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Thirty seven floor sediment samples of Upper Pleistocene age from the Loutra Almopias Cave were collected from different beds and stratigraphic columns on the basis of their induration grade, grain distribution, and paleontological findings. Channel facies make up the bulk of the clastic sediments found in the cave passages. Slackwater facies compose the final layer of all the stratigraphic sections of the examined cave. The floor sediments are mineralogically immature, since they contain many ferromagnesian minerals, feldspars (especially plagioclase) and quartz. The extensive presence of silicate minerals means that the phyllites, gneisses, schists, ophiolitic rocks and the clastic Mariam Formation of the Almopia Zone are the main detrital load source, along with the flysch of the neighboring Pelagonian Zone. The presence of sand-sized grains, pebbles and cobbles of dolomitic or calcitic composition also designates the carbonate rocks of the Almopia and Pelagonian Zones as primary sources. The dolomite and calcite content of secondary chemical origin in the cave sediments is very limited. Kutnohorite, isomorphous with dolomite, was found for first time in a Greek cave. The provenance of the sediments is mixed; they are composed mainly of the weathering materials of the Alpine metamorphic basement and the carbonate rocks outcropping adjacent to the cave. The sediments were transported and deposited inside the cave, after rapid weathering and erosion of the surrounding rocks, under a tectonically active regime. The mineralogical variation in the stratigraphic columns demonstrates variations in the clastic load, due to the different weathering intensity periods. Most of the sediments are fluvial deposits, and one is considered a glacial deposit. Fossils of Lepus timidus (mountain hare) found within the cave represent the southernmost record of this species in Europe. Its presence signifies a cool phase at the end of the last glacial period before the onset of the warm Holocene Epoch.

Various types of deposits such as carbonate-replacement Pb-Zn-Ag-Au, porphyry Cu-Mo-Au, stratiform volcano-sedimentary, isolated magmatic-hydrothermal and skarns compose the Serbomacedonian-Rhodope Metallogenic Belt (SRMB), which intersects with a NNW-SSE trend the Balkan Peninsula. This arcuate belt is about 500 km long and 130-180 km wide. Sb-Bi alloys and Ag-Cu-Pb-Sb-Bi sulfosalts have been discovered in some metal assemblages in the SRMB. The European Union (EU) is highly dependent on critical and rare metals, such as Sb and Bi, which are very important for a sustainable development. Greece is one of the EU countries with the most potential for supplying the strategic metal Sb in the future, since it hosts a significant ore deposit at Rizana/Lachanas (central Macedonia). Here, the stibnite reserves are 5,000 t (proven) and 50,000-100,000 t (indicated). Both have average Sb=0.3 wt%. In addition, at the same district, there are 1000 t (proven) of wolframite. Another promising Sb-bearing mineral assemblage exists at Alshar (North Macedonia). Here, the stibnite reserves are >20,000 t (indicated) with average Sb=0.5 wt%. At both mineralization districts further investigations are needed to determine the grade and the proven reserves of the critical metal Sb. Until today none encouraging site has been located in the SRMB for remarkable Bi-bearing ore.

Fifteen (15) zeolitic rocks from Karlovassi-Marathokampos basin of Samos Island (Greece) were investigated for their mineralogical composition by X-Ray Diffraction (XRD) method. According to EU Regulation No 651/2013, clinoptilolite of sedimentary origin with ≥80 wt% clinoptilolite, ≤20 wt% clay minerals, free of fibres and quartz, can be used as feed additive for all animal species. Depending on the zeolites, the zeolitic rocks are grouped to those containing: Clinoptilolite (33-86 wt%), clinoptilolite (59 wt%) + mordenite (20-21 wt%), clinoptilolite (22 wt%) + analcime (29 wt%), clinoptilolite (17 wt%) + phillipsite (27 wt%), analcime (29-70 wt%), mordenite (62%) and chabazite (63 wt%). None of the clinoptilolite-containing rocks (10 samples) meet the requirements of the EU Regulation No 651/2013, and thus cannot be used as feed additives for all animal species and consequently as nutrition supplements, since all of them contain 2-5 wt% quartz, two of them 20-21 wt% mordenite (fibrous zeolite), nine of them 20 wt% clay minerals (27-42 wt%). Although the EU Regulation No 651/2013 refers to clinoptilolite of sedimentary origin, using the presence or absence of quartz and fibrous minerals, none of the five mordenite, analcime and chabazite containing zeolitic rocks, can be used as feed additives and nutrition supplements, since all of them contain 2-6 wt% quartz and one of them contains 62 wt% mordenite (fibrous zeolite).

The genesis and the physical characteristics of the Neogene red beds of the cedar hills surrounding Thessaloniki are studied in this paper. The peri-urban forest, which covers these hills, has a 3,022 ha area. The topographic relief is smooth and is divided in eight small drainage basins, tapped through small creeks. The elevation of the surrounding hills varies between 85 and 560 m. The dominant land slopes vary between 20 and 55%. All the samples are coarse grained, poorly sorted and friable and present earthy lustre and red colour because of the extensive presence of iron oxides. Angular to sub-angular rock fragments derived from the metamorphic bedrock are very common. Petrographically, the studied red beds belong to the clayey sands. The extended presence (41-66%) of coarse silt and sand size grains (>20 pm) in the samples suggests a mild intensity of in situ weathering of the bedrock. X-ray diffraction analysis of the coarsest fractions 250-20 pm and 20-2 μιτι revealed in decreasing abundance the presence of quartz, feldspars, epidote, micas, chlorite, pyroxenes, amphiboles, and talc. These fractions contain the 2M polytype of mica, while in the fraction

Clastic sediments collected from land and gulfs of Macedonia and Thrace in Greece are examined on the basis of their texture and mineral composition. All terrestrial samples are coarse-grained and poorly sorted, with angular to sub-angular grains. These are mainly composed of quartz and feldspars, followed by micas, calcite and Fe-Mg minerals. Among the clay minerals illite predominates over smectite and smectite over vermiculite (+chlorite+kaolinite). In addition, the interstratified phases illite/smectite, chlorite/vermiculite, and smectite/vermiculite are present in significant amounts in the clay fraction (

Today Greece produces and exports raw bauxite and alumina, concentrates of galena and sphalerite and ferronickel. The indicated reserves of bauxite, located in the Mt Helikon-Mt Parnassus-Mt Giona-Mt Iti zone, are estimated at approximately 100 mt and those of aluminum 2.5 mt. The probable and indicated reserves of lead and zinc from Chalkidiki are approximately 3.125 mt. The total production of concentrates of galena and sphalerite is approximately 220,000 tpa. The proven reserves of nickel are approximately 1.392 mt and the production of ferronickel is approximately 18,500 tpa. Production of copper, silver and gold is pending in 2015. The probable and indicated reserves of copper from Skouries Chalkidiki are approximately 1.943 mt. In the Prefecture Units of Chalkidiki and Evros the probable and indicated reserves of gold are approximately 19.37 million ounces and those of silver 131.6 million ounces. Chromium, manganese and molybdenum present good prospects of exploitation. Calculated at current prices, the total gross value of the probable and indicated reserves of the metallic minerals of Greece is €79.4 billion.

Modern sand samples were collected from the Vertiskos Unit of the Serbomacedonian Massif, northern Greece, and were examined for their texture and mineralogical composition. They were collected from active channels and torrents. The textural study demonstrated that these modern sands are moderately to very-poorly sorted, often polymodal in grain size distribution, texturally and mineralogically immature to submature, and consist of coarse-grained gravelly sands to slightly-gravelly muddy sands. The dominant composition is quartzofeldspathic. All samples contain detrital minerals of metamorphic origin, mainly amphibole and garnet, in addition to minor amounts of pyroxene and detrital calcite. These sediments were deposited rapidly and close to their source, the metamorphic basement of the Vertiskos Unit. The mineral constituents of the samples indicate that the Vertiskos Unit is undergoing rapid physical weathering due to the temperate and seasonal climate. The results of this study suggest that these modern sands constitute one sedimentary petrologic province comprised of primarily of amphibole-garnet.

Intensive exploration of probable conventional hydrocarbon reservoirs in Greece is taking place, through the interpretation of seismic profiles and of abundant surface geological data. The unconventional hydrocarbon potential of the country is unknown, as detailed investigations are lacking. The most important rock formations which may contain shale gas are found in the land and offshore basins of northeastern, north-central, and western Greece. A re-evaluation of the data from all boreholes is needed, on the basis of new information, with the aim of identifying possible reserves of unconventional hydrocarbons retained in highly compacted fine-grained strata. Methane hydrates have been detected in the submarine Anaximander Mountains, east of Rhodes Island. They cover an area of about 46 km 2 and the volume of methane is estimated at 2.6–6.4 trillion m 3 . The low content of the Greek lignites in gaseous hydrocarbons and the widespread tectonics in the Hellenic Peninsula are the main factors which prevented large gas accumulations in its 14 main coal deposits. However, additional research is needed to evaluate the coal-bed gas potential of the country.

The Thermaikos Gulf constitutes the NW part of the North Aegean Sea and is limited eastward from the Chalkidiki Peninsula and westward from the Pieria Prefecture. Its plateau covers an area of 3,500 km2. The mechanisms responsible for the grain size distribution into the Gulf, the clay mineralogy and the chemistry of some bottom sediments from the outer Thermaikos Gulf, are examined. Source mixing during transportation, flocculation, differential settling processes and organic matter appear to be the main mechanisms for the distribution of clay minerals in shallow waters. All grain size fractions studied present a wide range of values confirming the extreme variations of the discharged load and the variability in marine processes. Plagioclases predominate over K-feldspars, while quartz is the most abundant mineral present. In addition, micas, chlorites, amphiboles and pyroxenes exist as primary and/or accessory minerals in all samples. Among clay minerals, illite predominates over smectite and smectite over chlorite (+ kaolinite). The ordered interstratified phase of I/S, with 30-35% S layers, is present in the 2-0.25µm fraction. The randomly interstratified phase of I/S, with 50% S layers, is present in the

Η μεταλλογενετική ζώνη Alpine-Balkan-Carpathian-Dinaride (ABCD), η οποία τεκτονικά εξελίχθηκε κατά τη διάρκεια του τέλους του Κρητιδικού έως σήμερα, είναι η κύρια μεταλλογενετική επαρχία της Ευρώπης, ιδιαίτερα για το χρυσό. Τρεις χωρικά διακριτές τεκτονικές και μεταλλογενετικές ζώνες συσχετίζονται με αυτή τη ζώνη. Μία από αυτές είναι η Σερβομακεδονική-Ροδοπική Μεταλλογενετική Ζώνη (SRMB), η οποία διατέμνει με κατεύθυνση ΒΒΔ-ΝΝΑ τις νοτιοανατολικές Βαλκανικές χώρες. Αυτή η ζώνη περιλαμβάνει τις γεωτεκτονικές ζώνες του Βαρδάρη (Αξιού), της Περιροδοπικής, και τις Μάζες της Σερβομακεδονικής και Ροδοπικής. Περιλαμβάνει κυρίως κοιτάσματα μετάλλων αντικατάστασης ανθρακικών ή πορφυρικά, στρωματόμορφα ηφαίστειο ιζηματογενή κοιτάσματα, skarns και ποικίλα απομονωμένα μαγματικά υδροθερμικά κοιτάσματα. Τα πιο σημαντικά κέντρα μεταλλογένεσης χρυσού αυτής της ζώνης βρίσκονται στη Βουλγαρία (π.χ. Madjarovo, Ada Tepe, Madan, Lozen), Ελλάδα (π.χ. Λόφος Περάματος, Σάπες, Μαρώνεια, Ολυμπιάδα-Στρατώνι-Σκουριές, Γερακαριό-Βάθη-Ποντοκερασιά), Π.Γ.Δ.Μ. (π.χ. Buchim, Ilovitza, Alshar), Κόσοβο (π.χ. Trepca) και Σερβία (π.χ. Lece District: Kiseljak, Bakrenjaca). Τα 2038 αποθέματα μετάλλων όλων των κατηγοριών στη SRMB είναι 24 t Au, 14 t Ag και >100 Mt κοιτάσματος (Pb+Zn) στη Βουλγαρία, 743 t Au, 4100 t Ag, 5345 th.t Cu και 3125 th.t (Pb+Zn) στην Ελλάδα, 106 t Au, 96 t Ag και 834 th.t Cu στην Π.Γ.Δ.Μ., >150 Mt κοιτάσματος (Pb+Zn) στο Κόσοβο, 118 t Au και 1270 th.t Cu στη Σερβία. Επιπλέον μέσα σ’ αυτή τη ζώνη υπάρχουν πολλές άλλες περιοχές οι οποίες είναι πολύ ελπιδοφόρες για πολύτιμα μέταλλα, The Alpine-Balkan-Carpathian-Dinaride (ABCD) metallogenic belt, which tectonically evolved during Late Cretaceous to the present, is Europe’s premier metallogenic province, especially for gold. Three spatially distinct tectonic and metallogenic belts are associated with this belt. One of them is the SerbomacedonianRhodope Metallogenic Belt (SRMB) which intersects with a NNW-SSE trend the south eastern Balkan countries. This belt includes the geotectonic zones of Vardar (Axios), Circum-Rhodope, and the Serbomacedonian and Rhodope Massives. It comprises dominantly carbonate replacement or porphyry metal deposits, stratiform volcanosedimentary deposits, skarns and various isolated magmatic-hydrothermal deposits. The most significant Au metallogeny centers of this belt are found in Bulgaria (i.e., Madjarovo, Ada Tepe, Madan, Lozen), Greece (i.e., Perama Hill, Sapes, Maronia, Olympias-Stratoni-Skouries, Gerakario-Vathi-Pontokerasia), F.Y.R.O.M. (i.e., Buchim, Ilovitza, Alshar), Kosovo (i.e., Trepca), and Serbia (i.e., Lece District: Kiseljak, Bakrenjaca). The metal reserves of all categories in the SRMB are 24 t Au, 14 t Ag and >100 Mt (Pb+Zn) ore in Bulgaria, 743 t Au, 4100 t Ag, 5345 th.t Cu and 3125 th.t (Pb+Zn) in Greece, 106 t Au, 96 t Ag and 834 th.t Cu in F.Y.R.O.M., >150 Mt (Pb+Zn) ore in Kosovo, 118 t Au and 1270 th.t Cu in Serbia. In addition many other sites inside this belt exist which are very promising for precious metals.

Τριάντα δύο (32) θέσεις ζεολιθικών πετρωμάτων της Θράκης (29 της ΠΕ Έβρου και 3 της ΠΕ Ροδόπης) μελετήθηκαν ως προς την ορυκτολογική τους σύσταση με την μέθοδο της περιθλασιμετρίας ακτίνων Χ (XRD). Σύμφωνα με τον Kανονισμό της ΕΕ αριθ. 651/2013, κλινοπτιλόλιθος ιζηματογενούς προέλευσης (ζεολιθικοί τόφφοι) με ≥80% κ.β. κλινοπτιλόλιθο, ≤20% κ.β. αργιλικά ορυκτά, χωρίς ίνες και χαλαζία, μπορεί να χρησιμοποιηθεί ως πρόσθετη ύλη ζωοτροφών για όλα τα ζωικά είδη. Τα ζεολιθικά πετρώματα της Θράκης κατά μέσο όρο περιέχουν, 23 89% κ.β. ζεόλιθο τύπου- HEU (κλινοπτιλόλιθο-ευλανδίτη), 8-45% κ.β. μορντενίτη (δέκα θέσεις), 24% κ.β. ανάλκιμο (μία θέση), 1-11% κ.β. μαρμαρυγία, 1-11% κ.β. αργιλικά ορυκτά, 3-37% κ.β. χαλαζία, 2-29% κ.β. χριστοβαλίτη, 3-34% κ.β. αστρίους και 0-22% κ.β. άμορφα υλικά. Μόνο μία θέση περιέχει 89% κ.β. ζεόλιθο τύπου-HEU (κλινοπτιλόλιθο-ευλανδίτη), 2% κ.β. αργιλικά ορυκτά, είναι χωρίς ίνες, αλλά δυστυχώς περιέχει 3% κ.β. χαλαζία και 2% κ.β. χριστοβαλίτη. Λαμβάνοντας υπόψη την ορυκτολογική σύσταση, τα ζεολιθικά πετρώματα της Θράκης δεν πληρούν τις απαιτήσεις του Kανονισμού της ΕΕ αριθ. 651/2013, και γι’ αυτό δεν μπορούν να χρησιμοποιηθούν ως πρόσθετη ύλη ζωοτροφών για όλα τα ζωικά είδη και επομένως ως συμπληρώματα διατροφής, επειδή τα ζεολιθικά πετρώματα όλων των θέσεων, περιέχουν κατά μέσο όρο 3-37% κ.β. χαλαζία, 2-29% κ.β. χριστοβαλίτη, 8-45% κ.β. μορντενίτη (ινώδη ζεόλιθο) σε 10 θέσεις, 24-65% κ.β. ζεόλιθους (τύπου-HEU ± μορντενίτη ± ανάλκιμο) σε 28 θέσεις, 74% κ.β. ζεόλιθο τύπου- HEU σε 2 θέσεις και 77% κ.β. ζεόλιθο τύπου-HEU σε 1 θέση., Thirty two (32) locations of zeolitic rocks from Thrace (29 from Evros prefecture and 3 from Rhodope prefecture) were investigated for their mineralogical composition by X-Ray Diffraction (XRD) method. According to EU Regulation No 651/2013, clinoptilolite of sedimentary origin (zeolitic tuffs) with ≥80 wt% clinoptilolite, ≤20 wt% clay minerals, free of fibres and quartz, can be used as feed additive for all animal species. The zeolitic rocks of Thrace on average contain, 23-89 wt% HEUtype zeolite (clinoptilolite-heulandite), 8-45 wt% mordenite (ten locations), 24 wt% analcime (one location), 1-11 wt% mica, 1 11 wt% clay minerals, 3-37 wt% quartz, 2-29 wt% cristobalite, 3-34 wt% feldspars and 0-22 wt% amorphous materials. Only one location contains 89 wt% HEU-type zeolite (clinoptilolite-heulandite), 2 wt% clay minerals, is free of fibres, but unfortunately it contains 3 wt% quartz and 2 wt% cristobalite. Considering the mineralogical composition, the zeolitic rocks of Thrace do not meet the requirements of the EU Regulation No 651/2013, and thus cannot be used as feed additives for all animal species and consequently as nutrition supplements, since the zeolitic rocks in all locations, contain on average 3-37 wt% quartz, 2-29 wt% cristobalite, 8-45 wt% mordenite (fibrous zeolite) in 10 locations, 24-65 wt% zeolites (HEU-type ± mordenite ± analcime) in 28 locations, 74 wt% HEUtype zeolite in 2 locations and 77 wt% HEU-type zeolite in 1 location.

Extensive metasomatic zones of vermiculite-, tremolite-, chlorite-, and talc-rich rocks have been developed at the contacts of serpentinized ultramafic bodies and surrounding two-mica gneisses in the Askos area, Macedonia, Greece. These zones are probably related to the intrusion of acid magmatic bodies in the area. X-ray and EPMA studies confirmed the formation of vermiculite through a layer-by-layer transformation of original micas. In decreasing abundance, the following mixed-layer and discrete phases were identified: biotite/trioctahedral vermiculite (hydrobiotite), biotite/smectite, trioctahedral chlorite/trioctahedral vermiculite (corrensite), vermiculite/smectite and discrete biotite, vermiculite, chlorite and talc. The 2–20 μm fraction of the vermiculitic samples consists mostly of biotite/vermiculite (>40%) with the biotite percentage dominating in the mixed phase. Lower abundances (20–40%) of biotite/smectite and chlorite/vermiculite occur in both finer fractions (2–20 and

The purpose of this paper is to establish the possible industrial applications of Griva kaolin. This kaolin comes from the alteration of gabbroic rocks from the Griva area, Macedonia, Greece. Mineralogically, the kaolin is composed mainly of kaolinite associated with vermiculite and plagioclases, and traces of quartz, amphiboles, halloysite and smectites. The kaolin grain-size analysis shows that the kaolin is mostly finer than

Ακατέργαστος ελληνικός βωξίτης από το μεταλλείο της Κλεισούρας (Νομός Φωκίδας) που περιέχει 72% κ.β. διάσπορο, 16% κ.β. αιματίτη, 6% κ.β. χαλαζία, 4% κ.β. ανατά- ση και 2% κ.β. ασβεστίτη, χρησιμοποιήθηκε για την απομάκρυνση της χρωστικής «πράσινο του μαλαχίτη» από υδατικά διαλύματα. Τα πειράματα τύπου batch εκτελέ- στηκαν σε διάλυμα 10 ml, σε pH = pHZPC = 6,7 και χρόνο επαφής 1 h. Η αρχική συ- γκέντρωση της χρωστικής «πράσινο του μαλαχίτη» ήταν 10 mg/l, ενώ οι ποσότητες του βωξίτη ήταν 0,02 g, 0,04 g, 0,06 g, 0,1 g και 0,2 g. Η μεγαλύτερη προσροφητική ικανότητα που παρατηρήθηκε ήταν 4,50 mg/g (90% απομάκρυνση) με τη χρήση 0,02 g βωξίτη. Η ικανότητα του ακατέργαστου βωξίτη στην απομάκρυνση της χρωστικής, είναι συγκρίσιμη με άλλα μη συμβατικά προσροφητικά, όπως πριονίδι από δέντρο neem, σκόνη ζαχαροκάλαμου και στάχτη ριζών καλαμιών., Raw bauxite from Klisoura mine (Prefecture of Fokida, Greece) containing 72 wt.% diaspore, 16 wt.% hematite, 6 wt.% quartz, 4 wt.% anatase and 2 wt.% calcite, has been used for the removal of malachite green dye from aqueous solutions. The batch type experiments were conducted with 10 ml of solution, at pH = pHZPC = 6.7 and contact time 1 h. The initial concentration of malachite green dye was 10 mg/l, the bauxite quantity was 0.02 g, 0.04 g, 0.06 g, 0.1 g and 0.2 g. The highest adsorption capacity achieved was 4.5 mg/g (90% removal) using 0.02 g bauxite. The removal capacity of raw bauxite is comparable to other non-conventional adsorbents, such as neem sawdust, sugar cane dust and cane root carbon.

The Eocene zeolite-bearing volcaniclastic sediments (Ca-rich clinoptilolite 51 % on average) of Metaxades, Thrace, Greece, are studied in terms of geology and chemical composition. The alternating formations along a vertical profile in the Metaxades main quarry face are: Discrete horizons of zeolite-bearing volcaniclastic tuffs, zeolite-bearing volcaniclastic tuffs including pebbles, zeolite-bearing volcaniclastic tuffs including thin silica-rich layers, and a calc-clayey horizon. A positive correlation is observed between MgO and CaO in the volcaniclastic tuffs including silica-rich layers. Sr, Rb and Ba are the most abundant trace elements in alllayers; among them, Sr is found to correlate positively with zeolite. The enrichment of sorne trace elements is mainly attributed to mineral abundances, mineral chemistry or leaching processes. The zeolite-bearing volcaniclastic sediments of Metaxades represent an inhomogeneous sequence, which was deposited in a shallow marine environment under turbulent to quiet sedimentary conditions.Los sedimentos eocenos volcanoclásticos con zeolita (51% de media de clinoptilolita rica en Ca) de Metaxades, Tracia, Grecia, se estudian desde el punto de vista geológico y de su composición química. Las formaciones alternantes que se pueden observar en un corte vertical en la cantera principal de Metaxades son: horizontes aislados de tufos volcanoclásticos con zeolita y con delgadas capas ricas en sílice, y un horizonte calco-arcilloso. Se observa una correlación positiva entre MgO y CaO en los tufss volcanoclásticos que presentan capas ricas en sílice. El Sr, el Rb y el Ba son los elementos traza más abundantes en todos los horizontes. Entre ellos, el Sr presenta una correlación positiva con la zeolita. El enriquecimiento en algunos elementos traza se atribuye esencialmente a las abundancias de los minerales, la química mineral, o a fenómenos de lixivinción. Los sedimentos volcanoclásticos con zeolita de Metaxades representan una secuencia inhomogénea, que fue depositada en un ambiente marino somero, bajo condiciones desde turbulentas hasta tranquilas.

Modern sand samples were collected from the Vertiskos Unit of the Serbomacedonian Massif, northern Greece, and were examined for their texture and mineralogical composition. They were collected from active channels and torrents. The textural study demonstrated that these modern sands are moderately to very-poorly sorted, often polymodal in grain size distribution, texturally and mineralogically immature to submature, and consist of coarse-grained gravelly sands to slightly-gravelly muddy sands. The dominant composition is quartzofeldspathic. All samples contain detrital minerals of metamorphic origin, mainly amphibole and garnet, in addition to minor amounts of pyroxene and detrital calcite. These sediments were deposited rapidly and close to their source, the metamorphic basement of the Vertiskos Unit. The mineral constituents of the samples indicate that the Vertiskos Unit is undergoing rapid physical weathering due to the temperate and seasonal climate. The results of this study suggest that these modern sands constitute one sedimentary petrologic province comprised of primarily of amphibole-garnet. © Versita sp. z o.o.

The hydrothermal and weathering alteration products of the gabbroic rocks at Griva, Macedonia, Greece, are examined using petrographic, mineralogical and chemical data. The kaolin crusts have a thickness of 1 to 8 m and extend over an area of about 5 km 2 . Many gabbro-pegmatitic veins crosscut the semi-friable kaolins. The crusts have not been intensively washed and thus the primary minerals exist within the weathered profile in significant amounts. Essential constituents are plagioclase, actinolite, clinopyroxene, clinozoisite, dolomite, kaolinite, corrensite and pyrophyllite, with varying proportions in the different particle size fractions. The 18 O values. According to the classification of Konta the kaolins studied are of the low grade type and probably only suitable for the ceramic industry.

The conditions of alteration of the upper Eocene zeolite-bearing volcaniclastic sediments at Metaxades, Thrace, Greece, were examined using a variety of petrographic and mineralogical techniques. A fine silt- to clay-size matrix, containing abundant altered glass shards, predominates. The primary minerals include quartz, K-feldspar, plagioclase, micas (especially biotite) and some opaque minerals. The diagenetic phases, clinoptilolite, smectite and cristobalite, occur as microcrystalline aggregates within the matrix or as replacements of glass shards. The abundances of cristobalite and clinoptilolite are related chiefly to the original composition of the rocks. The abundance of cristobalite increases and that of clinoptilolite + smectite decreases as the abundance of the matrix increases. The formation of clinoptilolite and cristobalite took place either at near-surface temperatures or at slightly elevated temperatures (lower than 70°C). The smectite content of the altered volcaniclastics decreases with increasing depth in the 15 m thick exposed section. No other systematic variation in mineral assemblages with depth was observed. However, the ratio clinoptilolite/smectite increases systematically with depth suggesting to us that smectite may have formed subsequent to the formation of clinoptilolite and as an alteration product of clinoptilolite. The initial composition of the volcanic material and to a less extent the interstitial fluids, greatly affected the diagenetic mineral assemblages of the final alteration products.

Στην εργασία εξετάζονται τα Νεογενή ερυθροστρώματα των Μουδανιών και Ποτίδαιας Χαλκιδικής για να προσδιοριστούν οι συνθήκες κάτω από τις οποίες σχηματίστηκαν. Είναι χαμηλού βαθμού συνεκτικότητας και φτωχά ταξινομημένα ιζήματα. Γωνιώδη έως υπογωνιώδη θραύσματα πετρωμάτων που προέρχονται από τα γειτονικά μητρικά πετρώματα είναι πολύ συνηθισμένα. Τα ερυθροστρώματα είναι ιστολογικά και ορυκτολογικά ανώριμα. Τα περισσότερα δείγματα είναι χαλικώδεις άμμοι. Η εκτεταμένη παρουσία κόκκων μεγέθους άμμου (>0,063 mm) στα εξεταζόμενα δείγματα δη- Χώνει υψηλή ένταση αποσάθρωσης των μητρικών πετρωμάτων και ραγδαία μεταφορά και απόθεση των υλικών αποσάθρωσης κοντά στην περιοχή προέλευσης. Τα κλαστικά ορυκτά που υπάρχουν στα ολικά δείγματα με μειούμενη αφθονία είναι: χαλαζίας, άστριοι (πλαγιόκλαστα + ορθόκλαστα), μαρμαρυγίες (+ αργιλικά ορυκτά), πυρόξενοι, αμφίβολοι, σιδηροπυρίτης και αλίτης (εκτός από δύο δείγματα που είναι πλούσια σε ασβεστίτη). Στο, The Neogene red beds from Moudania and Potidea (Chalkidiki) are studied in order to find the conditions under which they were formed. They are incoherent coarse grained sands, with poorly sorted grains. Angular to sub-angular rock fragments derived from the adjacent parent rocL· are very common. The red beds are texturally and mineralogically immature. Most of the samples are gravel sands. The extended presence of sand size grains (>0.063 mm) in the samples suggests high intensity of weathering of the parent rocks and rapid transportation and deposition of the weathered materials close to the source area. The detrital minerals present in the whole samples in decreasing abundance are quartz, feldspars (plagioclase + orthoclase), mica (+clay minerals), pyroxene, amphibole, pyrite and halite (except two samples which are rich in calcite). In the

Τα ιζήματα που αναλύονται είναι γενικά αδρόκοκκα, από αμμώδη χαλίκια έως χαλικώδεις άμμοι. Το περιεχόμενο τους σε ιλύ και άργιλο είναι μικρό, ενώ η ιστολογική τους μελέτη αποκαλύπτει περιβάλλον ποτάμιας απόθεσης. Το περιεχόμενο τους σε χαλαζία, αστρίους και θραύσματα πετρωμάτων κυμαίνεται από 33% έως 56%, 8% έως 18% και 28% έως 52%, αντίστοιχα. Τα ιζήματα που εξετάζονται μπορούν να ταξινομηθούν ως γρανατο-μαρμαρυγιούχοι λιθαρενίτες. Χαλαζίας, πλαγιόκλαστα και μαρμαρυγίες είναι τα επικρατέστερα συστατικά. Κλαστικός ασβεστίτης και πυρόξενοι βρίσκονται σε μικρά ποσά. Τα δείγματα είναι ιστολογικά και ορυκτολογικά ανώριμα. Λεπτομερής πολωτική μικροσκοπία αποκάλυψε την παρουσία γρανάτη, σταυρόλιθου, κυανίτη, ζοϊσίτη, ρουτιλίου, επιδότου, ζιρκονίου, απατίτη και τουρμαλίνη, καθώς και αδιαφανών ορυκτών. Αυτά τα επουσιώδη ορυκτά θεωρούνται δείκτες μεταμορφικής προέ^σης. Γεωχημικά τα δείγματα ταξινομούνται ως υπολιθαρενίτες και υποαρκόζες και όλα είναι πλούσια σε SiÖ2- Το συνολικό ποσοστό του χαλαζία, των αστρίων και των θραυσμάτων των πετρωμάτων δείχνει έντονη φυσική αποσάθρωση και ραγδαία μεταφορά και απόθεση στη Λεκάνη του Χέρσου που θεωρείται τμήμα ενός παθητικού ηπειρωτικού περιθωρίου (ανακυκλωμένο ορογενές)., The sediments analysed are generally coarse grained, sand gravels to gravel sands. The silt and clay content of the samples is low and their textural study revealed a fluvial deposition environment. The amounts of quartz, feldspars and lithic fragments range from 33% to 56%, 8% to 18% and 28% to 52%, respectively. The samples studied may be classified as garnet-mica bearing litharenites. Quartz, plagioclases and micas are the predominant constituents. Detritai calcite and pyroxenes are present in small amounts. The samples are texturally and mineralogically immature. Detailed polarized microscopy revealed the presence of garnet, staurolite, kyanite, zoisite, routile, epidote, zircon, apatite and tourmaline, as well as of opaque minerals. These accessory minerals are considered indexes of metamorphic provenance. Geochemically the samples are classified as sublitharenites and subarkoses, all being rich in Si02- The overall percentages of quartz, feldspars and rock fragments designate intense physical weathering and rapid transport and deposition in the Herso Basin which is part of a passive continental margin (recycled orogen).