Türkiye Jeoloji Bülteni

Abstract: The study was able to describe the ancient landslide debris around Güzelyalı Village. Also, the remainsof horrendous ancient landslides have been discovered in northeast of Erenköy Village in Çanakkale. In this frame,aim of the study is to determine the preparatory and triggering factors that form the landslides by analyzing theoccurrence and development mechanisms of these landslides with the geological and geomorphologic methods. Theevidence for the ancient landslide triggered by 1875 Erenköy-Çanakkale Earthquake presented in this paper, which islocated near Erenköy. Ancient landslide complex around Erenköy-Güzelyalı area has the distinction of having one ofthe largest, landslides in Çanakkale. The total area of the ancient landslides is approximately 3.75 square kilometersin size. Historical landslides near Erenköy have been noticed by land features bearing two hallmark characteristics.These are: a jumbled assortment of rocks at the base of a slope, and a cuplike or sharp-straight topography cutout of the hills where the slide might have come from. Post 1875 erosion activity have partially erased much of theevidence of landslide. It was assumed that landslide deposits near Güzelyalı Village were produced by multiplelandslide events. Probably some of the slides, originated by earthquakes consisting of many events, likely several hundred years between them. Mentioned landslide debris was recently moved again as creep-type landslides. Ancientlandslide debris offers danger signs for northeastern Güzelyalı housing developments. Ancient Güzelyalı’s landslidedebris and related landslide is older than Erenköy’s landslide.

Abstract: Many scientific researches have been done on different faunal assemblages in relation to the environmentalcondition from thermal sources located on the eastern Aegean Sea coast. Aliağa (İzmir) region has also thermalresources. These two thermal springs are closely located on the coast of Ilıca Cape, northwest of Aliağa (İzmir) andnorthwest of Karaağaç Cove. Their temperatures are 40°C and 51°C, respectively. The bottom deposits consist ofrock fragments, gravel, sand, silt and clay units in the study area.In this research, 13 bottom sediment samples taken from different points and corresponding depths in the sea betweenthe Ilıca Cape and the Taşlı Cape were examined. Heavy metal analysis in the sediment samples were done by usingICP-MS. In addition, the results of trace element analysis and total Alpha and Beta features in the samples takenfrom the sea surface and spring waters were evaluated. The aim is to interpret meiobenthic living conditions byinvestigating on the effect of thermal springs the benthic foraminifera, ostracod and mollusk assemblages in thisregion.It was observed that the typical Aegean Sea foraminifera fauna composed of 32 genera and 50 species predominatedin the studied samples. An important peculiarity of the region is absence of amphistegina lobifera and peneroplidgenera and species commonly observed in the Aegean coasts of Turkey. Widely known nineteen genera and twentyeight species from Ostracods were found in Mediterranean and Aegean Sea. Mollusc faunas consist of 9 genera and10 species from gastropods, 14 genera and 14 species from bivalves.The other an important finding in the deposits are the presence of numerous gypsum crystals in sample A11. Thisfinding is an indication of an old thermal source. Furthermore, distribution of zinc (Zn), lead (Pb), Cooper (Cu) andarsenic (As) as the heavy metals in the same sample were found to be the highest. In these examples, a few speciesof foraminifera and only one species from ostracods and bivalves were found. 

Abstract: The Karakaya Complex units representing the relicts of environments related with the closure of PreJurassic Paleotethys Ocean outcrop within the Sakarya Composite Terrane. The compositions of illite/white micaschange among muscovite-illite-phengite that illite/white micas with detrital and authigenic origins are close tomuscovitic (Siavg=3.15, (Na+K)avg=0.81) and illitic compositions (Siavg=3.22, (Na+K)avg=0.74), respectively.Paragonite (Siavg=2.96, Na=0.78, K=0.10) and NaK micas (Siavg=3.09, Na=0.45, K=0.34) are typical for extentionalbasins that are determined in the upper parts of the Turhal Metamorphites corresponding to the subgreenschistfacies of the Karakaya Complex. The chlorites are of entirely trioctahedral and authigenic ones (Siavg=5.67,Feavg=5.05) have higher SiIVand lower FeVI contents in comparison with detrital ones. Chlorites have chamositicin the Hodul Unit, whereas clinochlore composition in the Orhanlar Unit. Detrital micas with high Mg (5.70-7.59)and Cr (0.09-0.16) contents are also identified in the Orhanlar Unit more common and in the Turhal Metamorphitesas a few grains that are evaluated as evidences the presence Pre-Triassique ophiolitic rocks. The data of chloritechemistry indicate the origins of felsic for Turhal Metamorphites, metabasic (probably remains of Paleotethys) for  Orhanlar Unit and felsic and metapelitic with rich in Al and extreme rich in Fe. The data of chlorite geothermometryand phengite geobarometer indicate a temperature ranging from 150 to 300 °C and a pressure between 0.5-1.2kbar, respectively. These values reflect the the high temperature-low pressure metamorphism for the upper part ofthe Karakaya Complex representing sub-greenschist facies and low-middle temperature-low pressure diagenesisconditions for sub-greenschist facies units of the Karakaya rift.

Abstract: In this study, it is aimed to determine the mineralogical and geochemical features of the rocks from theGermav Formation of Upper Cretaceous-Paleocene age belonging to Şırnak Group. The clastic and chemicaloriginated rocks of the unit show different grain size, mineralogical composition and textural relations as epiclastic(sandstone, sandstone with carbonate), pelitic (shale) and clayey-sandy carbonate (marl, sandy limestone). Rockforming minerals determined by XRD; in the order of abundance calcite, phyllosilicate / clay (chlorite, C-S, C-V,vermiculite, illite, rarely serpentine, I-C and I-V), quartz, feldspar, dolomite, hematite and goethite. According to theresults of OM, SEM and XRD examinations in the unit; there are also detrital minerals transported from metamorphicand ophiolitic units as well as diagenetic minerals. The phyllosilicate / clay minerals with different chemicalcomposition are rich in Al2O3, tFe2O3 and/or MgO. Trace element and REE concentrations are mostly observedin chlorite and least in vermiculite mineral. The contents of phyllosilicate / clay minerals when compared with thechondrite values; the patterns of the samples are distinct from each other, although the enrichments-depletions varyon the basis of the derived rocks, minerals and elements. Phyllosilicate / clay minerals exhibit significant variation/ differentiation / partition according to the chondrite and NASC compositions in terms of trace and REE contents.

Abstract: The Çöpler porphyry-epithermal gold deposit is associated with middle Eocene intrusive rocks relatedto an extensional tectonic phase in the Tethyan Alpine-Himalayan orogenic belt. The intrusive rocks (granodioriteporphyry and diorite porphyry) were emplaced in Late Paleozoic–Mesozoic metapelite and metacarbonate rockscreating the porphyry-epithermal Cu-Au deposit and hydrothermal alteration zones (potassic, phyllic, propylitic,argillic). The mineralogic-petrographic and geochemical properties of the extensive argillic alteration zones (notsupergene alteration described previously) were determined by optical and scanning electron microscopy (SEM andSEM-EDS), X-ray diffraction (XRD), O-H isotope geochemistry and K-Ar dating. Within the primary porphyritictexture, fine-grained clay and quartz crystals are present as homogeneous and partly micro-laminations in the moreintensely argillized granodiorite porphyry. Smectite and mixed-layer illite-smectite (I-S) minerals exhibit flaky/sponge-like and fibrous shapes, respectively, whereas illites and kaolinites show platy/tabular crystal shapes. Quartzand jarosite have euhedral crystals, cristobalites and crandallites (first determined here) are shown as worm-likeand fine-grained granular aggregates, respectively, developed within the pores indicating direct precipitation fromthe hydrothermal fluids. The samples from the argillic zone display quartz + I-S in the inner parts (advanced argilliczone) close to phyllic zone, whereas quartz + smectite + kaolinite associations are towards outer parts (argilliczone). Smectites have a dioctahedral composition (d060<1.500 Å, octahedral Al=1.47-1.66 a.p.f.u). I-S mineralshave a high illite component (I85-S15) with R3 type ordering of interlayering. The tetrahedral Al and interlayer Kcontents are 1.66-1.71 and 0.58-0.75, respectively. Oxygen and hydrogen isotope composition of I-S indicate thelow temperature conditions from the magmatic water dominant fluids. The data demonstrate the argillic alteration was widely distributed and developed under low temperature (<200 ºC),acidic conditions in association with the aluminum phosphate and iron phosphate minerals.

Abstract: International Committee on Stratigraphy has formed new stages in Holocene and published them recently.Earthscientists of our country should adopt and start to use new stages urgently. If they do, new stages based onglobal climate changes can be basis of joint studies between fields of cultural geology, archaelogy, geoarchaeology,pedology, palaeoclimatology etc.