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A Late Cretaceous ensimatic arc developed during closure of the northern branch of Neo-Tethys(central-northern Turkey)

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Geoscience Frontiers 2019年第3期10卷 1015-1028页

作者： Metin Beyazpirin? Ali Ekber Ak?ay Ali Yilmaz Meftun Kerem S?nmez Geological research Department General Directorate of Mineral Research and Exploration (MTA) Department of Environmental Engineering Engineering Faculty Cumhuriyet University

Studies on differentiation of ensimatic arc units from melange units in the Northern Anatolian Ophiolitic Belt(NAOB) are very rare. The study area represents the southern edge of the central part of the *** aim of the study is to distinguish the main units of NAOB and to define the geotectonic setting of the Darmik Ensimatic Arc Association(DEAA). To study the ensimatic arc units as an independent tectonic unit is important and facilitates understanding of the geological evolution of the NAOB. During field studies, the contact relationships within the Darmik Ensimatic Arc Association(DEAA) units and also with other tectonic units were reviewed. Then, paleontological, geochronological, petrological and also geochemical properties of the DEAA have been defined. In the present study, ensimatic arc units have been distinguished from ophiolitic association for the first time, in the region. As a result of the study, the DEAA is divided into two levels and lower level named as the Kartal unit and upper level named as the izibüyük unit. In the Kartal unit, basaltic and andesitic lavas with their equivalent pyroclastic rock units are dominant. Radiolarite and mudstones interbedded within the Kartal unit of DEAA have Turonian and Santonian age. In addition, the age of basalt samples of DEAA are 98.7 ± 2.4 Ma, defined using the^(40)Ar/39 Ar method. The izibüyük unit of DEAA comprises conglomerate, sandstone, claystone, mudstone,clayey limestone, micritic limestone with volcanic interbeds and also calciturbidites. Santonian-Maastrichtian ages were obtained from this unit of the DEAA. In conclusion, the age of DEAA is widely accepted as Late Cretaceous. After the evaluation of the analysis, the volcanics of the DEAA originated from calcalkaline-basalts, which reflect ensimatic arc magmatism.

关键词： North Anatolian Ophiolitic Belt Double subduction zones Darmik ensimatic arc Turkey

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Fluid Inclusion Studies and Geochemistry of Rare Earth Elements of Hydrothermal Fluorites from Pohrenk,Kirsehir,Central Turkey

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Acta Geologica Sinica(English Edition) 2001年第1期75卷 59-65页

作者： Sükrü KOC Ali RECBER Geology Department Ankara UniversityAnkara 06100Turkey general directorate of mineral research and exploration Ankara

Fluorite mineralization occurs along fractures and cracks of Middle Eocene and Pliocene limestones and marls in the north and northeast of the P?hrenk region (?i?ekdagi, Kirsehir). Tb/Ca – Tb/La and Y/Ho ratios were obtained from REE contents of fluorites which have revealed that mineralization is of hydrothermal type. Negative Ce anomalies and positive Eu anomalies reflect that hydrothermal solutions once had high oxygen fugacity. Fluid inclusion studies indicate that homogenization temperatures of mineralization varied between 90°C and 200°C, and hydrothermal solutions are composed of NaCl + KCl + MgCl2 + H2O. In addition, salinity measurements show that hydrothermal solutions were mixed with meteoric or rock formation water. Geologic setting, REE geochemistry and fluid inclusion studies suggest that mineralization was deposited from a solution generated by mixing of magmatic and meteoric water under epithermal conditions.

关键词： fluorite rare earth elements fluid inclusions

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Surface radioactive anomalies at Srisailam sub basin,Cuddapah basin,India

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Chinese Journal Of Geochemistry 2015年第2期34卷 265-271页

作者： Vishnu Bhoopathi S.Niranjan Kumar R.S.N.Sastry B.Srinivas Department of Applied Geochemistry Osmania University Atomic mineral directorate for exploration and research

Surface radioactive survey has been carried with portable gamma ray spectrometer(PGRS) about the 45 km2 around the Srisailam sub basin,the surface radioactive anomalies were found at Chennakesavula gutta in the Srisailam sub basin of Cuddapah basin in the age of meso-neo proterozoic,*** integrated geochemical and radiometric surveys were conducted as part of research work in the Srisailam basin,it has resulted the locating of surface radioactive anomalies near the Chennakesavula *** uranium minerals are observed along with the fracture planes in the Archean basement granite in the proximity of unconformity contact of Srisailam *** granite underlies the Srisailam formation and forms the source for possible unconformity related uranium mineralisation in the Srisailam sub-basin evidence by the significant radioactive *** radioactivity recorded by PGRS reflected uraniferous nature of the radioactivity(Average total counts =195 ppm;U = 202 ppm;Th =22ppm;%K = 4.1,n = 15).

关键词：放射性异常表面印度分盆 γ射线谱仪放射性调查 m盆地地球化学

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Composition of Pancarli Magmatic Ni-Cu±(PGE) Sulfide Deposit in the Cadomian-Avalonian Belt, Eastern Turkey

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Journal of Earth Science 2020年第3期31卷 536-550页

作者： Esra Yildirim Nail Yildirim Cahit Donmez Kurtulus Gunay Taner Korkmaz Mustafa Akyildiz Burcu Goren Firat University Department of Geology EngineeringElazig 23119Turkey general directorate of mineral research and exploration of Turkey Department of Mineral Research and ExplorationAnkara 06520Turkey Cukurova University Department of Geology EngineeringAdanaTurkey

Pancarli Ni-Cu±(PGE)sulfide deposit occurs in the Neoproterozoic basement complex of the Bitlis massif,which is one of the Andean-type active continental margin fragments with arc-type assemblages represented by the Cadomian orogenic *** sulfides are associated with quartzo-feldspathic gneisses(country rock)and mafic intrusions(host rock).Composed of only semi-massive ore,the Ni-Cu±(PGE)sulfide deposit is a small-scale deposit,and it does not contain net-textured and disseminated *** mineral assemblage comprises pyrrhotite,pentlandite,and *** semi-massive ore samples contain 2.2 wt.%-2.9 wt.%Ni,0.8 wt.%-2.2 wt.%Cu(Cu/(Cu+Ni)=0.2-0.5)and 0.13 wt.%-0.17 wt.%*** Cu/Ni ratios(average 0.57)are consistent with the segregation of sulfides from a basaltic *** Pt+Pd100%S values of 0.08 ppm-0.89 ppm,relatively low Pt/Pd ratios of 0.2-1.4,and Pd/Ir ratios of 4.5-39 have also been *** values demonstrate that the magma reached S saturation before its emplacement and the mineralization with high Cu/Pd ratios formed by sulfides segregated from a PGE-depleted magma.δ^34S isotope values(average-3.1‰)of Pancarli sulfides are lower than mantle ***δ^34S value indicates contamination from surrounding *** the composition,remobilization style and magma type,the Pancarli Ni-Cu±(PGE)sulfide deposit is similar to the deposits associated with Andean-type magmatic arcs located in the convergent plate margin settings.

关键词： Ni-Cu±(PGE)sulfide deposit δ^34S isotopes Neoproterozoic Andean type eastern Turkey

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Petrogenesis of the ükapili Granitoid and its Mafic Enclaves in Elmal Area (Nigde, Central Anatolia, Turkey)

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 738-748页

作者： Hüseyin KURT Kerim KOAK Kürsad ASAN Mustafa KARAKAS Department of Geological Engineering Seluk University Central Anatolia directorate of mineral research and exploration

The Late Cretaceous Uckapth Granitoid including mafic microgranular enclaves intruded into metapelitic and metabasic rocks, and overlain unconformably by Neogene ignimbrites in the Ni^de area of Turkey. It is mostly granite and minor granodiorite in composition, whereas its enclaves are dominantly gabbro with a few diorites in composition. The Uckapdl Granitoid is composed mainly of quartz, K-feldspar, plagioclase, biotite, muscovite and minor amphibole while its enclaves contain mostly plagioclase, amphibole, minor pyroxene and biotite. The Uckapth Granitoid has calcalkaline and peraluminous （AJCNK= 1.0-1.3） geochemical characteristics. It is characterized by high LILE/HFSE and LREE/HREE ratios （（La/Lu）N 3-33）, and has negative Ba, Ta, Nb and Eu anomalies, resembling those of comsion granitoids. The {）fkaplh Granitoid has relatively high STSr/S6Sr0） ratios （0.711189--0.716061） and low eNd（t） values （-5.13 to -7.13）, confirming crustal melting. In contrast, the enclaves are tholeiitic and metaluminous, and slightly enriched in LILEs （K, Rb） and Th, and have negative Ta, Nb and Ti anomalies; propose that they were derived from a subduction-modified mantle source. Based on mineral and whole rock chemistry data, the Uckapth granitoid is H-（hybrid） type, post-collision granitoid developed by mixing/mingllng processes between crustal melts and mantle-derived mafic magmas.

关键词： H-type granitoid mafic enclave geochemistry Central Anatolia Turkey

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A Computational Investigation of the Thermohydraulics of an EGS Project

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Journal of Thermal Science 2018年第5期27卷 405-412页

作者： BENIM Ali Cemal CICEK Aydin EKER Arif Mert Department of Mechanical and Process Engineering Center of Flow Simulation (CFS) Düsseldorf University of Applied Sciences Department of Energy Raw Materials and Survey General Directorate of Mineral Research and Exploration HD Energy Inc.

A numerical analysis of the thermohydraulics of an enhanced geothermal system project is presented. The rock structures are modelled as porous medium, based on the computationally obtained hydraulic fracturing data of other authors. The influence of the domain size, grid resolution, temporal resolution and the discretization scheme is assessed to obtain a highly accurate numerical solution under the prevailing modelling assumptions. Based on the numerical model, different production scenarios are investigated and discussed. The relative positioning of the injection and production ports is also analyzed. It is shown that there is a considerable potential for optimizing the production rate and the port configuration to obtain the most favorable results for the production temperature, investment costs and operation costs.

关键词： enhanced geothermal system hot dry rock thermohydraulics numerical analysis

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Changes in carbon stocks of soil and forest floor in black pine plantations in Turkey

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Journal of Forestry research 2021年第1期32卷 339-347页

作者： SükrüTeoman Güner Dilek Güner general directorate of Forestry Research Institute for Forest Soil and Ecology26160 EskisehirTurkey

The objectives of this study were:(1)to determine carbon stock changes in the soil and forest floor of black pine(Pinus nigra ***)plantations in Turkey;(2)to determine the effects of thinning on annual carbon accumulation in both;and,(3)to investigate relationships between annual carbon storage in soil and forest floor and stand characteristics of black *** were taken in 90 plots from stands at the pole(dbh=11.0–19.9 cm)and sawlog(dbh=20.0–35.9 cm)*** analyses of soil and forest floor samples showed that in unthinned plantations signifi cant organic carbon was sequestered an average of 1.47 Mg ha^−1 a^−1 in the soil and 0.20 Mg ha^−1 a^−1 in the forest *** carbon sequestered annually in the soil was signifi cantly lower in thinned than in unthinned stands,while diff erences in the forest floor were insignifi *** were positive correlations between carbon sequestered in the soil and stand age,average DBH,mean stand height,basal area,and site *** sequestered the forest floor increased with basal *** a result,carbon sequestered in the soil should not be ignored in greenhouse gas inventories because carbon stored belowground was approximately 70%of the aboveground pool.

关键词： Pinus nigra Belowground Forest floor Carbon sequestration Thinning

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Determination of discontinuities in marble blocks via a nondestructive ultrasonic technique

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International Journal of minerals,Metallurgy and Materials 2009年第5期16卷 487-493页

作者： Ahmet Hakan Onur Sefa Bakrac Faculty of Engineering Mining Engineering DepartmentDokuz Eylul University35160 Tinaztepe BucaIzmirTurkey MSc in Mining Engineering Turkish General Directorate of Mineral Research and ExplorationIstanbul Cad. No.63 Bornova IzmirTurkey

Miners working in the marble industry have always been interested in identifying structural weaknesses in marble blocks before they are transported to marble processing plants. To achieve this difficult task, several simple methods have been developed among miners but observation-based methods do not consistently provide satisfactory results. A nondestructive method developed for testing concrete could be used for this purpose. In this study, this simple method based on differences in ultrasonic wave propagation in different materials was presented, and the test results performed both in the laboratory and a marble quarry were discussed.

关键词： nondestructive test marble discontinuity ultrasonic wave

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Permo–Triassic and Liassic Tethyan Oceanic Tracts within the Pontide Belt Along the Southern Margin of Eurasia, Northern Anatolia

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 33-34页

作者： E.SARIFAKIOGLU Y.DILEK M.SEVIN S.PEHLIVAN O.K EMIR A.MOLLER T.BAYANOVA I.UYSAL M.KELES general directorate of mineral research & explor Department of Geology & Env.Earth Science Miami University The University of Kansas Department of Geology Geol.Inst.of the Kola Science Centre of the RAS Dept.of Geol.Engineering Karadeniz Technical University Makro Yet.Madencilik

The Pontide belt in northern Turkey includes three major tectonic terranes,the Strandja Massif（Sj M）,and the Istanbul（ISZ）and Sakarya Zones（SZ）(Fig.1).We present new age and geochemical data from ophiolites and ophiolitic mélanges within the Sakarya Zone and show that these mafic–ultramafic rocks are the remnants of Tethyan oceanic lithosphere formed in different tectonic *** main ophiolite occurrences investigated in this study along the Karakaya Suture（KS）are associated with the latest Triassic Cimmeride orogeny,and in the Küre–Yusufeli ophiolite belt are part of the Alpide *** Karakaya Suture Zone ophiolites in northern west Turkey are comprised mainly of the Denizgoren（?anakkale）ophiolite,Bo?azk?y（Bursa）,Geyve（Sakarya）,Almac?k（Düzce）and?ele（Bolu）*** Denizg?ren ophiolite largely contains upper mantle peridotites,which are equivalents of the Permo–Triassic Lesvos peridotites and mélange units farther SW in the northern Aegean *** Bo?azk?y ophiolite includes serpentinite and metagabbro,and the Almac?k and Geyve ophiolites display an almost complete Penrose–type sequence consisting of serpentinizeduppermantleperidotites,cumulate ultramafic–mafic rocks,isotropic gabbros,dolerite and plagiogranite dikes,and extrusive rocks.U–Pb zircon dating of plagiogranite dikes from?ele has revealed an igneous age of 260 Ma,and 255,235,227 Ma from Almac?k（Bozkurt et al.,2012a,b）.Consistent with the previouslypublished Permo–Triassic age,we obtained a 268.4±6.3 Ma U–Pb zircon age from a plagiogranite dike within the Almacik ophiolite to the *** KS ophiolite belt containing the?ele,Almac?k,Geyve ophiolites within the SZ extends westward into the Armutlu Peninsula and then into the Biga Peninsula（***?ren ophiolite）and most likely connects with the remnants of the Triassic Meliata–Meliac ocean basin（Stampfli and Borel,2002）in the Balkan *** KS ophiolites also continue eastward within the Pontide Belt into the Elekda?ophiolite（e

关键词： Triassic and Liassic Tethyan Oceanic Tracts within the Pontide Belt Along the Southern Margin of Eurasia rock KS Pb Permo Northern Anatolia

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Physiological Age Status of Female Adults and Off-Season Survival of Rice Leaffolder Cnaphalocrocis medinalis in India

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Rice science 2015年第5期22卷 237-244页

作者： Padmavathi CHINTALAPATI Katti GURURAJ Sailaja VALLABUNI Prasad YENUMULAG directorate of Rice research Central research Institute for Dryland Agriculture

Rice leaffolder, Cnaphalocrocis medinalis, is one of the major foliage feeders found in the rice growing regions in India. When the crop was at maturity, numerous adults of rice leaffolder were found in the rice fields though the larval population gradually decreased, and no eggs were found on rice leaves. The population characteristics of C. medinalis were assessed based on the physiological age status of adults at different crop growth stages. Based on egg development within ovarioles, ovariole appearance number and colour of fat bodies, and characteristics of bursa copulatrix, physiological age status of the adults was described, which served as a basis for the determination of age composition. C. medinalis adults were found during the first week of August on rice plants, of which 44% were in Age 0 with immature ovaries, indicating immigrants. However, 28% adults each were at Ages 1-2 with developing ovaries, indicating local breeding population. The carryover and off-season survival of C. medinalis were also studied to determine the contribution of the alternative hosts in the population growth that helped in devising efficient management strategies. Rice was the most preferred host followed by Triticum aestivum, Echinochloa crusgulli and Brachiaria plantaginea. Various routes of the carryover of C. medinalis from season to season were discussed.

关键词： rice leaffolder physiological age carryover off-season survival alternative host ovariole weed

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