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WOS: 000454048500001 The Telbesmi Formation, at the northern margin of the Arabian Plate, Turkey, is composed of alternating dark-brown, pinky-brown fluvial arkosic sandstone/mudstones with thin-bedded cherry limestones and channel conglomerates. The formation contains rare and poorly diversified trace fossils. The siltstone/sandstone beds of levels 1 and 2 of the formation yielded, however, a moderately diverse assemblage composed of: Cochlichnus isp., Palaeophycus isp., Planolites beverleyensis, Teichichnus isp. and ?Treptichnus rectangularis. This assemblage, made up of traces left by deposit feeding organisms, represents the Scoyenia ichnofacies. Treptichnus rectangularis and Palaeophycus isp., of the assemblage, can be considered markers for the base of the Cambrian in southeast Turkey. General Directorate of Mineral Research and Exploration (MTA) in Ankara [2013-30-14-19]; TUBITAK-Scientific and Technical Research Council of TurkeyTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [111Y326] This study was supported by the General Directorate of Mineral Research and Exploration (MTA) in Ankara within the frame of grant 2013-30-14-19. Additional support was provided by the TUBITAK-Scientific and Technical Research Council of Turkey (CAYDAG-Project No: 111Y326).

The Central Pontides in northern Anatolia is located on the accretionary complex formed by the closure of Neotethyan Intra-Pontide Ocean between the southern Eurasian margin (Istanbul-Zonguldak Terrane) and the Cimmerian Sakarya Composite Terrane. Among other components of the oceanic lithosphere, it comprises not yet well-dated felsic igneous rocks formed in arc-basin as well as continent margin settings. In-situ U-Pb age results for zircons from the arc-basin system (tiangaldag Metamorphic Complex) and the continental arc (Devrekani Metadiorite and Granitoid) yield ages of 176 +/- 6 Ma, 163 +/- 9 Ma and 165 +/- 3 Ma, respectively. Corresponding in-situ average (initial) Hf-176/Hf-177 initial ratios are 0.28261 +/- 0.00003, 0.28267 +/- 0.00002 and 0.28290 +/- 0.00004 for these units and indicative of a subduction-modified mantle source. The new U-Pb ages and Hf isotope data from these oceanic and continental arc units together with regional geological constraints support the presence of a multiple subduction system within the Intra-Pontide Ocean during the Middle Jurassic.

Outcrops of the Late Ordovician glacio-marine deposits in Tauride Anatolide Platform contain rare rounded/sub-rounded glacially transported granitic pebbles. Recently determined crystallization ages of the granitic fragments by LA-ICP-MS U-Pb zircon dating fall in two groups, 575 to 600 Ma and 700 to 965 Ma. Crystallization ages are in the range of juvenile magmatic rocks in the Arabian Nubian Shield except one sample implying pre-0.87 Ga magmatic activity. All dated granitic pebbles geochemically show arc-related compositions and juvenile isotopic systematics (whole rock epsilon Nd-(T), Pb-Pb and zircon epsilon Hf-(T) isotopic data). Marginal arc type sources fit well with the geochemical and isotopic data of the granitic pebbles of 700 and 800 Ma that have juvenile Hf-T-DM and older Nd-T-CR modal ages. However, A-type affinity of three samples, ranging from 575 to 600 Ma show that they might have been derived from mixing of juvenile mantle and older crustal sources having older Hf-T-DM and Nd-T-CR modal ages. A 965 Ma granitic fragment has the oldest Hf-T-DM and Nd-T-CR model age(s) implying involvement of pre-Neoproterozoic crustal source(s) in its genesis. These results collectively suggest that the glacio-marine successions in the Tauride Anatolide Platform were eroded from Neoproterozoic granitic/meta-granitic/meta-granodioritic rocks in the northern Nubian Shield (Egypt) and were then transported to the Tauride-Anatolide Platform by the glacial sheets during Late Ordovician time. (C) 2017 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

The Central Pontides (Turkey) includes several igneous complexes, which are predominantly PermoCarboniferous and Middle Jurassic in age. The Cangaldag Pluton is one of the largest igneous bodies located in the northern Central Pontides, whose age and tectono-magmatic evaluation is important to constrain the geological evolution of the Northern Neotethys. The pluton tectonically overlies the cangaldag Metamorphic Complex, which represents an arc-back-arc complex of Middle Jurassic age. The Cangaldag Pluton consists mainly of non metamorphic gabbroic diorite, dacite porphyry, and lesser amount of granitic rocks. Geochemically, the various rock types are akin to volcanic arc magmas displaying Th/Nb and light rare earth element/heavy rare earth element enrichments. In-situ U-Pb age results of zircons from dacite porphyry and granite samples yield ages of 161 +/- 5 Ma and 170 +/- 2 Ma, respectively. Corresponding in-situ average Hf-176/Hf-177 initial ratios are 0.28287 +/- 0.00004 and 0.28213 +/- 0.00002 for the dacite porphyry and granite samples, respectively. These results are consistent with derivation from a subduction-modified mantle source. Based on Hf isotope compositions, TOM model ages vary between 624 and 1512 Ma and suggest that the arc magmatism associated with the cangaldag Pluton may have involved partial melting of Neoproterozoic/Mesoproterozoic crustal rocks, a common feature in Gondwana-derived terranes. The geochemical, Hf isotope, and geochronological data reported here confirm the presence of a continental arc system during the Middle Jurassic in the Central Pontides, and suggests that the cangaldag Pluton formed during northward subduction of the Intra-Pontide branch of the Northern Neotethys. (C) 2017 Elsevier B.V. All rights reserved.

New geochemical, Sr/Nd isotope and zircon U-Pb LA-ICP-MS data from the Derik Volcanics in the Southeast Anatolian Autochthone Belt of Turkey are consistent with an Andean-type Cadomian arc that developed along the northern edge of the Arabian Plate during the Late Neoproterozoic. The Derik Volcanics represent a volcanic complex including andesites, rhyolites and basalts, with volcanoclastic and fluvial sediments. They are unconformably overlain by playa sediments with Early Cambrian ichno-fossils, followed by Middle Cambrian-Silurian shallow marine deposits.

The remnants of the Southern Neotethys are represented by ophiolitic bodies and subduction/accretion complexes along the Southeast Anatolian-Zagros suture belt in the Eastern Mediterranean. Around Malatya and Elazig areas (SE Turkey), they are found within imbricated slices of a melange complex, known as the Yuksekova Complex. The studied basaltic rocks are common members of this melange complex, and show distinctive features of sources with tholeiitic to tholeiitic-transitional character. Petrography, whole-rock trace element and isotopic data reveal two different compositional groups. Group I is transitional between island arc tholeiites and normal mid-ocean ridge basalt, and Group II includes back-arc (BABB), enriched mid-ocean ridge (E-MORB), and ocean island basalt type (OIB) compositions. According to the known Late Cretaceous stratigraphic ages, the studied basaltic rocks have (Sr-87/Sr-86)(i) = 0.7036660-0.706394, (Nd-143/Nd-144), = 0.512734-0.512927, Pb-208/Pb-204 = 38.3216-39.3400, Pb-207/Pb-204 = 15.5018-15.6262 and Pb-206/Pb-204 = 18.5655-19.3209. In addition, epsilon Nd-i values vary between +3.99 and +8.01 with two-stage T-DM values ranging from 0.25 to 0.59 Ga. In the Sr versus Nd isotope correlation diagram, most samples plot along the mantle array line. In the correlation diagrams of Pb-206/Pb-204 versus Pb-208/Pb-206 and Pb-207/Pb-206, the rock samples also plot nearly on the Northern Hemisphere Reference Line, similar to Atlantic and Pacific Ocean ridge basalts. As a whole, the isotopic data reveal that the studied rocks were derived from a depleted mantle source.

The Yuksekova melange to the NE of Van, close to the Turkish-Iranian border is part of the Berit-Elazig-Van ophiolitic belt. It structurally overlies the Bitlis-Puturge metamorphic complex and includes the remnants of the southern Neotethys. The melange complex comprises mantle rocks together with massive and pillowed lavas and dykes associated with late Maastrichtian micritic limestones and radiolarian cherts. The lavas are trachyandesite/basaltic, whereas the dykes are alkali basalt in composition. Both rock types were probably formed by low-degree partial melting of a mixed source including primitive mantle and depleted MOR mantle components, which were subsequently affected by subduction modification. The geochemical character constrains the formation of these basalts, yet the youngest ones dated in the Yuksekova melange to an intra-oceanic subduction zone within the Neotethys at the end of Cretaceous. The new ages and the tectonic setting of the volcanic rocks are correlated with other oceanic assemblages (e.g., Khoy and Inner Zagros ophiolites in Iran) across the Turkish-Iranian border.

WOS: 000346296000008, The Karadere area to the east of Safranbolu in NW Anatolia is one of the very few localities in Turkey where the contact between the Cadomian basement and the Lower Palaeozoic transgressive succession is well exposed. The Ordovician graptolite Rhabdinopora flabelliformis (Eichwald) ssp. was found in the basal part of the Bakacak Formation, indicating an Early to early Late Tremadocian age for the beginning of the Palaeozoic transgression in the Zonguldak terrane. A few metres above this occurrence, another horizon contains Paradelograptus cf. antiquus (T. S. Hall), which mainly ranges into the Late Tremadocian. Higher up in the Ordovician succession, a new graptolite bed confirms an early Darriwilian (Dw1) age for the middle part of the Karadere Formation with the occurrence of the biozonal index Levisograptus austrodentatus (Harris & Keble) and the first record of Tetragraptus cor (Strandmark) in the area. The palaeobiogeographic distribution of these Karadere fossils is in agreement with a peri-Gondwanan affinity of the Zonguldak Terrane of the Pontides, NW Anatolia, during the Early-Middle Ordovician., teams of the TUBITAK-BAS joint-projectTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [102Y157]; Spanish MINECO [CGL2012-39471]; IGCP project [591], The authors gratefully acknowledge Iskra Lakova for her contributions to a former version of this study with a divergent content. The members of the Turkish (G. Saglam, I. Gedik, N. Ozgul) and Bulgarian (I. Boncheva, S. Yanev and Y. Maliakov) teams of the TUBITAK-BAS joint-project No. 102Y157 are acknowledged for their involvement during the field studies. Participation of J. C. G.-M. was possible through the project CGL2012-39471 of the Spanish MINECO. This paper has benefited from the review of P. S torch (Prague) and J. Maletz (Berlin) and is a contribution to IGCP project 591.

A hydrothermal breccia zone 6 km long and 2 km wide, crossed by quartz-tourmaline veins, occurs to the south of the Late Cretaceous Kerkenez granite-monzonite massif in the northern part of the Central Anatolian Crystalline Complex, Yozgat, Turkey. This breccia zone is characterized by numerous veins, a few millimeters to 1 meter in width, and display typical microtectonic features of multiple brecciation. Trace amounts of albite, K-feldspar, epidote, muscovite and rutile are associated with quartz and tourmaline. Petrographic features indicate three successive stages of tourmaline generation. The first generation is represented by feruvite, and the second and third generations consist of schorl. These distinct generations of tourmaline show successive enrichment in Al and Na, and depletion in Ti and Ca. The Na/(Na + Ca) values vary in the range 0.41-0.49 in the first generation, and 0.53-0.86 and 0.91-0.99 in the second and third generations. The development of the breccia zone and formation of three successive generations of tourmaline are most probably related to fluid-assisted brecciation and infiltration of low- to medium-pH hydrothermal fluids under subsolidus conditions. Successive enrichment in Na and Al in the younger generations is ascribed to late-stage fractionation in the B-rich granitic source.

WOS: 000351706000005, The Triassic Karakaya Complex (KC) of the Sakarya Composite Terrane in northern Turkey is traditionally subdivided into two units. The Lower Karakaya Complex (LKC) consists of a tectonic m,lange with blocks of metabasic rocks, metacarbonates, meta-arenites and metapelites that have been affected by high pressure/low temperature metamorphism. It is followed by a low pressure/low temperature metamorphic overprint; the latter is the only metamorphic event in some tectonic slivers of the LKC. The Upper Karakaya Complex (UKC) units are primarily composed of diagenetic to low-grade metamorphic rocks, comprising Late Permian and Triassic cherts and blocks of OIB-type volcanic rocks interfingering with Anisian limestones. LKC slide-blocks of variable sizes are frequently observed within the UKC. Phyllosilicates of LKC and UKC were examined for their abundance, crystallinity, polytype and b cell dimension. Trioctahedral chamositic chlorites have IIb polytype and phengites 2 M (1) polytypes in the LKC units and 2 M (1) + 1 M + 1M (d) polytypes of phengitic dioctahedral illites in the UKC units. Kubler index data correspond to the low anchizone and epizone for the LKC units, and to the high diagenesis-low anchizone, and in part to the epizone for the UKC units. The b values of illites are consistent with a high-pressure facies series for the LKC, but only intermediate-pressure facies for the UKC. According to textural features, mineral paragenesis, clay transformations, index minerals, and b values, the lower-middle parts of the LKC represent an accretional tectonic setting, whereas the UKC units reflect pressure temperature conditions of an extensional basin affected by high heat flow., Scientific Research Project Fund of Cumhuriyet University [M-301], This study was sponsored by a grant from the Scientific Research Project Fund of Cumhuriyet University under project number M-301. The authors greatly appreciate the efforts of the deceased M. Duru (MTA General Directorate) and A. Gokce (Cumhuriyet University) during the field study stage of this research in the Biga and Turhal regions, respectively. We also thank the technical staff members of the Department of Geological Engineering of Cumhuriyet University for their invaluable assistance in XRD analysis and thin-section preparations. We are also very grateful to F. Nieto and an anonymous referee for their constructive comments, Editor in Chief Johann G. Raith for his corrections and suggestions and Sibia Proofreading for its editing services.

WOS: 000312268800005, The Istanbul Terrane along the Black Sea coast in NW Anatolia, is a Gondwana-derived continental microplate, comprising a well-developed Paleozoic succession. Petrographic and X-ray diffraction studies were performed on rock samples from measured sections throughout Ordovician-Carboniferous sedimentary units. Diagenetic-very low-grade metamorphic clastic (shale/mudstone, siltstone, sandstone) and calcareous rocks (limestone, dolomite) mainly contain phyllosilicates, quartz, feldspar, calcite, dolomite, hematite and goethite minerals. Phyllosilicates are primarily represented by illite, chlorite, mixed-layered chlorite-vermiculite (C-V), chlorite-smectite (C-S) and illite-chlorite (I-C). Feldspar is commonly present in the Ordovician and Carboniferous units, whereas calcite and dolomite are abundant in the Silurian and Devonian sediments. The most important phyllosilicate assemblage is illite + chlorite + I-C + C-V + C-S. Illite and chlorite-bearing mixed layer clays are found in all units. The amounts of illites increase in the upper parts of the Silurian series and the lower parts of the Devonian series, whereas chlorite and chlorite-bearing mixed-layers are dominant in the Ordovician and Carboniferous units. Kubler index values of illites reflect high-grade anchimetamorphism for the Early Ordovician rocks, low-grade metamorphism to high-grade diagenesis for the Middle Ordovician-Early Silurian rocks and high-grade diagenesis for the Late Silurian-Devonian units. The K-white micas b cell dimensions indicate intermediate pressure conditions in the Early Ordovician-Early Silurian units, but lower pressure conditions in the Middle Silurian-Devonian units. Illites are composed of 2M(1) +/- 1M(d) polytypes in all units, except for Upper Ordovician-Lower Silurian units which involve 1M polytype in addition to 2M(1) and 1M(d) polytypes. The 2M(1)/(2M(1) + 1M(d)) ratios rise from Devonian to Ordovician together with the increasing diagenetic-metamorphic grade. Chlorites have IIb polytype. In general, crystal-chemical data of clay minerals in the Istanbul Terrane show a gradual increase in the diagenetic/metamorphic grade together with increasing depth. The new data presented in this work indicate that the diagenetic/metamorphic grade of the Paleozoic of the Istanbul Terrane is higher than that of the neighboring Zonguldak Terrane and generated by a single metamorphic phase developed at the end of Carboniferous. This finding contrasts with the metamorphic history of the neighboring Zonguldak Terrane that displays a distinct Early Devonian unconformity and a thermal event., Cumhuriyet University [M-358], The study is supported by the Scientific Research Project Fund of the Cumhuriyet University under the project number M-358. Dr. Mehmet Cemal Goncuoglu gratefully acknowledges the contribution of the members of MTA-BAS Project Group for some unpublished data on the stratigraphy of NW Anatolian Paleozoic. Michel Faure and the anonymous referee are gratefully acknowledged for their constructive comments on the manuscript. We also appreciate for helpful suggestions and critical comments by Rafael Ferreiro Mahlmann and Sebastien Potel as guest editors. The authors would also like to express thanks to Ibrahim Gedik for valuable assistance during field studies and to Fatma Yalcin and Ufuk Kus, who kindly performed the XRD analysis and thin-section preparations.

WOS: 000301876000001, The Zonguldak terrane is a Gondwana-derived continental microplate along the Black Sea coast in northwest Anatolia. It includes a Cadomian basement, with oceanic-and island-arc sequences, unconformably overlain by siliciclastic rocks of Ordovician to Middle Silurian age. After a period of deformation and erosion, late Lower Devonian (Emsian) quartzites and shallow-marine limestones unconformably cover Middle Silurian (Wenlock) graptolitic shales. Along several cross sections across the unconformity plane, the mineralogical characteristics of the Paleozoic sedimentary rocks in the Zonguldak terrane are studied to check whether this regional unconformity is only of epeirogenic nature or the result of a thermal event. In addition to the appearance of kaolinite in Devonian units, crystal-chemical data of illites show a sudden jump at the unconformity plane. The b cell dimension values of illites of Ordovician-Silurian units are somewhat higher than those of Devonian-Carboniferous units and show a drastic drop between the Silurian and Devonian units. The new mineralogic data indicate that the pre-Emsian rocks in the Zonguldak terrane experienced a thermodynamo event, prior to the Emsian transgression. This Caledonian-time event is also reported in east Moesian terrane but not noticed in the neighboring Istanbul-Zonguldak and in the west Moesian Balkan - Kreishte terranes. By this, it is suggested that Zonguldak and east Moesian terranes behaved independently from the Istanbul-Balkan terranes during the closure of the Rheic Ocean. They very likely docked to Laurussia during Emsian by strike-slip faults and remained thereon at its platform margin, where the Middle-Late Devonian shallow-platform conditions were followed by fluvial (lagoon and delta) conditions and deposition of coal during Late Carboniferous., Cumhuriyet University [M-358], The study is supported by the Scientific Research Project Fund of the Cumhuriyet University under project number M-358. Dr. M.C. Goncuoglu gratefully acknowledges the contribution of the members of the MTA-BAS project group for some unpublished data on the northwest Anatolian Paleozoic stratigraphy. The authors would like to express their thanks to Fatma Yalcin and Ufuk Kus who kindly performed the XRD analysis and thin-section preparations.

WOS: 000241898700006, In the Sandikli-Afyon area, the very low-grade metamorphic Sandikli Basement Complex with elastic sediments and Late Neoproterozoic felsic igneous rocks are unconformably overlain by a cover succession with red continental elastic rocks, tholeiitic basalts and siliciclastic rocks with Early Cambrian trace fossils. Illite crystallinity studies reveal that both the basement and cover units were metamorphosed at high anchizonal to epizonal conditions (similar to 300 degrees C). Textural data together with the detailed evaluation of the P-T-b(0) grid, however, indicate that this thermal event has multiple phases. The first tectonothermal event was realized at pressures of similar to 4.2 kb on the basis of b(0)-data and resulted in development of blastomylonites. This is supported by the presence of dynamo-metamorphosed pebbles within the basal conglomerates of the Lower Paleozoic cover series. The second event is post-Ordovician-pre-Jurassic in age, occurred at lower pressures similar to 3.2 kb and produced a weakly developed cleavage in the siliciclastic rocks of the cover. The mineralogical/textural data across the basement-cover boundary therefore indicate the removal of an entire metamorphic zone and thus a metamorphic hiatus. These data suggest that the Taurides were affected by a Late Neoproterozoic event as part of the peri-Gondwana during the Cadomian orogeny. (c) 2006 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

WOS: 000274869600006, Pozzolanic activity of clinoptilolite, the most common natural zeolite mineral, was studied in comparison to silica fume, fly ash and a non-zeolitic natural pozzolan. Chemical, mineralogical and physical characterizations of the materials were considered in comparative evaluations. Pozzolanic activity of the natural zeolite was evaluated with various test methods including electrical conductivity of lime-pozzolan suspensions; and free lime content, compressive strength and pore size distribution of hardened lime-pozzolan pastes. The results showed that the clinoptilolite possessed a high lime-pozzolan reactivity that was comparable to silica fume and was higher than fly ash and a non-zeolitic natural pozzolan. The high reactivity of the clinoptilolite is attributable to its specific surface area and reactive SiO(2) content. Relatively poor strength contribution of clinoptilolite in spite of high pozzolanic activity can be attributable to larger pore size distribution of the hardened zeolite-lime product compared to the lime-fly ash system. (C) 2009 Elsevier Ltd. All rights reserved., Scientific and Technological Research Council of Turkey [104M393], This study was funded by The Scientific and Technological Research Council of Turkey under Project Number: 104M393. The instrumental analyses in this study were carried out in Middle East Technical University Central Laboratory. Acknowledgment is given to Emeritus Professor P. Kumar Mehta from the Civil and Environmental Engineering Department at the University of California, Berkeley, for his helpful comments during the investigation.

Symposium on Diagenesis and Low-Grade Metamorphism -- APR, 2001 -- STRASBOURG, FRANCE, WOS: 000177970600015, The paleogeographic and diagenetic-metamorphic evolution of Lower Paleozoic (meta-) sedimentary rocks in the Eastern Taurus Autochthon were studied by means of petrographic and XRD methods. Parameters such as illite crystallinity index, b(0) and % 2M(1) proportion of K-white micas are characterized by an increase in grade from diagenesis at the top to epizone at the bottom. Organic data show a good correlation with phyllosilicate crystal chemical parameters. Three main zones and five sub-zones with distinct breaks at boundaries were distinguished throughout the Lower Paleozoic series. These boundaries seem to correspond to stratigraphic gaps, unconformities and/or irregularities that may have important implications regarding as yet unknown deformation events. The data indicate that the Eastern Taurus Autochthonous Unit was initially not only affected by typical sedimentary burial, but also preserved vestiges of an earlier regional thermal and/or deformational history. Alpine tectonic movements and related deformations caused but limited textural changes, thus did not completely erase some fingerprints of the Paleozoic mineralogic and organic transformations. The metamorphic evolution and relationships between the mineralogic, textural and organic properties and stratigraphic/metamorphic discontinuities in the Lower Paleozoic succession are controlled by diagenetic-metamorphic reactions and detrital input related to orogenic activity in the hinterland.