocks from which 30 thin sections were prepared for petrographic studies. Furthermore, four samples from the granitoid bodies (quartz monzonite, quartz monzodiorite and monzogranite) were selected for U-Pb dating. Approximately 100 to 150 zircon grains were hand-picked by a binocular microscope from each sample. Cathodo-luminescence imaging and dating of zircon grains were examined at the China University Geosciences (Wuhan branch). Geochronological analysis were performed by using the (LA)-ICP-MS method at the China University Geosciences (Wuhan branch). The detailed analytical method is presented in Liu et al. (2010a, 2010b). Geology of the study area The Saheb granitoid body is located in the Sanandaj-Sirjan zone. According to the geological map of Chapan (scale: 1/100000, Kholghi khosraghi, 1999), the Precambrian to Quaternary units are exposed in the study area. The oldest units are the Kahar, Bayandor and Soltanieh Formations with Precambrian to Cambrian age. The Permian sediments, the Ruteh and Doroud Formations, include sandstone, shale and carbonate. The Jurassic units are found in the northwest of the region, and include sandstones and shale. The Cretaceous sedimentary units are located in the south of the study area. These sediments contain sandstone, limestone, silty-limestone, shale and dolomitic limestone. During Late Cretaceous-Early Paleocene era the Saheb granitoid intruded within the oldest units and caused Fe skarn type deposits in the Saheb area. The Saheb granitoid have been cut by a series of diabasic dikes. Results The Saheb granitoid consists of several intrusive bodies containing quartz monzonite, quartz monzodiorite and monzogranite. The major minerals in the quartz monzodiorite consist of plagioclase (35- 40%), quartz (15- 20%), orthoclase (20- 25%), and mafic minerals such as biotite and amphibole (10-15%) with granular texture. The quartz monzonitic rocks show granular and poikilitic textures. Plagioclase (25- 35%), quartz, orthoclase (30- 40%), biotite and amphibole (10-15%) are the main important minerals in the quartz monzonite. Plagioclase (20-25%), quartz (20-30%), orthoclase (30-40%), biotite and amphibole (15%) are the major minerals in the monzogranite. Zoning in zircon crystals from all four samples is well developed representing their magmatic origin (Hancar and Miller, 1993). Measurements of U-Pb in the Saheb granitoid zircon grains of quartz monzonite samples show their ages to be 62.03±0.56 Ma and 58.9±0.9 Ma. The age of monzogranite is 67.9±1.3 Ma and the age of quartz monzodiorite is 61.1±0.56 Ma. Generally, the age of this granitoid body indicates that the Saheb granitoid has occurred during the Cretaceous- Paleocene time. Discussion Based on field and microscopic studies, the Saheb granitoid bodies have been divided into three types of quartz-monzonite, quartz-monzodiorite and monzogranite. The field and mineralogical studies suggest that the Saheb granitoid is an I-type granitoid. The mineralogical variations in this granitoid suggest that the fractional crystallization has played an important role in differentiation of different compositional phases in the Saheb granitoid. According to the geochronological results, during Late Cretaceous to Early Paleocene, the Saheb granitoid intruded within the Permian and Cretaceous units in the magmatic-metamorphic Sanandaj-Sirjan zone. These granitoids were formed by subduction of Neo-Tethys Ocean beneath the Iranian plateau. It should be mentioned that the intrusion of these granitoids into the Permian carbonates and Cretaceous carbonate and shale caused formation of skarn type iron oxide mineralization. Acknowledgements The authors are grateful to the authorities at the University of Zanjan for their financial support. We also thank the authorities at the China University Geosciences (Wuhan branch) for their financial support to perform U-Pb zircon analysis.

Introduction Fe skarn deposits are one of the important Fe deposits in the Zanjan province which have been exploited in recent years. The Qozlou Fe deposit is one of these Fe skarn deposits which is located at 65 km west of Zanjan. In this area, alternation of micro-sparitic limestone, marly limestone, shale and sandstones of Upper Cretaceous were intruded by Late Eocene granitoids. This event caused to metamorphism contact and it caused the formation of Fe mineralization. Some of the Fe skarn deposits in the Zanjan province were studied during the past few years (e.g. Nabatian et al., 2017) and valuable information is present about their geological and mineralization characteristics. However, Qozlou granitoid and Fe deposit have not been studied yet. In this research, petrology and geochemistry of the Qozlou granitoid along with petrographic characteristics, mineralogy, structure and texture of Fe deposit and thermodynamic conditions for formation of contact metamorphic rocks have been studied. Materials and methods This research study can be divided into two parts including field and laboratory studies. Field studies include The recognition of different parts of granitoid intrusion and skarn aureole along with sampling for laboratory studies. Thus, 50 samples were selected for petrographic and analytical studies. 16 thin sections and 16 thin-polish sections were used for petrographical and mineralogical studies. 13 samples from granitoid and ore skarn sub-zone were analyzed by XRF and ICP-MS methods at the Zarazma laboratory, Tehran for geochemical studies. Results Based on petrographic studies, the Qozlou granitoid is composed of porphyritic granite-granodiorite and quartz monzodiorite. Porphyritic granite-granodiorite have porphyritic to porphyroidic, micro-graphic and felsophyric textures and are composed of plagioclase, quartz, K-feldspar, hornblende and biotite phenocrysts within quartz-feldspatic groundmass. Quartz monzodiorites indicate porphyroidic texture and they are composed of plagioclase, hornblende, quartz and K-feldspar. The Qozlou granitoid demonstartes high-K calc-alkaline affinity and it is classified as metaluminous I-type granitoids. Trace elements normalized by primitive mantle (Sun and McDonough, 1989) for Qozlou granitoid indicate LILE and LREE enrichment along with negative HFSE anomalies and distinctive positive Pb anomaly. Chondrite-normalized (Nakamura, 1974) REE patterns for the Qozlou granitoid demonstrate LREE enrichment (high LREE/HREE ratio). Based on tectonic setting discrimination diagrams, the Qozlou granitoid were formed in active continental margin. Microscopic studies reveal that the skarn zone in Qozlou is composed of garnet skarn, garnet-pyroxene skarn, pyroxene skarn, epidote skarn, and pyroxene-bearing marble sub-zones. The Ore zone is present as massive and lens-shaped with 300m length and up to 30m width. Magnetite is the main ore mineral along with some pyrite, chalcopyrite and pyrrhotite. Garnet, clinopyroxene, epidote, actinolite, calcite and quartz present in skarn zone. Based on field and microscopic studies, the Qozlou Fe deposit indicates massive, banded, disseminated, brecciated, vein-veinlets, replacement and relict textures. Based on mineralogical and textural studies, skarnization processes in the Qozlou deposit can be divided into 3 stages including: (1) isocheimal metamorphic stage, (2) prograde metasomatic stage and (3) retrograde metasomatic stage. Chondrite-normalized (Sun and McDonough, 1989) REE and trace element patterns for different skarn samples and porphyritic granite demonstrate similar patterns. Discussion Since all of minerals present in the Qozlou skarn aureole are located in Ca-Fe-Si-C-O-H system, we used the temperature vs. logƒO2 diagram (Einaudi, 1982) to determine possible physico-chemical conditions for skarn formation in the Qozlou. Based on this diagram and considering mineralogical and textural evidence, garnet and clinopyroxene were formed simultaneously in 430-550°C and ƒO2 equal 10-23 to 10-26. In the temperature less than 430°C and increasing ƒO2, garnet and clinopyroxene replaced by epidote, actinolite, quartz and calcite, respectively. Furthermore, in temperature of less than 430°C, fluids in equilibrium with granitic intrusion and with relatively high sulfidation (ƒS2>10-6), were not in equilibrium with andradite. Therefore, andradite was replaced by quartz, calcite and pyrite. With reducing ƒS2 (

Purpose of this study is to prove most probable existence of economical U-Th mineralisations within Tatvan Basin which have been hidden among foreign international research project manuscripts of Lake Van and to inform the importance of national exploration studies. Lake Van is a pull-apart basin formed within Quaternary Muş-Zagros suture zone with right lateral movement. Calculations on heat transfer below the Tatvan Basin indicate that a constant heat flow is about fourty times the continental average which have been only reported from some oceanic ridges. Data indicate the heat source below Tatvan Basin bottom represents a steadily collapsing cauldron subsidence of Nemrut volcano’s magma chamber. Lake Van surface water has mean 76ppb dissolved uranium content of hyrothermal and authigenic origin. It is calculated that there is at least 50.000 tons of dissolved uranium exists in the Lake Van waters. Ultimate deposition of U-Th mineralisation within euxinic Tatvan Basin have been expected to be a continuous process during geologic history of Lake Van as long as uranium resources remain and its NaHCO3 water functions as dissolving agent Sodic Lake Van waters continuously dissolve uranium from 1) high 3He/4He and U-Th containing hydrothermal fluxes of mantle origin coming up through cauldron subsidence faults of Tatvan Basin, 2) per-alkaline rhyolitic volcanic ash rain of Nemrut volcanism, 3) Bitlis granitoid Massive basement, 4) repeated authigenic disentegrations of U to (Th and 4He) within the sedimentary deposites of Tatvan Basin through its 600.000 years history. Tatvan Basin is the deepest basin with 450m depth, 300km2 flat area and constant unoxic basal water table undisturbed by currents and has the following verifications for Quaternary U-Th depositions in the unconsolidated porous sediments: 1) organic mass rich levels with reducing microbial activities, 2) evaporitic dolomites deposited during low stand lake levels with high U-Th concentrations, 3) varved, mixed-layered clays with high hectorite content, 4) sub-aquaeous, basic-intermediate volcanic basement intrusions with reducing properties, 5) measured very low redox potentials in basal environment, 6) very high density of U-Th. Drilling core sequence and the gamma ray logs from Ahlat Ridge have been used in the foreign literature published since 1974 until now while the existence or non-existence of uranium has not been mentioned. Gamma ray logs of drilling cores and their pore water analyses from Tatvan Basin were carried out abroad but not published yet. Thus gamma ray logs belonging only to shallow Ahlat Ridge sequence where uranium mineral precipitation is not possible is misleading.

Pluton Gornjana pripada variscijskom magmatskom pojasu Karpato-Balkanida istočne Srbije. Petrološka i geohemijska ispitivanja prikazana u ovoj studiji su pokazala da je pluton izgrađen od: kvarcdiorita i kvarcmonconita koji se uglavnom pojavljuju kao anklave (grupa 1) i granodiorita i sijenogranita koji se sreću kao nepravilna magmatska tela (grupa 2), uz lamprofire koji su alterisani (zbog čega su korišćeni literaturni podaci o svežijim lamprofirima). Stene grupa 1 i 2 pokazuju hipidiomorfno-zrnastu strukturu i masivnu ili kumulatnu teksturu. Pored varijabilne količine kvarca, plagioklasa i ortoklasa, sadrže i biotit i/ili amfibol, kao i seriju akcesorija: sfen, apatit, alanit, cirkon, epidot i metalične minerale. Na svim Harkerovim dijagramima uočava se trend od najprimitivnijih lamprofira, preko stena grupe 1, sve do najizvedenijih stena grupe 2. Takođe se vidi da varijacije sadržaja TiO2, Fe2O3, CaO, MgO i P2O5 prema sadržaju SiO2 i sadržaja Cr prema koncentraciji vanadijuma grade uglavnom komaptibilne linearne trendove idući od lamprofira ka grpi 2. Al2O3 i Na2O pokazuju najpre nekompatibilni, a onda kompatibilni trend. Nekompatibilni elemenenti (Th, U, Zr, Y i Nb) pokazuju rasipanje podataka. Svi ovi pokazatelji upućuju na petrogenetsku povezanost stena - Ti oksidi i apatit, uz plagioklas koji je najverovatnije značajnije frakcionisan tek kada se rastop približio sastavu od oko ~64 wt% SiO2. Međutim, prisustvo mafičnih anklava, kao i promena 87Sr/86Sri (od 0.7049 u najizvedenijoj probi do 0.7074 u najprimitivnijoj probi) ukazuju da se i proces mešanja magmi, uz frakcionaciju, odvijao u toku geneze ispitivanog plutona. Pojednostavljeni geohemijski model promene sadržaja Nb prema V od najprimitivnijeg lamprofira 2B do najizvedenije probe TN-6 u toku procesa mešanja magmi i kristalizacije grubo ilustruje evoluciju geneze ispitivanog plutona. Druga dva modela koji pokazuju promene sadržaja V prema variranju Zr/Nb odnosa i prema variranju 87Sr/86Sri svedoče da su procesi geneze granitoida Gornjana bili složeniji i da su različite porcije lamprofirskih magmi učestvovale u mešanju magmi, dajući najizvedenije kisele članove. Karakter primarnih rastopa koji su učestvovali u mešanju nije moguće precizno utvrditi na osnovu trenutnih rezultata. Može se, međutim, pretpostaviti da je krajnji kiseli član najverovatnije kalko-alkalna magma kiselog/intermedijarnog karaktera (granodiorit) koja odgovara I-tipu magme, dok je najprimitivnija magma koja je učestvovala u procesu hibridizacije lamprofirskog (kalijsko/ultrakalijskog) karaktera

Zajkan area as a part of Tarom-Hashjin magmatic belt contains some granitic intrusions which are intruded into the Eocene volcano-sedimentary rocks. Eocene volcano-sedimentary rocks include alternation of acidic to intermediate tuffs and lavas. Petrographical studies demonstrate that these intrusions composed of gabbro, pyroxene quartz monzodiorite, pyroxene quartz monzonite and granodiorite. These intrusions have high-K calc-alkaline nature and classified as I-type metaluminous granitoids. Based on the spider diagrams, these intrusions have similar patterns which are indicative for their genetic relation. These diagrams indicate enriched LILEs along with negative anomalies of HFSEs. Chondrite-normalized REE patterns demonstrate LREE enrichment with high ratio of LREE/HREE and (La/Yb)N ratio between 6.1-9.1. Based on field investigation, petrological and geochemical studies, and tectonic setting discrimination diagrams, it seems that Zajkan intrusions were formed from a subduction related metasomatized lithospheric mantle in a post-collisional setting.

Introduction The formation of the Zagros orogenic belt is attributed to northeastward oblique subduction of the Neotethys beneath the western border of central Iran. This was followed by continental collision between the Afro-Arabian plate and the central Iran microcontinet (Zarasvandi et al., 2015). The Zagros orogen is characterized by three main parallel structural zones consisting of Zagros fold and thrust belt, the Sanandaj–Sirjan metamorphic zone, and the Urumieh–Dokhtar magmatic arc (Mohajjel et al., 2003). The Urumieh–Dokhtar magmatic arc is dominated by the widespread occurrence of Eocene to Quaternary intrusive and extrusive rocks. It is considered as being one of the main Cu bearing regions in the world, where world class giant porphyry deposits, as well as large and small sub-economic porphyry Cu ± Mo ± Au systems have been reported and investigated by many authors (Shafiei et al., 2009; Zarasvandi et al., 2005). In addition to UDMA, the Sanandaj-Sirjan zone (SSZ) hosts several Jurassic-Cretaceous intrusive complexes extending from the northwest to southeast SSZ. It should be noted that these granitoids are barren and porphyry mineralization has not been accompanied with these intrusions. This paper tried to compare the available geochemical data of productive granitoids in the Urumieh-Dokhtar (i.e., Dalli, Ali-Abad and Darreh-Zerreshk, Parkam, Sarcheshmeh, Meiduk and Sungun), and those of barren intrusions in the Sanandaj-Sirjan zone (i.e., Aligodarz, Bourujerd, Alvand, Astaneh, Hasan Robat, and Siah Koh). Materials and methods This investigation is based on the available geochemical data on the six barren intrusions in the SSZ (i.e., Aligodarz, Bourujerd, Alvand, Astaneh, Hasan Robat and Siah Kohe), and productive intrusive rocks (porphyry associated intrusions) in the UDMA (i.e., Dalli, Ali-Abad and Darreh-Zerreshk, Parkam, Sarcheshmeh, Meiduk and Sungun). Data for the UDMA porphyry intrusions (41 samples) were adopted from studies of Daneshjou (2014), Zarasvandi et al. (2005), Taghipour and Mohammadi Laghab (2014), Barzegar (2007), Taghipour (2007), and Hezarkhani (2006). Furthermore, the data of the SSZ barren intrusions (42 samples) comes from Esna Ashari et al. (2012), Khalaji et al. (2007), Aliani et al. (2012), Tahmasbi et al. (2010), Alirezaei and Hassanzadeh (2001), and Arvin et al. (2007). Two criteria were used for selection of 83 representative samples: (1) samples with a relatively similar mineralogical and compositional range (quartz diorite, quartz monzonite, granodiorite and granite), and (2) samples with the least amount of alteration (minimal amounts of Loss On Ignition; LOI wt.% = H2O + CO2). Results Productive intrusions in UDMA have positive Eu anomalies, LREE enrichment relative to HREE, and high Lan/Ybn ،Sr/Y، Dyn/Ybn، Lan/Smn ratios. In comparison, barren granitoids in the SSZ are characterized by steep downward LREE to HREE, negative Eu anomalies and low Lan/Ybn ، Sr/Y، Dyn/Ybn، Lan/Smn ratios. Discussion Based on the presented results, it is proved that due to the lack of considerable crustal thickness in SSZ (during the subduction of the Neotethyan oceanic lithosphere under the SSZ zone), and the presence of dry magma (low H2O contents), the SSZ granitoids exhibit barren characteristics. In contrast, during the ongoing processes of closure of Neo-Tethys and during compression and crustal shortening, magma mixing and evolution toward high magmatic water content lead to the increasing of metal endowment in the porphyry associated granitoids of (UDMA) It seems that magma generation from the melting of thickened lower crust (garnet amphibolite source) could be considered as one important key factors for the generation of metal-rich magmas with high oxidation state and high H2O contents has led to the development of porphyry Cu systems in the UDMA compared to those of SSZ granitoids. Acknowledgements The authors are grateful to the Shahid Chamran University of Ahvaz for the research funding by the Grant Commission in 2017. References Aliani, F., Maanijou, M., Sabouri, Z. and Sepahi, A.A., 2012. Petrology, geochemistry and geotectonic environment of the Alvand Intrusive Complex, Hamedan, Iran. Chemie der Erde-Geochemistry, 72(4): 363–383. Alirezaei, S. and Hassanzadeh, J., 2012. Geochemistry and zircon geochronology of the Permian A-type Hasanrobat granite, Sanandaj–Sirjan belt: A new record of the Gondwana break-up in Iran. Lithos, 15(151): 122–134. Arvin, M., Pan, Y.M., Dargahi, S., Malekizadeh, A. and Babaei, A., 2007. Petrochemistry of the Siah-Kuh granitoid stock southwest of Kerman, Iran: implications for initiation of neotethys subduction. Journal of Asian Earth Sciences, 30(3): 474–489. Barzegar, H., 2007. Geology, petrology and geochemical characteristics of alteration zones within the Seridune prospect, Kerman, Iran. Ph.D. thesis, Aachen University, Aachen, Germany, 320 pp. Daneshjou, M., 2014. Investigation of geology, geochemistry and genetic model of the Dalli porphyry Cu–Au deposit, Delijan, Markazi province. M.Sc. Thesis, Shahid Chamran University, Ahvaz, Iran, 150 pp. (in Persian with English abstract) Esna-Ashari, A., Tiepolo, M., Valizadeh, M.V., Hassanzadeh, J. and Sepahi, A.A., 2012. Geochemistry and zircon U–Pb geochronology of Aligoodarz granitoid complex, Sanandaj-Sirjan zone, Iran. Journal of Asian Earth Sciences, 43(1): 11–22. Hezarkhani, A., 2006. Petrology of the intrusive rocks within the Sungun porphyry copper deposit, Azerbaijan, Iran. Journal of Asian Earth Sciences, 27(3): 326–340. Khalaji, A.A., Esmaeily, D., Valizadeh, M.V. and Rahimpour-Bonab, H., 2007. Petrology and geochemistry of the granitoid complex of Boroujerd, Sanandaj-Sirjan Zone, Western Iran. Journal of Asian Earth Sciences, 29(5): 859–877. Mohajjel, M., Fergusson, C.L. and Sahandi, M.R., 2003. Cretaceous–Tertiary convergence and continental collision, Sanandaj–Sirjan zone, western Iran. Journal of Asian Earth Sciences, 21(4): 397–412. Shafiei, B., Haschke, M. and Shahabpour, J., 2009. Recycling of orogenic arc crust triggers porphyry Cu mineralization in Kerman Cenozoic arc rocks, southeastern Iran. Mineralium Deposita, 44(3): 265–283. Taghipour, N., 2007. The application of fluid inclusions and isotope geochemistry as guides for exploration, alteration and mineralization at the Meiduk porphyry copper deposit, Shahr-Babak, Kerman. Unpublished Ph.D. thesis, Shahid Bahonar University, Kerman, Iran, 321 pp. Taghipour, N. and Mohammadi Laghab, H., 2014. Sara (Parkam) Porphyry Copper Deposit in Kerman, Iran: Petrography, Geochemistry and Geodynamic Setting. Geochemistry Journal, 1(3): 14–26. Tahmasbi, Z., Castro, A., Khalili, M., Khalaji, A.A. and de la Rosa, J., 2010. Petrologic and geochemical constraints on the origin of Astaneh pluton, Zagros orogenic belt, Iran. Journal of Asian Earth Sciences, 39(3): 81–96. Zarasvandi, A., Liaghat, S. and Zentilli, M., 2005. Geology of the Darreh-Zerreshk and Ali-Abad porphyry copper deposits, central Iran. International Geology Review, 47(6): 620–646.

Grothite – rare F-Al-rich type of titanite – has been found in accessory zircon from the granitoids of the pre-Jurassic basement of the Verkhnerechensky oil-gas area (in the southern part of the Yamal Peninsula) as a result of the study. Titanite forms rare inclusions (so-called minerals-prisoners) in the central parts of zircon crystals; in our sample of 35 individuals only two grains of titanite have been discovered. The measurement of the chemical composition of the mineral has been carried out on an electron-probe microanalyzer CAMECA SX 100, equipped with five wave spectrometers (IGG UrB RAS, Ekaterinburg). According to the microprobe analysis, the mineral has an unusual chemical composition, it shows the presence of significant concentrations of alumina (Al2O3 to 8.5 wt.%), rare earths elements (REE to 4.3 wt.%), and fluorine (F to 2 wt.%). This grothite is dramatically different in chemical composition from the accessory titanite of the matrix granitoid (monzoleicogranite), which is characterized by values close to the reference sphene. Overall, grothite is an intermediate connection between the two extreme members CaTiSiO4O (titanite) – CaAlSiO4F (synthesized Al-F-titanite), and the Verkhnerechensky mineral content of a hypothetical Al-F-titanite achieves a high level of 24–26 %. Unfortunately, grothite is crystallized in a wide range of temperatures and pressures which does not allow its use in thermodynamic reconstructions. The existence of grothite (or Al-F-titanite) is apparently determined not so much on the PT-conditions of rocks' formation, but most likely on the chemistry of the environment. So it is obvious that the Verkhnerechensky titanite was formed in the melt with an increased concentration of fluorine. It is the first record of grothite in the form of inclusions in accessory zircon.

Bangka Island is one of the islands in Indonesia which is traversed by Southeast Asia granitoid belt. This belt stretches from Burma (Myanmar) to Bangka Belitung. This granitoid has potential as a source rock of mineral that carrying tin and rare earth element. At present, mapping of granitoid rocks to the waters area is rarely published, so acoustic basement mapping is necessary to do in order to determine the distribution of granitoids in Toboali waters. The research method used is a single channel seismic with an energy source of 300 joules. The sound source uses a single plate boomer, so it has a high enough resolution but the penetration is not deep enough. Acoustic basement in Toboali waters varies in depth from 15 - 75 ms or getting deeper south. When viewed from the continuity of the acoustic basement, it is estimated that the granitoid is 7 km from the nearest coastline. Key words: single channel seismic, seismic interprtation, granitoid distribution, Toboali Waters, Bangka Belitung Province Pulau Bangka merupakan salah satu pulau di Indonesia yang dilalui oleh jalur granitoid Asia Tenggara. Jalur ini membentang dari Burma (Myanmar) hingga Bangka Belitung. Granitoid ini memiliki potensi sebagai batuan sumber pembawa mineral timah dan unsur tanah jarang. Pada saat ini pemetaan batuan granitoid pada daerah perairan jarang dipublikasikan, sehingga pemetaan batuan dasar akustik perlu dilakukan dalam rangka mengetahui sebaran granitoid di Perairan Toboali. Metode penelitian yang digunakan yaitu seismik single channel dengan sumber energi yang dikeluarkan sebesar 300 joule. Sumber suaranya menggunakan boomer single plate, sehingga memiliki resolusi yang cukup tinggi akan tetapi penetrasinya tidak cukup dalam. Batuan dasar akustik di Perairan Toboali memiliki kedalaman bervariasi mulai dari 15 – 75 ms atau semakin ke selatan semakin dalam. Jika dilihat dari kemenerusan batuan dasar akustiknya diperkirakan granitoid tersebut berada 7 km dari garis pantai terdekat. Kata kunci: Seismik single channel, interpretasi seismik, distribusi granitoid, Perairan Toboali, Provinsi Bangka Belitung

The Sarmeshk granitoid pluton is located in southeast of the Urumieh-Dokhtar magmatic zone in the Kerman province. Based on petrographic studies, the granitoid consist of three rock type of diorite, granodiorite and monzogranite. They are mainly composed of plagioclase, alkali-feldspar, quartz, amphibole and biotite. Mineral chemistry of diorite, granodiorite and monzogranite indicate that the feldspars are orthoclase and oligoclase-andesin in composition. The calcic amphiboles have magnesiohornblende composition that is feature of I-type granite. The biotites with Fe/ (Fe+Mg)>0.33 are magnesio-biotites. The amounts of Al2O3, TiO2 and Mg# in amphiboles indicate crust and mantle mixing in the formation of Sarmeshk granitoid magma. Thermobarometer studies indicate that the pressure of hornblende crystallization in the Sarmeshk intrusion is about 1 to 2 Kbar and have been formed in the depth of 5.8 km. The thermometer of the hornblende- plagioclase reveal temperatures of 650-750 °C for the intrusion. The composition of hornblendes suggests their formation in high oxygen fugacity condition, which is in accordance with their mineralogical characteristics and active continental margin tectonic setting of Sarmeshk granitoid pluton.

The Oligo-Miocene Qazan granitoid body caused contact metamorphic of surrounding rocks and skarn formation in the wall limestone. The main intrusive rocks are essentially granite to diorite in composition. Two different types of skarn, exo and endoskarn have been developed. On the base of microprobe data, the northern skarn are characterized by zoning and the amounts of andradite and grossular changes oscillatory. While garnets from the southwestern skarn is predominantly andradite in composition. Using Fe/Ti vs. Al/ (Al+Fe+Mn) diagram that were calculated based on the mole percent of the used elements, it is estimated that about less than 50 percent hydrothermal waters were involved for the northern skarn whereas it was over this amount for the southwestern skarn. This leds to difference in garnet composition. The composition of clinopyroxene in both skarns is the same (diopside). As a result, hydrothermal fluids have not had much influence on pyroxene genesis. With regards to the occurrence of mineral assemblage and the presence of wollastonite in the skarns under study, these rocks have evolved in temperature above 500 ° C and O2 fugacity in the range of 10-17 to 10-15.

Khanchay-Aliabad area as a part of Tarom magmatic belt contains some shallow depth intrusions which are intruded the Eocene volcanic- sedimentary rocks and have very close association with Cu mineralization. The Eocene volcanic- sedimentary rocks include alternation of basalt, basaltic andesite and andesite, various kinds of tuff, tuffaceous sandstone, sandstone, siltstone and occasionally shale. Petrographical studies demonstrate that intrusions are pyroxene quartz monzonite and olivine gabbro in composition. The Khanchay pyroxene quartz monzonite have porphyritic to porphyroidic, hetero-granular to sereitic, ophitic and sub- ophitic textures and composed of plagioclase, clinopyroxene, hornblende, quartz, K-feldspar and biotite. The Aliabad pyroxene quartz monzonite shows porphyritic to porphyroidic textures composing of plagioclase, clinopyroxene and hornblende in the quartz- feldspatic matrix. The Khanchay olivine gabbro is characterized by the presence of coarse grained granular, ophitic and sub- ophitic textures as well as the occurrence of plagioclase, clinopyroxene and olivine. Geochemical studies indicate that the Khanchay- Aliabad pyroxene quartz monzonitic intrusions have SiO2 content varying from 59.58 to 61.34 %. These intrusions have high- K calc- alkaline nature and are classified as I-type metaluminous granitoids. Their similar patterns on spider diagrams are indication of genetic relation of these intrusions. On these diagrams LILEs (Ba, K, Th and Pb) enrichment along with negative anomalies of HFSEs (Nb and Ti) are observed. Moreover, the Chondrite normalized REE patterns demonstrate LREE enrichment with high ratio of LREE/HREE and Lan/Ybn ratio ranging from 3.08 to 3.72. The overall field investigation, petrological and geochemical studies as well as tectonic setting discrimination diagrams confirm that the Khanchay- Aliabad high-K intrusions were formed from a subduction related metasomatized lithospheric mantle in a post- collisional setting.

On the base of petrology, the Mirabad- Chehel Khane granitoid, east of Bouin-Miandasht, dominantly consists of syenogranite, monzogranite, alkali granite and granodiorites. The main minerals of these rocks are quartz, alkali feldspar (Orthoclase), plagioclase (Albite - Oligoclase), biotite, ± amphibole with minor amount of allanite, zircon, titanite, apatite, ± tourmaline. The biotite from the granites are Fe-rich type (annite) and primary magmatic in origin. The composition of the biotites studied principally falls in the calc-alkaline subduction related I-type granite on the tectonomagmatic discrimination diagrams, which stand on their major element oxides. Which is consistent with the nature of their host rocks. The studied amphiboles are classified as calcic (ferro-hornblende) which points to the I-type nature of the granitoid. The tourmaline composition plots on the schorl - foitite field. The temperature for the alteration, on the base of chlorite composition from the syenogranite, is estimated around 350°C and from the monzogranite rocks about 341°C. Based on the application of Al-in amphibole, a 3 Kbar pressure was determined for the syenogranite unit corresponding to the depth of 8-11 Km for the emplacement of the pluton. Hornblende- plagioclase thermometer shows 694 to 700°C for the equilibrium of these two minerals.

We present the results of geological, petro‐geochemical and mineralogical studies of synplutonic intrusive formations in the Chelyabinsk granitoid massif, South Urals. Numerous synplutonic intrusions in the study area are in early phases, composed of quartz diorites and granodiorites of the Late Devonian – Early Carboniferous. Such intru‐ sions are represented by a bimodal series of rocks from gabbro‐diorite to plagioleic granite. Both the mafic and salic members of the series form separate independent dykes and, jointly, compose the dyke bodies of complex structures. With respect to the relationships with host rocks, two types of the studied dykes are distinguished: (1) ‘classical’ synplutonic dykes with monolithic bodies that are split along strike by the enclosing granodiorite into separate frag‐ ments; and (2) ‘post‐granite’ dykes that clearly break through the host quartz diorites and granodiorites that are older that the dykes, but show similar isotope ages: the U‐Pb‐Shrimp ages of zircon in the samples taken from the dyke and the host quartz diorite are 362±4 и 358±5 Ma, respectively. The first group includes the dyke of melanocratic diorite, the second – granitoid dykes and dykes of gabbro‐diorites and diorites. The intrusion of acid rocks preceded the basites and was completed after their formation. As a result of the nearly simultaneous intrusion of both, the dykes of complex structures were formed. The material compositions of mafic rocks in these two groups are significantly dif‐ ferent. The ‘post‐granite’ dioritoids are moderately alkaline. Melanodiorite in the synplutonic dyke belongs to normal alkaline rocks. It has a very high content of MgO (12.5 mass %) and is sharply enriched with chromium (~700 ppm vs. 100–350 ppm in the ‘post‐granite’ dykes). It is thus closer to sanukitoids. The acid ‘post‐granite’ dykes vary in compo‐ sition from plagoleic granite and adamellite to tonalite. They are normal‐alkaline. Their chemical compositions often do not correspond to cotectic ones. The dioritoids have nearly zero values of ɛ Nd (from +1 to –2), and the values of (87Sr/86Sr)I vary from 0.70485 to 0.70571. The granitoids are typically characterized by negative values of ɛ Nd (from –2 to –5) and, generally, more radiogenic strontium ((87Sr/86Sr)i=0.70517–0.70567). The established isotopic com‐ positions of Nd and Sr in the synplutonic dykes of the Chelyabinsk Massif give evidence of different sources for the coexisting salic and mafic melts, but do not fit a model of simple mixing of the two components.

In Northwest Anatolia, widespread magmatism developed due to collision between Anatolide-Tauride platform and Sakarya continent during Late Cretaceous-Early Tertiary period. The granitoids in Biga Peninsula are products of post-collisional magmatism following the convergence of the northern branch of Neotethyan Ocean and developed in two different stages as Eocene and Oligo-Miocene. Eocene Karabiga, Güreci, Kuşçayır and Dikmen granitoids are granite and diorite-granodiorite; Oligo-Miocene Sarıoluk, Yenice, Kestanbol, Eybek, Evciler, Çamyayla and Alanköy granitoids are diorite, granodiorite, monzonite and Q-monzonite in composition. Metaluminous and peraluminous granitoids have similar geochemical variations and exhibit post-collisional geochemical signatures. Trace element patterns are almost similar to those observed in upper crust and GLOSS (Global Subducting Sediment) patterns with depletion in high field strength (HFS) elements (Nb, Ta, Ti, Zr, Hf). But, Oligo-Miocene Sarıoluk, Yenice-Çakıroba, Kestanbol, Evciler, Çamyayla, Alanköy and Eocene Karabiga, Güreci and Kuşçayır granitoids have higher Th and U contents relative to upper crust and GLOSS. Dikmen, Yenice-Hamdibey, Yenice-Eskiyayla and Eybek granitoids have lower Th content. Geochemical variations indicate that partial melting and fractional crystallisation- crustal contamination processes are effective in their genesis and evolution. Trace element ratios also indicate subduction signatures in their genesis and Rb/Ba, Rb/Sr ratios suggest mantle melting rather than crustal melting. Accordingly, post-collisional Biga Peninsula granitoids were derived from a previously metasomatised lithospheric mantle source, which was enriched during northward subduction and closure of the northern branch of Neo-Tethys Ocean beneath the Sakarya continent, since variations in Rb, Cs, Th, La and Sm reveal that lithospheric mantle was mesomatised by both aqueous fluids and sediment melts., In Northwest Anatolia,widespread magmatism developed due to collision between Anatolide-Taurideplatform and Sakarya continent during Late Cretaceous-Early Tertiary period. Thegranitoids in Biga Peninsula are products of post-collisional magmatismfollowing the convergence of the northern branch of Neotethyan Ocean anddeveloped in two different stages as Eocene and Oligo-Miocene. Eocene Karabiga,Güreci, Kuşçayır and Dikmen granitoids are granite and diorite-granodiorite;Oligo-Miocene Sarıoluk, Yenice, Kestanbol, Eybek, Evciler, Çamyayla and Alanköygranitoids are diorite, granodiorite, monzonite and Q-monzonite in composition.Metaluminous and peraluminous granitoids have similar geochemical variationsand exhibit post-collisional geochemical signatures. Trace element patterns arealmost similar to those observed in upper crust and GLOSS (Global SubductingSediment) patterns with depletion in high field strength (HFS) elements (Nb, Ta,Ti, Zr, Hf). But, Oligo-MioceneSarıoluk, Yenice-Çakıroba, Kestanbol, Evciler, Çamyayla, Alanköy and EoceneKarabiga, Güreci and Kuşçayır granitoids have higher Th and U contents relativeto upper crust and GLOSS. Dikmen, Yenice-Hamdibey, Yenice-Eskiyayla and Eybekgranitoids have lower Th content. Geochemical variations indicate that partial meltingand fractional crystallisation- crustal contamination processes are effectivein their genesis and evolution. Trace element ratios also indicate subductionsignatures in their genesis and Rb/Ba, Rb/Sr ratios suggest mantle meltingrather than crustal melting. Accordingly, post-collisional Biga Peninsulagranitoids were derived from a previously metasomatised lithospheric mantle source,which was enriched during northward subduction and closure of the northern branchof Neo-Tethys Ocean beneath the Sakarya continent, since variations in Rb, Cs,Th, La and Sm reveal that lithospheric mantle was mesomatised by both aqueousfluids and sediment melts.

In the latter stages of exhumation processes, rocks undergo weathering. Weathering halos have been described in the vicinity of structures such as faults, veins or dykes, with a lateral size gradually narrowing with depth, symmetrically around the structures.In this paper, we describe the geophysical characterisation of such alteration patterns on two granitoid outcrops of the Catalan Coastal Ranges (Spain), each of which is affected by one major fault, as well as minor faults and fractures. Seismic, electric and ground penetrating radar surveys were carried out to map the spatial distribution of P-wave velocity, electrical resistivity and to identify reflectors of electromagnetic waves. The analysis of this multi-method and complementary dataset revealed that, at shallow depth, geophysical properties of the materials are compartmentalised and asymmetric with respect to major and subsidiary faults affecting the rock mass. This compartmentalisation and asymmetry both tend to attenuate with depth, whereas the effect of weathering is more symmetric with respect to the major structure of the outcrops. We interpret such compartmentalisation as resulting from the role of hydraulic and mechanical boundaries played by subsidiary faults, which tend to govern both the chemical and physical alterations involved in weathering. Thus, the smoothly narrowing halo model is not always accurate, as weathering halos can be strongly asymmetrical and present highly irregular contours delimiting sharp contrasts of geophysical properties.These results should be considered when investigating and modelling fluid storage and transfer in top crystalline rock settings for groundwater applications, hydrocarbon or geothermal reservoirs, as well as mineral deposits, We are grateful to ADEME (France) and EIfER (Germany) for funding this study. We would also like to thank Julien Guillemoteau (Université de Strasbourg) and Hagen Dekert (IGEM) for their help in carrying out the “espectacular” field work that provided the datasets used in this study.

The authors&rsquo, research has shown that the maximum values of 222Rn activity concentration in all granitoid massifs of Poland exceed 100 Bq&middot, L&minus, 1, i.e. the value allowed for waters intended for human consumption. Such waters should be de-radoned prior to being distributed through the water supply networks. Even more common in these areas is the occurrence of potentially medicinal radon waters, i.e. waters characterized, in accordance with Polish law, by radon activity concentration of at least 74 Bq&middot, 1. Such waters may be used for balneotherapeutic treatments. For the Karkonosze, Strzegom-Sob&oacute, tka, Kłodzko-Złoty Stok and Kudowa massifs, the range of hydrogeochemical background of 222Rn exceeds both 74 and 100 Bq&middot, 1. This indicates common occurrence in these areas of both potentially medicinal radon waters and waters which require de-radoning before being supplied for human consumption. More than 50% of groundwaters from the Karkonosze granite area contain over 100 Bq&middot, 1 of 222Rn. This means that these waters are mostly radon and high-radon waters. The remaining massifs contain predominantly low-radon waters and radon-poor waters. The 222Rn concentrations obtained by the authors are comparable to values measured in groundwaters in other granitoid massifs in the world, creating both problems and new application possibilities.

Field geological and petrographic characteristics of granitic rocks and their variants exposed at Devadurga town, Raichur district, Karnataka are described. The granitic rocks of Devadurga are part of younger 'Closepet granite' within a country of Peninsular Gneissic Complex PGC of Archaean age. Based on field and petrographic observations of this investigation, the younger granitic rocks of 'Closepet granite' within the study area can be sub divided into leucogranite, grey porphyritic granite, pink granite, pink biotite granite, grey biotite granite, pink porphyritic granite. All these granitic variants possess more or less similar mineralogical assemblages and petrographic features such as myrmekitic, perthitic signifying their magmatic origin. P. R. C. Phani | K. Sreenu | N. Ningam "Field Geological and Petrographic Study of Granitic Rocks around Devadurga, Eastern Dharwar Craton, Southern India" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, URL: https://www.ijtsrd.com/papers/ijtsrd18227.pdf

Exhumed granitoid plutons are an ideal natural research target for studying the processes of nucleation and evolution of ductile and brittle deformation structures. Granitoid plutons, unaffected by later tectono-metamorphic cycles, preserve pristine deformation structures developed during cooling from magmatic to host rock ambient temperatures, that can be assumed as representatives of structures that at different structural levels of the continental crust. The main focus of this Ph.D. project is the analysis of deformation structures of the Rieserferner pluton – one of the major Periadriatic intrusions. The aim of the study is two-fold: (i) reconstruct the tectonic framework during the different stages of the pluton structural evolution, and (ii) determine the processes controlling localized ductile strain at different scales and the environmental conditions at which they occurred. The structural evolution during pluton cooling consists of 5 main deformation stages, that have been bracketed in time and thermal conditions according to microstructural and textural analysis, literature and field data: (i) steeply dipping joints, leucocratic dykes and quartz-feldspar veins and associated ductile shear zones; (ii) shallowly dipping joints with associated epidote and quartz veins and ductile shear zones; (iii) steeply dipping mafic dykes and calcite-white mica-bearing brittle-ductile faults; (iv) steeply dipping pseudotachylyte-bearing cataclastic faults; and (v) zeolite-bearing faults. Integrating new field, microstructural and geothermo-chronological data with published data we have related the deformation sequence to the Tertiary tectonics of the Eastern Alps. (i) three main ductile deformation stages developed during Oligocene, followed by two brittle deformation stages during Miocene; (ii) paleostress inversion from kinematic analyses suggest a complex stress field variation during the structural evolution mainly due to switch in relative magnitudes of principal stress components; (iii) the described paleostress evolution reflect the sequence of tectonic processes occurred during Oligocene and Miocene at the scale of the Eastern Alps, from slab break-off to indentation and lateral escape tectonics. Microstructural investigations were mainly focused on the analysis of ductile shear zones exploiting epidote- and quartz-rich veins. Softening and localization in quartz veins was mainly controlled by grain size reduction by recrystallization. EBSD mapping and image analyses have shown that different crystallographic orientations of quartz vein crystals controlled the evolution of microstructures and crystallographic preferred orientations (CPO) during vein-parallel simple shear up to high shear strains ( ≈ 10). Recrystallization by Subgrain Rotation (SGR) lead to the development of fine-grained ultramylonitic quartz veins, in which, the observed CPO banding have been inherited from the original crystallographic orientation of the vein crystals. Localization of ductile strain within heterogeneous shear zones exploiting epidote veins was mainly obtained through myrmekite development and following shearing. EBSD investigations suggest that myrmekite induced a switch in the dominant deformation mechanism, from dynamic recrystallization by SGR to diffusion-assisted grain boundary sliding (GBS) during shearing of plagioclase + quartz aggregates. Thermodynamic modelling was aimed to define the temperature-pressure-fluid conditions under which deformation these processes occurred. Pseudosections computed for the chemical systems NaCaKFMASHO and MnNaCaKFMASHO suggest that: (i) the epidote-veining event in the RFP likely occurred at temperatures between 520°C and 490°C at water-saturated conditions; (ii) the main deformation phase likely occurred at 460±40°C and 0.35 ± 0.05 GPa, lasting probably during pluton cooling down to 350°C at slightly under-saturated water-conditions.

The Touyeh- Darvar Granitoid pluton is situated in the Eastern Alborz zone in SW of Damghan. Based on the field, petrography and geochemical studies, this pluton with monzonite and monzodiorite composition and alkaline and metaluminous to slightly peraluminous nature intruded into the lower Cambrian formations of Barut, Zaigun and Lalun in shallow depths. Petrological, geochemical and tectonic setting investigations indicate this A-type granitoid belongs to A1-subtype and has been formed in an intra-continental rift basin related to opening of the Paleo- Tethys Ocean. توده گرانیتوئیدی تویهدروار در جنوب باختر دامغان در پهنه البرز شرقی واقع شده است. بر اساس مطالعات صحرایی، پتروگرافی و ژئوشیمیایی ترکیب این توده مونزونیت و مونزودیوریت با ماهیت آلکالن و متاآلومین تا کمی پرآلومین است که درون سازندهای کامبرین زیرین باروت، زاگون و لالون در عمق کم نفوذ کردهاست. مطالعات سنگشناختی، ژئوشیمیایی و محیط زمین ساختی حاکی از این است که این گرانیتوئید نوع A وابسته به زیر گروه 1A است و در یک محیط کافتی درون قارهای مرتبط با بازشدن اقیانوس پالئوتتیس تشکیل شده است. published

TEZ11197 Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 2018. Kaynakça (s. 155-169) var. xii, 169 s. : res. (bzs. rnk.), tablo ; 29 cm. Yüksek lisans tez çalışması kapsamında zirkon/titanit U-Pb LA-SF-ICP-MS yöntemi ile Göksun (Kahramanmaraş) ofiyolitine ait okyanusal kabuk kayaçları ve bunları kesen Esence granitoyidine ait kayaçların yaşlandırılması amaçlanmıştır. Göksun (Kahramanmaraş) ofiyoliti, Türkiye'de iyi korunmuş okyanusal litosfer kalıntılarından birini oluşturmaktadır. Göksun (Kahramanmaraş) ofiyoliti Güneydoğu Anadolu orojeninde KD-GB yönelimli, metamorfik Toros karbonat platformu (Malatya metamorfik birimi) tarafından sınırlanan bir tektonik pencere içerisinde yüzlekler sunmaktadır. Göksun ofiyoliti ve Malatya metamorfik birimi Esence granitoyidi tarafından kesilmektedir. Tüm bu birimler Geç Kretase’den itibaren Güney Neotetis okyanusunun kapanmasına bağlı olarak güneye doğru hareket etmiş ve Geç Eosen döneminde Maden kompleksi üzerine bindirmişlerdir. Kabuksal kayalarda gerçekleştirilen yeni zirkon U-Pb yaşlandırması ile Göksun ofiyolitine ait kabuksal kayaların kristallenme yaşları ve magmatizmanın oluşum aralığının belirlenmesi hedeflenmiştir. Göksun ofiyolitine ait kabuksal kayalardan elde edilen zirkon mineral fazlarında gerçekleştirilen U-Pb yaşlandırması ile ~89-82 My yaş aralıkları elde edilmiştir. Esence granitoyidinin kristallenme yaşı ve Göksun ofiyoliti ile olan ilişkisini tespit etmek amacıyla yeni zirkon-titanit U-Pb yaşlandırması gerçekleştirilmiştir. Esence granitoyidlerine ait kayalardan ise ~85-77 My aralığında yaşlar elde edilmiştir. Bu veriler Güney Neotetis’te Geç Kretase’de okyanus içi yitime bağlı okyanusal kabuk oluşumu ve üzerleyen ensimatik ada yayı volkanizmasının zamanlamasının ~5-6 My olduğunu işaret etmektedir. Ofiyolit ve yay volkanizmasının oluşumundan sonra Toros platformu altına daldıkları ve sonrasında And-tipi kıta kenarında Esence granitoyidi tarafından kesildikleri anlaşılmaktadır. The aims of this study are to date oceanic crustal rocks of the Göksun (Kahramanmaraş) ophiolite as well as the intruding Esence granitoid rocks by zircon / titanite U-Pb LA-SF-ICP-MS method. The Göksun (Kahramanmaras) ophiolite constitutes one of the best preserved remnants of oceanic lithosphere in Turkey. It is exposed in a NESW trending tectonic window, bounded by the metamorphosed Tauride platform (Malatya metamorphic unit) in the nappe zone of the SE Anatolian orogeny. The Göksun ophiolite and the Malatya metamorphic unit were intruded by the Esence granitoid. These units were tectonically transported towards south due to closure of the Southern Neotethyan oceanic basin since Late Cretaceous and thrusted onto the Maden Complex in Late Eocene. Zircon U-Pb dating has been applied to the crustal rocks in order to find out crystallization age and uration of the magmatic activity for the genesis of the Göksun ophiolite. The age ranges obtained by zircon U-Pb for the crustal rocks of the Göksun ophiolites are from 89 to 82 Ma. Zircon/apatite U-Pb dating has been applied to the Esence granitoid rocks in order to find out their crystallization age and relation to the Göksun ophiolite. The ages range from 85 to 77 Ma. This evidence suggests that the suprasubduction zone-type crust and the following ensimatic island arc volcanism on top of SSZ-crust formed around 5-6 Ma time period within the southern Neotethys. After the genesis of oceanic crust and arc volcanism, they thrusted beneath the Tauride platform and all the units were intruded by Esence granitoid along the Andean type active margin. Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi tarafından desteklenmiştir. Proje No: FYL-2015-4774.

金沢大学理工研究域地球社会基盤学系, Granitoids are widespread in Precambrian terranes as well as the Phanerozoic orogenic belts, but they have garnered little attention in paleomagnetic studies, because granitoids often contain abundant coarse-grained, magnetically unstable oxides. In this study, the first example of tiny, needle-shaped, exsolved oxides in plagioclase in a Paleoarchean granitoid is reported. The magnetic properties of single plagioclase crystals with the exsolved oxide inclusions have been studied to determine their paleomagnetic recording fidelity. Demagnetization experiments and hysteresis parameters indicate that the oxide inclusions are near stoichiometric magnetite and magnetically very stable. First-order reversal curve (FORC) diagrams reveal negligible magnetostatic interactions. Minimal interactions are also reflected by very efficient acquisition of anhysteretic remanent magnetization. Single plagioclase crystals exhibit strong magnetic remanence anisotropies, which require corrections to their paleodirectional and paleointensity data. Nonetheless, quantitative consideration of anisotropy tensors of the single plagioclase crystals indicates that the bias can be mitigated by properly averaging data from a few tens of single crystals. From the nonlinear thermoremanence acquisition of the plagioclase crystals, we estimate that the plagioclase crystals can reconstruct paleointensity up to 50 μT. Local metamorphic condition suggests that those magnetite may carry remanence of ∼3.2 to 3.3 Ga. We suggest that exsolved magnetite in granitoids is potentially a suitable target for the study of the early history of the geomagnetic field, and prompt detailed microscopic investigations as well as paleomagnetic tests to constrain the age of remanence. © 2014. American Geophysical Union. All Rights Reserved.

The paper presents the results of the research, connected with the granulometric and mineralogical compositions of fusible clay raw materials of Krasnoyarsk region - argillic and loose clay varieties. The influence of granitoid and diabase rocks stony additives on the sinterability and strength characteristics of the ceramic materials based on fusible clays is evaluated. It is found that the introduction of sintering additives into the loose fusible clay leads to the significant increase of samples strength – 50-100 MPa, while the introduction of the similar additives in the argillic clay does not influence positively on samples strength.

This paper presents field geological and petrographic aspects of various granitoid units occurring around Khatgaon area in the southeastern part of Nanded district of Maharashtra. The study area is bestowed with granitoids of Archaean to Proterozoic age overlain by Deccan basalts of Cretaceous age. Three main types of granitoids were identified in the study area viz., older granites, gneissic foliated granites and younger granites. These granitoid rocks are traversed by dykes, veins and veinlets of felsic and mafic composition. Although these granitoids are similar in mineralogy, they exhibit differences in petrographic characteristics. The granitoids of the study area, especially the gneissic granitoids, comprise felsic and mafic lenticular enclaves of different sizes. Petrographically older and younger granitoids show medium to fine grained, porphyritic and inequigranular textures. The gneissic rocks show foliation. At the contact of mafic enclaves and gneissic zones, conspicuous variation in mineralogy is observed in thin sections. Presence of enclaves indicates coexistence and mixing of both felsic and mafic magmas at the source. The typical textures like perthitic, graphics and lamellar twinning indicate a direct magmatic origin for these granitoid rocks. The presence of pyrite mineralization at Khatgaon indicates late stage hydrothermal activity associated with felsic veins. P. R.C.Phani | N. Ningam | M. Srinivas "Field Geology and Petrography of Granitoid rocks in southeastern part of Nanded district, Maharashtra State" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-6 , October 2017, URL: https://www.ijtsrd.com/papers/ijtsrd4710.pdf

In this paper, we report on a compilation of more than 2200 sites (more than 10,000 individual measurements) where anisotropy of magnetic susceptibility (AMS) was studied in granites from the Variscan Pyrenees. The standardization and homogenization of this information has allowed us to produce three Main Maps that synthesize all the information related with the AMS of the Pyrenean granites. We also describe the problems found during the construction of the database (variable geo-positioning, different published information, etc.). The information derived from 21 granite bodies, the database, and the synthesis maps (magnetic susceptibility, Km, and the orientation of the magnetic foliation, plane perpendicular to k3, and of the magnetic lineation, k1) allow us to see for the first time a complete image of this important kinematic and petrographic indicator., Unidad de Zaragoza, Instituto Geológico y Minero de España, España, Departamento de Geografía y Ordenación del Territorio, Universidad de Zaragoza, España, Unidad Asociada en Ciencias de la Tierra, Instituto Geológico y Minero de España, España, Unidad Asociada en Ciencias de la Tierra, Universidad de Zaragoza, España, Departamento de Ciencias de la Tierra, Universidad de Zaragoza, España, Laboratoire Géosciences environnement Toulouse, Université de Toulouse, Francia, Laboratoire Géosciences environnement Toulouse, Centre National de la Recherche Scientifique, Francia, Laboratoire Géosciences environnement Toulouse, Institut de Recherche pour le Développement, Francia, Laboratoire Géosciences environnement Toulouse, Observatoire Midi-Pyrénées, Francia, Geodinamika Saila, Euskal Herriko Unibertsitatea, España

International audience; The crust of the Paleoproterozoic West African Craton in northern Ghana is dominantly made of Tonalite-Trondhjemite-Granodiorite (TTG) suites, low-K to high-K calc-alkaline granites, with minor LILE-enriched diorites, and chemically related lavas. Results of zircon U-Pb dating indicate that all these different rock types were formed together over a prolonged period of ca. 100 Ma, between 2.21 and 2.11 Ga. Zircon Hf isotope compositions of five samples are supra-chondritic (εHft from +1 to +6) indicating that the granitoids derive from the reworking of juvenile crustal components as old as 2.60 Ga. Geochemical data show that the TTGs were derived from the reworking of a low-K mafic crust, while biotite granites formed by the reworking of older felsic crustal rocks, and diorites derived from the melting of LILE-enriched mantle sources.The combined datasets support a three-step model for the formation of the crust of the West African craton in northern Ghana: (1) a juvenile, mafic proto-crust was extracted from the depleted mantle between 2.60 and 2.30 Ga, in an oceanic environment remote from any pre-existing continental nucleus; (2) the mafic proto-crust was reworked in several primitive magmatic arcs or in accreted oceanic plateaux. Crustal reworking initially produced minor felsic magmatism between 2.35 and 2.21 Ga, followed by the 2.21–2.15 Ga emplacement of low- to medium-P TTG and K-rich calc-alkaline granitoid suites, and was coeval with the formation of an enriched mantle source. (3) Various proto-continental terranes collided during the Eburnean orogeny between 2.14 and 2.11 Ga, triggering intense reworking of the composite crust and mantle reservoirs formed in the previous two steps, i.e. remnants of the juvenile mafic crust, older TTGs and biotite granites, and previously enriched mantle sources. The emplacement of high-P TTGs, granites and LILE-enriched diorites resulted from lower crustal heating in response to the delamination of the lower crust and lithospheric mantle. The Eburnean collision therefore marks the final stages of a 200–500 Ma long period of juvenile continental crust formation and stabilisation. The datasets further reveal that the Paleoproterozoic West African Craton comprises a minimum of two distinct crustal blocks, with north-western Ghana lying at their interface.

Granitoid outcrop has been observed in Montongan, Tulakan Subdistrict, Pacitan District, East Java. Geochemically, granitoid shows peralluminous S-type granitoid which consists of comparable plagioclase and potassium feldspar leading to adamelite and granodiorite variety with andalusite, fine size corundum and cordierite inside. These modal minerals are consistent with its bulk chemical analysis result that shows alumina rich rock. Highly weathered spotted pinkish soil with remaining quartz gravels characterizes its surface. Lateritic pink soil up to more than 25 meters thick covers the granitoid body and this feature is indicative to locate its surface distribution, while its subsurface distribution is remain uncertain. The research aimed to identify granitoid subsurface distribution. To identify the subsurface body, gravity and seismic tomography models were used. According gravity model, the pluton body is 5 km wide which is rootless downward and seems extends eastward. Meanwhile, the north-south seismic tomographic model across Pacitan Region indicates dense solid body override the recent Java subduction zone. The body is assumed to have correlation with surface granitic rock. It supports an idea that there is a micro continent trapped beneath Southern Mountain of East Java. ABSTRAK Singkapan granitoid telah teramati di daerah Montongan, Kecamatan Tulakan, Kabupaten Pacitan, Jawa Timur. Secara geokimia, granitoid Pacitan memperlihatkan granitoid peralumina tipe-S yang tersusun berdasarkan perbandingan plagioklas dan kalium felspar menunjuk pada varian adamelit dan granodiorit dengan andalusit, korundum halus dan kordierit di dalamnya. Mineral modal tersebut konsisten dengan hasil analisis kimia total yang menunjukkan batuan kaya alumina. Tanah berwarna merah muda yang sangat lapuk dengan kerikil sisa kuarsa menjadi ciri khas di permukaannya. Tanah laterit merah muda yang tebalnya lebih dari 25 meter menutupi tubuh granitoid tersebut dan menjadi petunjuk penyebaranya di permukaan, namun penyebaran di bawah permukaannya masih belum pasti. Penelitian ini bertujuan untuk mengetahui penyebaran granitoid di bawah permukaan. Untuk mengidentifikasi tubuh bawah permukaannya, digunakan pemodelan gravitasi dan tomografi seismik. Menurut model gravitasi tubuh pluton mempunyai lebar 5 km dan tampak memanjang ke arah timur yang tidak menentu ke bawahnya. Sementara itu, model tomografi seismik utara-selatan yang memotong wilayah Pacitan, menunjukkan suatu tubuh padat keras berada di atas zona subduksi Jawa saat ini. Tubuh tersebut diasumsikan memiliki hubungan dengan batuan granitik di permukaan. Hal tersebut mendukung ide bahwa terdapat mikro-kontinen terperangkap di bawah Pegunungan Selatan Jawa Timur.

Bangka Island is composed by Klabat Granite and its granitoid variations. This study aims to investigate the characteristics of granitoid Bangka Island to be applied in the study of magmatism, tectonic situations and relationships developed in granitoid for possible exploration. The methodology used by observations with a thin section of rock (petrography) and secondary major elements analysis from previous research. Granitoid samples are collected from Western, Southern, Central and East (Belinyu). Granitoid ages range from Late Permian to Late Triassic. Petrographic analysis showed dominant granitoid type as Alkali Feldspar–Syeno Granite, whereas geochemical analysis as Alkali -Syeno Granite. SiO2 variation diagram shows declining in the proportion of the major elements CaO, MgO, TiO2, Al2O3 and P2O5 with increasing SiO2 influenced by affinity fractionation as calc-alkalic magma with high K content. Affinity can be formed on continental arc where subduction and collision involved. Preliminary result granitoid typology as peraluminous, with I type. In Central and Eastern Bangka (Belinyu) characterized by high proportion of magnetite, magnesian, and more primitive, while S type in the South and West Bangka are characterized by high K2O and the presence of abundant biotite + muscovite + cordierite.

Granitoid rocks of Kaje area, northwest Ferdows, with the composition of diorite, monzodiorite, monzonite, monzogranite, syenogranite and granite, with calk-alkaline and high potassium affinities, have trace and rare earth element geochemical characteristics similar to those from subduction zones, belonging to I-type granitoid rocks. Most of these rocks are oxidized (magnetite series), while one suite is reduced (ilmenite series) showing S-type characteristics. Three samples of granitoid rocks were dated using zircon U-Pb method. Granitoid rocks belong to upper Cretaceous epoch. A granite porphyry with the age of 84.2±1.3 Ma (Santonian stage) is the oldest body followed by a biotite hornblende monzogranite of 70.8±1.4 Ma (Campanian stage) and the youngest body is a hornblende quartz diorite with the age of 67.9±1 Ma (Maastrichtian stage). Initial 87Sr/86Sr and 143Nd/144Nd ratios as well as єNdi for the granite porphyry are 0.708080, 0.512129 and -7.81, respectively. Those ratios for the biotite hornblende monzogranite are 0.706125, 0.512416 and -2.55, respectively; and for the hornblende quartz diorite are 0.707491, 0.512221 and -6.43, respectively. Based on geochemical and isotopic data, three types of granitoid can be distinguished having three different sources and characteristics. The first and oldest one is the granite porphyry of continental crust source, the second one is the monzonite and monzodiorite and the third group is the diorite of mantle source which originated and emplaced in different depths with various rates of contamination. These rocks have higher (87Sr/86Sr)i values compared with the other upper Cretaceous rocks in Bazman and Gazu areas, and lower (87Sr/86Sr)i values in comparison with the Bejestan rocks. Petrochemistry of the granite group is similar to the Bejestan rocks, but these are 10 m.y. younger and the other two groups have similar geochemistry and source to Bazman and Gazu with more contamination by the crust.

Administratively, study area is located in Sabbang, Sabbang District, North Luwu Regency South Sulawesi Province and astronomically research area is located at 120??11'00"???120??13'00" east longitude and 02??36'00"???02??38'00" south latitude with an area of 12,96 Km2. The purpose of this research, want to know the kind of granitoid rocks, content of chemical element granitoid rocks and interpretation genesis of granitoid rocks in research area with X-Ray Fluorescence Method. Based on the field research, petrographic analysis, and geochemical analysis, the granitoid rocks in research area include granite, granodiorite and granodiorite porphyry. Based on SiO2 element, in this research area have more acid to the south because of the content of SiO2 is higher to the South included High K alc-Alkaline magma series with acid magma type, for the saturation level of alumina (Shand, 1943 in Clarke, 1992), the type of granitoid is metaluminous, beside that, granitoid in this areas is the Itype granite (I-type) showed the present of mafic minerals such as pyroxene, hornblende and biotite minerals and formed in convergen zone tectonic setting environment at active continental margin with feature of the present of zircon mineral in petrographic analysis as special mineral at active continental margin and generally holocristaline texture and abundace of biotite, orthoclase and plagioclase in zoning texture.

TEZ12134 Tez (Doktora) -- Çukurova Üniversitesi, Adana, 2016. Kaynakça (s. 181-215) var. XVII, 281 s. :_rnk. res., tablo ;_29 cm. Güneydoğu Anadolu’da iyi yüzlekler sunan Helete bölgesi (Kahramanmaraş) Güney Neotetis’in Geç Kretase-Erken Senozoyik yitim süreçleri ve zamanlamasının anlaşılması açısından önemlidir. Çalışma alanındaki ana yüzlekler (~26 km uzunlukta) KD-GB uzanımlı, kuzeye eğimli bindirme dilimleri halinde Toros bindirme kuşağının alt seviyelerinde yer almakta olup, Orta Miyosen’de Arap önülkesi üzerine yerleşmiştir. Çalışma alanındaki ana birimler yapısal olarak üstten alta doğru; (1) Güney Neotetis’in kuzey kıta kenarını oluşturan ve meta-karbonatlardan oluşan Malatya metamorfikleri, (2) Geç Kretase-Orta Eosen yaşlı karbonatlar (Harami formasyonu), (3) Ofiyolitik kayaçlar (Meydan ofiyoliti), (4) Volkanik kökenli kayaçlar (Helete), (5) Tektonik melanj ve (6) Arap ön ülkesi kayaçlarından oluşmaktadır. Kuzeyde yer alan Malatya metamorfikleri ve güneyde yer alan Arap ön ülkesi hariç diğer tektonik birimler granitoyidler tarafından kesilmişlerdir. Bu çalışma Meydan ofiyoliti, Helete volkanikleri ve alttaki melanj üzerine odaklanmaktadır. Meydan ofiyoliti yapısal olarak dilimlenmiş düzensiz bir okyanusal kabuk kesiti sunmaktadır. Bunlar; ultramafik-mafik kümülatlar, izotrop gabro, levha dayk kompleksi ve volkanosedimanter kayaçlardan oluşmaktadır. Kabuksal kayaçların tüm kayaç jeokimyası ve mineral kimyası verileri yitimle ilişkili bir tektonik ortamı işaret etmektedir. Meydan ofiyolitini kesen asidik intrüzif ve ekstürizif kayaçlardan (granit, granofir, aplit ve riyolit) 83-88 My UPb zirkon yaşları elde edilmiştir. Helete birimi bazikten asidiğe doğru değişen kayaçlarla (bazalt, bazaltik-andezit, andezit, riyodasit ve dasit) temsil edilirler. Jeokimyasal açıdan Helete volkanikleri toleyitik magmadan evrimleşmişlerdir. N-MORB’a göre normalize edilmiş örümcek diyagramında negatif Nb anomalisi oldukça belirgin olup, volkanik kayaçların yitimle ilişkili bir ortamda oluştuklarını göstermektedir. Helete birimini kesen granitoyid kayaçlarından (granit, granodiyorit, tonalit, gabro, diyorit ve dasit) 86-93 My U-Pb zirkon yaşları elde edilmiştir. Melanj biriminde neritik kireçtaşı, rekristalize kireçtaşı, altere volkanik ve az oranda amfibolitik kayaç blokları serpantinitik veya volkanik kökenli matriks içinde görülmektedir. Melanj birimini kesen granitoyid kayaçlarından (granit porfir, granodiyorit porfir ve kuvarslı diyorit) 87 My U-Pb zirkon yaşları elde edilmiştir. Helete birimini kesen Geç Kretase yaşlı granitoyidler arazide haritalanabilir boyutlarda olup, stratigrafik olarak Orta Eosen yaşlı sedimanter birim tarafından örtülürler (ince bir taban konglomerası ve üste doğru Nümmülitli kireçtaşları). Bu nedenle bu çalışmada sunulan yeni izotopik yaşlar, jeolojik haritalama, yapısal ve sedimanter veriler, Helete biriminin Eosen yaşını ile ilgili yapılan yorumları ciddi anlamda sorgulamaktadır. Çalışma alanındaki tüm tektonomagmatik birimler Geç Kretase’de kuzeye dalan okyanus içi yitim zonu üzerinde oluşmuşlardır. The well-exposed Helete (Kahramanmaraş) region of SE Anatolia is critical for understanding the timing and processes of Late Mesozoic-Early Cenozoic subduction/accretion of the S Neotethys. The main outcrop (c. 26 km long) is characterized by NE-SW-trending, northward-dipping imbricate thrust slices that are located low in the stack of Tauride thrust sheets that was finally emplaced onto the Arabian foreland during the Mid-Miocene. From the structural top downwards, the main units in the study area are: (1) Malatya Metamorphic Unit, a Mesozoic meta-carbonate platform, which is interpreted as part of the northern continental margin of the Southern Neotethys; (2) Late Cretaceous-Middle Eocene carbonates (Harami Formation); (3) Ophiolitic rocks (Meydan ophiolite); (4) Volcanogenic rocks (Helete unit); (5) Tectonic melange and (6) Arabian foreland. The above tectonic units are all intruded by granitoid rocks, except the Malatya Metamorphic Unit in the north and the Arabian foreland in the south. The present study focuses on the Meydan ophiolite, the Helete unit and the underlying melange unit. The Meydan ophiolite is composed of structurally distrupted oceanic crustal rocks including ultramaficmafic cumulates, isotropic gabbros, sheeted dykes and volcanic-sedimentary rocks. Major and trace-element geochemistry, coupled with mineral chemistry, suggest a subduction-related tectonic setting for ophiolite genesis. The siliceous intrusive and extrusive rocks that cut the Meydan ophiolite (i.e. granite, granophyre, aplite and rhyolite) have yielded new U-Pb zircon ages of 83 to 88 Ma. The Helete unit is characterized by wide range of basic-silicic extrusive rocks (i.e. basalt, basaltic-andesite, andesite, rhyodacite and dacite). Geochemically, the volcanics of the Helete unit evolved from a tholeiitic parental magma. Mid-ocean ridge basalt-normalised spider diagrams of the basic extrusives display marked negative Nb anomalies, suggesting eruption in a subductionrelated setting. The granitoid rocks that cut the Helete unit (i.e. granite, granodiorite, tonalite, gabbro, diorite and dacite) give U-Pb zircon ages of 86-93 Ma. The melange unit is dominated by blocks of neritic limestone, recrystallized limestones, altered volcanic rocks and rare amphibolite, with a locally variable matrix of serpentinite or volcanogenic material. Granitoid intrusions (e.g. granite-porphyre, granodiorite-porphyre and quartz-diorite) cutting the melange unit also gave a Late Cretaceous age (87 Ma; zircon U-Pb) . Field mapping shows that the U. Cretaceous granitoid rocks that cut the Helete unit come within several tens of metres, stratigraphically overlying Middle Eocene sedimentary cover (i.e. thin basal clastics, followed by nummulitic carbonates). The new isotopic ages, coupled with field mapping, structural and sedimentary evidence, therefore, seriously question the existing interpretation of the Helete volcanic unit as Eocene in age. All of the tectonomagmatic units studied appear to have formed in a supra-subduction zone setting, above a north-dipping subduction during Late Cretaceous.

The Vaasa batholith, western Finland, is a large, peraluminous granitoid pluton that crystallized at 1.88-1.87 Ga during the culmination of the Svecofennian orogeny. The batholith has gradual contacts, through metatexites and diatexites, with the enveloping metasedimentary rocks of the Bothnian Belt. We present ID-TIMS U-Pb age data on monazite from granitoids and xenoliths of the Vaasa batholith and combine these with published U-Pb zircon ages in order to shed further light on the evolution of the Vaasa batholith. The apparent monazite ages for seven of the examined samples are 1870-1863 Ma, and 1855+/-3 Ma for one further sample from the southern part of the batholith. Combined with pre-existing data, the monazite ages of the granitoids are 9 to 18 Ma (face values) or 3 to 9 Ma (external errors considered) younger than the U-Pb zircon crystallization ages from respective samples. Our new data suggest slow cooling for the Vaasa batholith - the closure/saturation temperature of the monazite U-Pb system was probably reached in similar to 10 m.y. after the crystallization of magmatic zircon in the examined rocks. The Vaasa batholith, western Finland, is a large, peraluminous granitoid pluton that crystallized at 1.88-1.87 Ga during the culmination of the Svecofennian orogeny. The batholith has gradual contacts, through metatexites and diatexites, with the enveloping metasedimentary rocks of the Bothnian Belt. We present ID-TIMS U-Pb age data on monazite from granitoids and xenoliths of the Vaasa batholith and combine these with published U-Pb zircon ages in order to shed further light on the evolution of the Vaasa batholith. The apparent monazite ages for seven of the examined samples are 1870-1863 Ma, and 1855+/-3 Ma for one further sample from the southern part of the batholith. Combined with pre-existing data, the monazite ages of the granitoids are 9 to 18 Ma (face values) or 3 to 9 Ma (external errors considered) younger than the U-Pb zircon crystallization ages from respective samples. Our new data suggest slow cooling for the Vaasa batholith - the closure/saturation temperature of the monazite U-Pb system was probably reached in similar to 10 m.y. after the crystallization of magmatic zircon in the examined rocks. The Vaasa batholith, western Finland, is a large, peraluminous granitoid pluton that crystallized at 1.88-1.87 Ga during the culmination of the Svecofennian orogeny. The batholith has gradual contacts, through metatexites and diatexites, with the enveloping metasedimentary rocks of the Bothnian Belt. We present ID-TIMS U-Pb age data on monazite from granitoids and xenoliths of the Vaasa batholith and combine these with published U-Pb zircon ages in order to shed further light on the evolution of the Vaasa batholith. The apparent monazite ages for seven of the examined samples are 1870-1863 Ma, and 1855+/-3 Ma for one further sample from the southern part of the batholith. Combined with pre-existing data, the monazite ages of the granitoids are 9 to 18 Ma (face values) or 3 to 9 Ma (external errors considered) younger than the U-Pb zircon crystallization ages from respective samples. Our new data suggest slow cooling for the Vaasa batholith - the closure/saturation temperature of the monazite U-Pb system was probably reached in similar to 10 m.y. after the crystallization of magmatic zircon in the examined rocks.

Cilj rada bio je detaljna petrografska karakterizacija stijene s lokaliteta Mlagi Gaj, jedne od geotočaka na geološkoj karti PP Papuk.

Most skarn deposits are directly related to magmatic activity, and there is a systematic correlation between composition of causative plutons and the metal contents of the related skarns. Darreh Zerreshk deposit is located in southwest of Yazd. Petrological and geochemical studies show that Darreh Zerreshk granitoid ranges in composition from granite through quartz monzodiorite and has subalkaline, calc-alkaline and metaluminous to prealuminous characteristics like most worldwide skarn granitoids. This study shows that geochemical characteristics of the Darreh Zerreshk granotoid rocks are similar to granitoids of Millstream Cu-Fe skarn deposit in Canada, Fe skarns in British Columbia and Au-Cu skarns in the RioNarcea gold belt in Spain. The similarity between REE patterns in Darreh Zerreshk intrusion and skarns also confirms the strong petrogenetic relationship between magmatic and skarnization processes.

Bibi Maryam granitoid body with about 5 Km2 has intruded into ophiolite mélange complex in sistan suture zone, in east of Iran. Thermal effects of this body on the host rocks show that this activity occurred after emplacement of ophiolite mélange. This intrusive body with general northwest – southeast trend is mainly tonalite-quartz diorite but there is a minor unit as dykes of granodiorite in the northwest side. Main texture in tonalite - quartz diorite is granular and in granodiorite part, granular, myrmekitic and graphic are popular. Quartz, plagioclase (oligoclase-andesin) and biotite are the main minerals and the minors are amphibol, apatite, zircon and opaque in the main body. Quartz, sodium plagioclase and alkali feldspar are the main minerals and the minors are garnet, apatite and opaque minerals in granodiorite unit. Bibi Maryam granitoid is magmatic arc type and has plotted in calc-alkaline, metaluminous to peraluminous field. High ratio of LREE / HREE, Sr/Y (average is 38.7), and SiO2 amount (average is 69.48) with absent of Eu negative anomaly show these rocks are very similar to high SiO2 adakites. High ratio of Sr/Y can be interpreted of high depth melting in plagioclase unstability and garnet stability field. The source of this magma can be an eclogite or garnet amphibolites which derived of subducted metamorphosed oceanic plate in east of Iran. Dating on zircon grains in the main body (tonalite-quartzdiorite) with zircon uranium – lead shows this magmatic event has occurred at 71.5 ± 0.6 Ma (maestrichtian). Based on this dating, the emplacement of host ophiolite mélange should occurred before maestrichtian.

The Southeast Anatolian Orogen resulted from collision of the Afro-Arabian and the Eurasian plates following the Cretaceous to Miocene closure of the southern Neotethyan oceanic basin. In this orogenic belt, there are number of tectonomagmatic/stratigraphic units in the Kahramanmaraş-Malatya-Elazi{dotless}g region that are important to understand the geological evolution of southeast Anatolia during the Late Cretaceous. These are (a) metamorphic massifs (i.e. Malatya-Keban platform), (b) ophiolites (i.e. Göksun, İspendere, Kömürhan), (c) ophiolite-related metamorphics (i.e. Berit metaophiolite) and (d) granitoids (i.e. Göksun, Doganşehir and Baskil). The Baskil granitoid crops out to the northwest of Elazi{dotless}g and is a large magmatic body (170 km2) that intruded all of the above-mentioned units during Late Cretaceous time. The Baskil granitoid comprises both mafic and felsic plutonic/sub-plutonic rock associations. The felsic plutonic phase includes granite, granodiorite, tonalite and quartz monzonite whereas the felsic sub-plutonic phase is characterized by aplite, granophyre, granite porphyry and granodiorite porphyry. The granite and granodiorite contain mafic microgranular enclaves (MME). The mafic plutonic phase comprises gabbro, diorite, quartz diorite, whereas the mafic sub-plutonic phase is represented by diabase, microdiorite, quartz microdiorite, diorite porphyry, quartz diorite porphyry and dykes of orbicular gabbro dyke. Geochemically, the Baskil granitoid rocks have I-type, metaluminous-peraluminous calc-alkaline characteristics. The REE- and ocean ridge granite-normalized multi-element patterns and tectonomagmatic discrimination diagrams, together with biotite geochemistry suggest that the granitoids were formed in a volcanic arc setting. The40Ar/39Ar geochronology of the granitoid rocks yielded biotite ages of 81.9 ± 0.7 Ma and 81.5 ± 0.8 Ma (95% confidence level). Coexisting hornblende, and hornblende from additional samples, yielded ages ranging from 84.0 ± 0.7 Ma to 81.5 ± 1.1 Ma. The ophiolites are believed to have formed in a suprasubduction zone tectonic setting, whereas the ophiolite-related metamorphic rocks formed either during the initiation of intraoceanic subduction or later-stage thrusting (~ 90 Ma). These units were then thrust beneath the Malatya-Keban platform during the progressive closure of the southern Neotethys. This was followed by intrusion of the granitoids (85-82 Ma) along the Tauride active continental margin of the southern Neotethys. © 2008 Elsevier B.V. All rights reserved. Firat University Scientific Research Projects Management Unit: FBE2002-08 102Y041 This paper is a part of the PhD study of Tamer Rızaoğlu. This study was supported by two research project grants (Scientific and Technological Research Council of Turkey, TÜBİTAK with a project number 102Y041 and Niğde University Scientific Research Projects Unit, with a project number FBE2002-08). The authors would like to thank two anonymous reviewers and Alastair Robertson for suggesting improvements to the manuscript. Osman Parlak also acknowledges the financial support from the Turkish Academy of Sciences, in the frame of the Young Scientist Award Program (TÜBA-GEBİP). We are also grateful to Professor Fikret Isler for thoughtful discussions on the evolution of the granitoid bodies in the SE Anatolia.

The magnetic susceptibility of rocks is determined by their bulk chemistry and magnetic mineralogy. In this case study of the Saruhan pluton in Turkey, a detailed survey based on 925 field measurements and 37 whole rock analyses, reveals a strong correlation between magnetic susceptibility and FeOt (R2 = 0.8). Petrographic observations and calculations based on whole-rock major element analyses indicate the presence of magnetite grains. Further calculations show that magnetite accounts for 88% of the magnetic susceptibility. The spatial correlation between FeOtotal and the magnetic susceptibility is particularly spectacular which suggests that Km is a proxy for geochemical differentiation. The zoning pattern of magnetic susceptibility across the pluton is concentric and reverse, with the highest values of magnetic susceptibility in the center. This type of zoning is consistent with a previously proposed petrogenetic model. The comparison of the Saruhan granites with a classic example of paramagnetic granites reveals two contrasted FeOt-Km trends. This suggests that these variations can be a useful tool to distinguish between leucocratic paramagnetic and leucocratic ferrimagnetic granites. © 2007 Elsevier B.V. All rights reserved.

The Kashmar granitoid (42.5 Ma) occurs in NE Central Iran Plate (CIP). It mainly includes felsic metaluminous (ASI ≤ 1) I–type granite and granodiorite plutons. Microprobe analyses show that the Kashmar amphiboles are low in Ti and (Na+K)A contents (all < 0.5 apfu), indicating magnesio–hornblende, a distinct mafic mineral of low–temperature I–type granites. Also, the content of Al2O3 is low, suggesting low–pressure crystallization. The Mg* ratio is high (0.60–0.75) and the AlVI is extremely low (< 0.1 apfu), but Fe3+ is much higher than AlVI, features confirming low–pressure and low–temperature conditions. Utilizing the modern thermo–barometers, the pressures of ≤ 3 kb and average temperature of 655 oC were calculated for Kashmar amphiboles. The attributed log fO2 values are negative, ranging from –16.59 to –19.40 and plotting above the QFM stability. Results of this study propose a thermal boundary of ~700 oC between felsic (~600–700 oC) and mafic (~700–800 oC) low–temperature I–type granites, and reinforce the modern granite subdivision.

The granitoids are present in a number of the cores from oil wells drilled in the basement of the Pannonian Basin, but generally appear in the three different areas - west of the Moslavačka Mt, the eastern part of Drava depression and the Slavonia-Srijem depression (Đeletovci-Privlaka).

Oku-iwa Rock in the Liitzow-Holm Complex East Antaictica is situated in a transitional between granulite-facies and amphibolite-facies metamoiphic zones Two gianite masses, the Akai-misaki mass and the Nishi-kaigan mass are intruded into hornblende biotite gneiss (HB gneiss) in this area Rb-Sr and Sm-Nd whole rock isochron ages of the HB gneiss are 583±56 Ma and 674±22 Ma, iespectively The Rb-Sr whole rock isochion age of the Akai-rmsaki gianite mass is 485±50 Ma Some granitoids collected from the Nishi-kaigan gianite mass are plotted close to the 485 Ma ieference isochron with lowei initial^Sr/^Si ratios then the Akai-misaki gianite mass The HB gneiss was foimed from igneous rocks with gianodiontic chemical compositions and/or volcanogeneous sedimentary rocks with similai chemical compositions The HB is characterized by stromatolitic migmatitic appearances Based on present and previously published geochronological data, the following geochronological sequence for Oku-iwa Rock is estimated Stage I (674±22 Ma) was gianodioritic magmatism Stage 2 (583±56 Ma) has two possible interpretations (1) the tempeiature of gianodioiitic rocks formed at ca 670 Ma was giadually lowered and reached ca 700°C at 583 Ma, (2) refusion of granodioiitic rocks which has formed at 674 Ma took place at 583 Ma If the migmatitic portions (leucosome) in the HB gneiss was formed at 674 Ma Oku-iwa Rock must have ictained high temperature between ca 670 Ma and ca 500 Ma (U-Pb ziicon ages ca 620 Ma, 560 Ma-520 Ma) Stage 3 (485±50 Ma) was granitic magmatism Attei 480 Ma the constitutent rocks of Oku-iwa Rock cooled down piobably caused by uplifting

The Variscan syntectonic granitoid plutons from the Aguiar da Beira region (central Portugal) were emplaced into metasediments of Late Proterozoic–Early Cambrian age during the last Variscan ductile tectonic event (D 3 ), which is related to dextral and sinistral shearing. The older intrusion, with a U–Pb ID–TIMS zircon age of 321.8 ± 2.0 Ma, consists of porphyritic biotite granodiorite–granite with transitional I–S type geochemical signature, relatively low 87 Sr/ 86 Sr 322 ratios (0.7070–0.7074), eNd 322 values of − 3.9 to − 4.6 and whole-rock and zircon δ 18 O values of 10.6‰ and 8.0‰, respectively. By contrast, the younger intrusion is an S-type muscovite–biotite leucogranite, emplaced at 317.0 ± 1.1 Ma, showing more radiogenic 87 Sr/ 86 Sr 317 = 0.7104–0.7146, lower eNd 317 values of − 7.7 to − 8.7 and higher δ 18 O-wr = 11.3‰ and δ 18 O-zr = 9.5‰. The combined isotopic and geochemical evidence supports a lower crustal origin for the biotite granodiorite–granite, involving the anatexis of lower crustal metaigneous protoliths, and possible hybridization with mantle-derived magmas. A shallower origin, at mid crustal levels, from pure crustal derivation, through moderate degrees of partial melting of Proterozoic–Cambrian metasediments is proposed instead for the muscovite–biotite leucogranite.

International audience; The Archean granitoids in the Kiéné area, Gabon, are overlained by the Paleoproterozoic sediments of the Franceville basin (2.1 Ga). The basin is known for its high-grade uranium deposits among which some have been forming natural nuclear fission reactors. Most of the studies were dedicated to the FA-FB Paleoproterozoic sediments hosting these uranium deposits. Little is known on the Archean basement itself and specifically on the hydrous alteration events it experienced before and after the sediment deposition. The present work is focused on their petrographical, mineralogical and geochemical characterization. Dating the successive alteration events has been attempted on altered monazite crystals. Rocks in different alteration states have been sampled from eight drill cores crosscutting the Archean - Paleoproterozoic unconformity. The Archean granitoids observed in the deepest levels exhibit typical petrographical features of a propylitic alteration while they are intensely illitized up to the unconformity. The propylitic alteration is mainly pervasive but the original texture of the granitoïds is conserved in spite of the formation of new minerals: Mg-chlorite, allanite and epidote forming a typical paragenesis. The illitic alteration is much more invasive near the unconformity. The illitization process leads to the replacement of feldspars and the corrosion of quartz crysals by an illitic matrix while the ferromagnesian minerals are pseudomorphosed by a Fe-chlorite + phengite + hematite assemblage. The final fluid-rock interaction step is marked by fissural deposits of calcite and anhydrite. The δ13C isotopic data show that the fissural carbonates precipitated from diagenetic fluids enriched carbon products deriving from the maturation of organic matter. The U-Pb isotopic analyzes performed on monazite crystals have dated three distinct events: 3.0-2.9 Ga (magmatic), 2.6 Ga (propylitic alteration) and 1.9 Ga (diagenetic illitization). The calculation of geochemical mass balances suggests that the water-rock ratio during the propylitic alteration event was weak. On the contrary, it was much higher during the overprinted illitization which is characterized by an intense leaching of Na, Ca, Mg, Sr, REE and an enrichment in K, Rb,Cs. Neither the petrographic features nor the geochemical data militate for an Archean weathering event (paleosol). In the present case, diagenetic fluids have percolated from the unconformity into the basement where they overprinted the illitization processes upon the previously propylitized rocks. These fluids were probably oxidant as they are also responsible of the U mobilization which led to the formation of the ore deposits close to the FA-FB interface.

Wide surfaces and huge volumes of granito-gneissic basements of the Hercynian massifs are albitized from North-Africa up to Scandinavia. The supergenic origin of these facies has already been forwarded in the past. The supergenic/endogenic question has to be substantiated beyond doubt before going further in this subject. Demonstrating that the albitized facies are of supergenic origin and bound to the Triassic palaeosurface renews deeply the ideas about the evolution of the Hercynian basements. The recognition of the Triassic palaeosurface on wide basement areas of western Europa will provide a spatio-temporal bench marks to constrain the ablation of these massifs since the Trias. This will be a major contribution to the geodynamic modelling of these areas. This albitization comes with a "carbonation" of the Ca from the plagioclase feldspars. In this manner, albitisation plays a significant rule in the CO2 storage during the Trias, with regard to the giant volume of rocks in consideration. Furthermore, in the backdrop arises the questions of the specificity of this sodium-rich paleoaweathering features, find out their origin, and bound them to the giant sodium chloride accumulation during the Permo-Triassic times… is this the record of a global event ?; De vastes surfaces et volumes de socle granito-gneissique sont albitisés sur toute la chaîne hercynienne de l'Afrique du Nord à la Scandinavie. L'interprétation supergène de ces faciès a déjà avancée par le passé. La question supergène/endogène doit être établie de façon indubitable avant de pouvoir aller plus avant dans le sujet. Démontrer que les faciès albitisés sont d'origine supergène et liés à la paléosurface triasique renouvelle profondément les idées sur l'évolution des socles hercyniens. La connaissance de la paléosurface triasique sur de vastes régions de socle de l'Ouest de l'Europe fournira un repère spatio-temporel qui permettra de contraindre les taux d'ablation des massifs depuis le Trias. Elle sera une contribution majeure à la modélisation de la géodynamique de ces régions. Cette albitisation s'accompgne d'une "carbonatation" du Ca des feldspathes plagioclases. Elle intervient donc dans le stockage du CO2 pendant le Trias et ceci de manière significative, eu égard du volume des roches affectées. En toile de fond est aussi posée la question de la spécificité sodique de cette paléoaltération, en rechercher l'origine, la relier à la gigantesque accumulation de chlorure de sodium pendant le Permo-Trias, ... est-ce la marque d'un évènement global ?

A fin de profundizar en la comprensión de las interacciones entre tectónica y magmatismo en la corteza media y profunda, se ha realizado un análisis petroestructural detallado en el sector meridional de Punta dels Farallons- Volt Andrau (Cap de Creus, Pirineos Orientales). En esta zona, esquistos de alto grado fueron afectados por fusión parcial e intruídos por una secuencia de rocas magmáticas intermedias a ácidas durante la fase deformativa transpresiva varisca (D2). Tanto la tectónica regional como las características reológicas controlaron el modo de localización de la deformación en las distintas rocas del complejo migmatítico. Los esquistos y migmatitas presentan una marcada foliación sub-vertical (S2). Las medidas de deformación de venas y diques tardíos han permitido determinar la deformación regional post-emplazamiento. La transpresión dextral fue asociada a un acortamiento sub-horizontal N-S y la dirección de extensión principal pasó de sub-vertical a sub-horizontal bajo un régimen constriccional muy próximo a “plane strain”, To deepening the understanding of the interactions between tectonics and magmatism in the mid to deep crust, a detailed petrostructural analysis has been performed in the southern area of Punta dels Farallons-Volt Andrau (Cap de Creus, Eastern Pyrenees). In this area, schists under high-grade conditions suffered partial melting while a sequence of intermediate to acid magmatic rocks were emplaced during the Variscan D2 transpressive deformation event. Both regional tectonics and rheological features controlled the way deformation localized in the various rocks of the migmatitic complex. Schists and migmatites have a penetrative sub-vertical foliation (S2). Strain measurements of deformed late veins and dykes have allowed us to determine the regional deformation post-dating their emplacement. Dextral transpression was associated to N-S sub-horizontal shortening and the principal extension direction switched from sub-vertical to sub-horizontal under bulk constriction to plane strain