Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 60 of 60

Full-Text Articles in Entire DC Network

The Igneous Rock Intrusion Beneath Ambon And Seram Islands, Eastern Indonesia, Basedon The Integration Of Gravity And Magnetic Inversion: Its Implications For Geothermalenergy Resources, Richard Lewerissa, Sismanto Sismanto, Ari Setiawan, Subagyo Pramumijoyo Jan 2020

The Igneous Rock Intrusion Beneath Ambon And Seram Islands, Eastern Indonesia, Basedon The Integration Of Gravity And Magnetic Inversion: Its Implications For Geothermalenergy Resources, Richard Lewerissa, Sismanto Sismanto, Ari Setiawan, Subagyo Pramumijoyo

Turkish Journal of Earth Sciences

Ambon and Seram islands in eastern Indonesia are located in the convergence zone of three major plates, causing this area to have many geothermal manifestations on the surface. A subsurface geological study on Ambon and Seram has been conducted based on the integration of gravity and magnetic inversion modeling to determine the intrusion of igneous rock as a potential source of geothermal energy. The gravity and magnetic inversion utilized gravity and magnetic anomaly data from the World Gravity Map (WGM) and the Earth Magnetic Anomaly Grid (EMAG), as well as the CRUST 1.0 global earth crust model, as the constraints. …


Frequency-Dependent Body-Q And Coda-Q In Karlıova Triple Junction And Its Vicinity,Eastern Turkey, Alper Demi̇rci̇ Jan 2019

Frequency-Dependent Body-Q And Coda-Q In Karlıova Triple Junction And Its Vicinity,Eastern Turkey, Alper Demi̇rci̇

Turkish Journal of Earth Sciences

A dataset obtained from six broadband stations of 111 small- to moderate-sized local events that occurred between 2010 and 2018 was analyzed to reveal the frequency-dependent seismic body (body-Q) and coda (coda-Q) wave attenuation characteristics of three tectonic branches of the Karlıova Triple Junction: the Varto Fault Zone (VFZ), North Anatolian Fault Zone (NAFZ), and East Anatolian Fault Zone. The magnitude range was between 2.8 and 6.1 with shallow (


Miocene Sediment Mineralogy Of The Lower Chelif Basin (Nw Algeria):Implications For Weathering And Provenance, Fatiha Hadji, Abbas Marok, Ali Mokhtar-Samet Jan 2019

Miocene Sediment Mineralogy Of The Lower Chelif Basin (Nw Algeria):Implications For Weathering And Provenance, Fatiha Hadji, Abbas Marok, Ali Mokhtar-Samet

Turkish Journal of Earth Sciences

Mineralogical investigations of clay and nonclay minerals were conducted on the Miocene sediments from three sections of the lower Chelif basin, northern Algeria. Bulk rock analyses of Miocene sediments show that these clastic sediments are dominated by variable mineralogical compositions and concentrations. Quartz is the dominant mineral through the three stratigraphic intervals and calcite (except in the upper layers) and dolomite are lacking in the Messinian deposits. The clay mineralogy is dominated by smectite (24%) and mixed-layer illite-smectite (I-S) (22%) during the Burdigalian-Langhian, illite (36%) and kaolinite (28%) in the Tortonian, and illite (49%) and I-S (20%) in the Messinian …


Reconstructing The Sedimentary Evolution Of The Miocene Aksu Basin Based On Fan Delta Development (Eastern Mediterranean-Turkey), Serkan Üner, Erman Özsayin, Ramazan Kadi̇r Di̇ri̇k, Tahsi̇n Atti̇la Çi̇ner, Mustafa Karabiyikoğlu Jan 2018

Reconstructing The Sedimentary Evolution Of The Miocene Aksu Basin Based On Fan Delta Development (Eastern Mediterranean-Turkey), Serkan Üner, Erman Özsayin, Ramazan Kadi̇r Di̇ri̇k, Tahsi̇n Atti̇la Çi̇ner, Mustafa Karabiyikoğlu

Turkish Journal of Earth Sciences

The Aksu Basin in southern Turkey is dominantly represented by an alluvial fan and five fan deltas (FDs) developed along the tectonically controlled margins of the basin during the Miocene. Four alternating compressional and tensional tectonic phases have influenced the basin since its formation. Strong tectonic movements caused high sedimentation rates and progradation of large debris-flow and mass-flow dominated FDs. Here we describe two FDs (the Karadağ and Kargı FDs) in detail. The Karadağ FD began to develop under the control of a compressional regime and continued the evolution under a tensional regime. The same tensional regime caused the separation …


Resistivity Inversion Of Transversely Isotropic Media, Ertan Pekşen, Türker Yas Jan 2018

Resistivity Inversion Of Transversely Isotropic Media, Ertan Pekşen, Türker Yas

Turkish Journal of Earth Sciences

In this paper, we have suggested a finite difference algorithm for resistivity forward and inverse modeling with electrically anisotropic media in applied geophysics. Electrical anisotropy affects the surface measurement in a fashion that may make interpretation erroneous. This means that the resistivity section obtained by an inversion method that does not incorporate electrical anisotropy gives the wrong subsurface structure. We used a classical multielectrode dataset of a profile for estimating not only horizontal but vertical resistivity as well. Thus, the electrical anisotropy can be calculated. Finally, the finite difference mesh can be corrected by using the estimated anisotropic coefficient. The …


Palaeontological Evidence And Sedimentary Facies In A Lower Miocene (Aquitanian) Succession From The Bingöl Minibasin (Sivas Basin), Central Anatolia, Mehmet Serkan Akki̇raz, Özgen Kangal, Nazi̇re Özgen Erdem, Yeşi̇m Büyükmeri̇ç, Ci̇han Doğruöz Jan 2018

Palaeontological Evidence And Sedimentary Facies In A Lower Miocene (Aquitanian) Succession From The Bingöl Minibasin (Sivas Basin), Central Anatolia, Mehmet Serkan Akki̇raz, Özgen Kangal, Nazi̇re Özgen Erdem, Yeşi̇m Büyükmeri̇ç, Ci̇han Doğruöz

Turkish Journal of Earth Sciences

The results of palaeontological (palynological and mollusc) and sedimentological analyses of the lower Miocene deposits from the Bingöl minibasin, a part of the Sivas Basin, are exhibited to define the vertical shifts in sedimentation environments and plant covers, linking to eustasy. The presence of index species Corbulomya (Lentidium) aquitanica suggests an Aquitanian age for the studied succession, which can be divided into three informal units: a lower unit, a middle unit, and an upper unit. Fine-grained sediments of the lower unit were deposited in a low sea-level setting due to high quantities of terrestrial palynomorphs. This unit is overlain by …


Marine Effects On Vertical Electrical Soundings Along Shorelines, Emi̇n Uğur Ulugergerli̇ Jan 2017

Marine Effects On Vertical Electrical Soundings Along Shorelines, Emi̇n Uğur Ulugergerli̇

Turkish Journal of Earth Sciences

Onshore applications of direct current resistivity (DCR) along shorelines suffer a short-circuit-like phenomenon due to electrical current flowing through a more conductive body of water rather than ground. Our study of the numerical simulation of DCR data with a three-dimensional forward model demonstrated that the apparent resistivity was reduced as a function of the sea depth and the distance of measurement site to the shoreline. Furthermore, it was concluded that the "marine effects" on DCR data (i.e. reduction in apparent resistivity) become nonnegligible as the ratio of half-electrode expansion (AB/2) to the distance to the shoreline is larger than one. …


Paleoenvironment Of The Late Oligocene From The Kağızman-Tuzluca Basin (Northeastern Anatolia) Based On The Micro- And Macrofloras, Mi̇ne Sezgül Kayseri̇ Özer, Recep Hayretti̇n Sancay, Şevket Şen, Koray Sözeri̇, Gregoire Métais, Turhan Ayyildiz, Baki̇ Erdoğan Varol Jan 2017

Paleoenvironment Of The Late Oligocene From The Kağızman-Tuzluca Basin (Northeastern Anatolia) Based On The Micro- And Macrofloras, Mi̇ne Sezgül Kayseri̇ Özer, Recep Hayretti̇n Sancay, Şevket Şen, Koray Sözeri̇, Gregoire Métais, Turhan Ayyildiz, Baki̇ Erdoğan Varol

Turkish Journal of Earth Sciences

The Kağızman-Tuzluca Basin in East Anatolia is still poorly documented for its stratigraphy and in particular its paleofloral assemblages. In this study, the microfloras from the Kağızman-Kötek and Kömürlü areas and the macroflora from the Tuzluca area in this basin have been defined to overcome this deficiency. Sedimentary sequences of the Kağızman-Kömürlü area have been deposited in terrestrial conditions different from the sequences of the Kağızman-Kötek and Tuzluca areas, which were deposited in brackish conditions near a shallow marine environment. Paleovegetation in eastern Anatolia is represented by mixed mesophytic and coniferous forests restricted to high and middle altitudes (e.g. Pinus, …


Quartz-Mica Schist And Gneiss Hosted Clay Deposits Within The Yenipazar(Yozgat, Central Anatolia) Volcanogenic Massive Sulfide Ore, Şih Ali̇ Sayin Jan 2016

Quartz-Mica Schist And Gneiss Hosted Clay Deposits Within The Yenipazar(Yozgat, Central Anatolia) Volcanogenic Massive Sulfide Ore, Şih Ali̇ Sayin

Turkish Journal of Earth Sciences

The Yenipazar deposit of volcanogenic sulfide occurrence, situated approximately 9 km SW of Yenipazar, is hosted in quartz-muscovite schists and gneiss. Following the Late Cretaceous, the quartz-mica schists and gneiss have been altered to clay minerals, resulting in important kaolin deposits. The clay deposits consist mainly of halloysite, kaolinite, smectite, illite, muscovite, chlorite, and α-quartz. Biotite, alunite, jarosite, pyrite, hematite, calcite, low cristobalite, and feldspar are present in minor amounts. In places, some mixed-layer clays, such as kaolinite/smectite and smectite/illite, are also observed within the clay deposits. Barite is present in a few clay samples. α-Quartz is the dominant silica …


Mineral Chemistry Of Igneous Rocks In The Lar Cu-Mo Prospect, Southeastern Part Of Iran: Implications For P, T, And ƒO2, Rahele Moradi, Mohammad Boomeri, Sasan Bagheri, Kazuo Nakashima Jan 2016

Mineral Chemistry Of Igneous Rocks In The Lar Cu-Mo Prospect, Southeastern Part Of Iran: Implications For P, T, And ƒO2, Rahele Moradi, Mohammad Boomeri, Sasan Bagheri, Kazuo Nakashima

Turkish Journal of Earth Sciences

The Lar Cu-Mo prospect is located 20 km north of Zahedan in Sistan and Baluchestan Province. This area is geologically situated in the Sistan Suture Zone. The Cu-Mo mineralization occurs as silicic veins in the Lar igneous rocks and includes hypogene chalcopyrite, bornite, and molybdenite mineralization. The syenite to monzonite host rocks occur as stock and dyke and display granular to porphyritic texture. In this study, mineral chemistry and petrographic examination of igneous rocks are used to constrain the crystallization conditions of the magma. The compositional range of plagioclase is relatively narrow (0.11%-26.05% An), whereas that of potassium feldspar is …


Determining The Main Strand Of The Eskişehir Strike-Slip Fault Zone Using Subsidiary Structures And Seismicity: A Hypothesis Tested By Seismic Reflection Studies, Gürol Seyi̇toğlu, Gali̇p Berkan Ecevi̇toğlu, Bülent Kaypak, Yücel Güney, Muammer Tün, Korhan Esat, Uğur Avdan, Abi̇di̇n Temel, Alper Çabuk, Sevgi̇ Telsi̇z, Güzi̇n Gülsev Uyar Aldaş Jan 2015

Determining The Main Strand Of The Eskişehir Strike-Slip Fault Zone Using Subsidiary Structures And Seismicity: A Hypothesis Tested By Seismic Reflection Studies, Gürol Seyi̇toğlu, Gali̇p Berkan Ecevi̇toğlu, Bülent Kaypak, Yücel Güney, Muammer Tün, Korhan Esat, Uğur Avdan, Abi̇di̇n Temel, Alper Çabuk, Sevgi̇ Telsi̇z, Güzi̇n Gülsev Uyar Aldaş

Turkish Journal of Earth Sciences

The Eskişehir Fault Zone is one of the major neotectonic structures of Turkey, extending from İnegöl (Bursa) to Cihanbeyli (Konya). The fault zone presents a considerable seismic risk for the city of Eskişehir but the exact locations of active segments and the source of the major seismic event, the 1956 earthquake (M = 6.5) that occurred in the instrumental period (from 1900 to 2013), have been debated in recent literature. The structural data obtained from field studies indicate an approximately N60W-trending main strand of the right lateral strike-slip Eskişehir Fault Zone. This trend corresponds to the en echelon bends on …


Bicoelia Corticifera, A New Inozoid Sponge From The Upper Triassic (Norian) Reef Boulders Of The Central Taurids (Southern Turkey), Baba Senowbari-Daryan, Michael Link Jan 2014

Bicoelia Corticifera, A New Inozoid Sponge From The Upper Triassic (Norian) Reef Boulders Of The Central Taurids (Southern Turkey), Baba Senowbari-Daryan, Michael Link

Turkish Journal of Earth Sciences

Upper Triassic Norian reef boulders, exposed in a locality in the Central Taurids, southern Turkey, yielded a high number of hypercalcified sponges, including Sphinctozoans, Inozoans, Spongiomorphids, and Chaetetids. The reef boulders are exposed near the fountain Tavuk Çeşme, located at the road leading from the town of Aksu to Yenişarbademli. Geologically this locality belongs to the Anamas Akseki Autochthon. In this paper a new inozoan sponge, Bicoelia corticifera nov. sp., is described from Tavuk Çeşme. It is a cylindrical and unbranched sponge, found in several thin sections. The sponge is characterized by 2 axial spongocoels, and the sponge wall is …


Neotectonics Of The Zanjan-Kazvin Area, Central Iran: Left Lateral Strike‐Slip Induced Restraining Stepovers, Moosarreza Toori, Gürol Seyi̇toğlu Jan 2014

Neotectonics Of The Zanjan-Kazvin Area, Central Iran: Left Lateral Strike‐Slip Induced Restraining Stepovers, Moosarreza Toori, Gürol Seyi̇toğlu

Turkish Journal of Earth Sciences

The neotectonics of the Zanjan-Kazvin area are dominated by the region-wide E-W trending left lateral strike-slip faults. These faults create restraining and releasing stepovers indicating strain partitioning. Instead of the NW-SE trending long range-parallel continuous thrust faulting suggested in previous studies, this paper demonstrates that there are E-W trending range-crossing left lateral strike-slip faults creating short range-parallel thrust faults in the restraining stepovers. Establishing this strike-slip-induced structural style might contribute to an understanding of the nature of the Elburz (Alborz) Mountains located between the Central Iran and Caspian blocks.


Fluctuations Of Sea Water Temperature Based On Nannofloral Changes During The Middle To Late Miocene, Adana Basin, Turkey, Manolya Sinaci Jan 2013

Fluctuations Of Sea Water Temperature Based On Nannofloral Changes During The Middle To Late Miocene, Adana Basin, Turkey, Manolya Sinaci

Turkish Journal of Earth Sciences

Some nannoplankton species are sensitive to water temperatures. While Coccolithus pelagicus and Reticulofenestra gelida indicate cooler water conditions, the genera Discoaster and Sphenolithus and Calcidiscus leptoporus are indicative of warmer water environments. This paper focuses on relative fluctuation of sea water temperatures during the Middle and Late Miocene, emphasised by cold and warm nannofossil changes in abundance in 2 wells. At the A-1 well in the Middle Miocene, the total abundance of cooler water species is 45%, while that of the warmer species is 3%. During the Late Miocene, the total abundance for cooler water species decreases to 34%; in …


Tectonosedimentary Development And Palaeoenvironmental Changes In The Acıgöl Shallow-Perennial Playa-Lake Basin, Sw Anatolia, Turkey, Cahi̇t Helvaci, Mehmet Ci̇hat Alçi̇çek, İbrahi̇m Gündoğan, Ünsal Gemi̇ci̇ Jan 2013

Tectonosedimentary Development And Palaeoenvironmental Changes In The Acıgöl Shallow-Perennial Playa-Lake Basin, Sw Anatolia, Turkey, Cahi̇t Helvaci, Mehmet Ci̇hat Alçi̇çek, İbrahi̇m Gündoğan, Ünsal Gemi̇ci̇

Turkish Journal of Earth Sciences

The late Cenozoic extensional deformation formed several NE-trending fluvio-lacustrine basins in SW Anatolia, filled by alluvial, fluvial and lacustrine deposits. Among them, the Acıgöl basin , is notable for its tectono-sedimentary development of a prominent shallow-perennial playa-lake setting. The basin initially subsided to receive coarse-clastic alluvial deposits, merging into fluvial systems and central shallow lakes. Subsequent basin deepening with significant sediment supply from surrounding basement horsts caused gradual shrinkage of the relatively small shallow lakes, due to renewed progradation of alluvial fans and they eventually dried out completely. The sedimentation pattern and palaeoenvironmental changes record a constant tectonic, sedimentation, climatic …


Microfacies Correlation Analysis Of The Oligocene-Miocene Asmari Formation, In The Central Part Of The Rag-E-Safid Anticlinal Oil Field, Zagros Basin, South-West Iran, Mahnaz Amirshahkarami Jan 2013

Microfacies Correlation Analysis Of The Oligocene-Miocene Asmari Formation, In The Central Part Of The Rag-E-Safid Anticlinal Oil Field, Zagros Basin, South-West Iran, Mahnaz Amirshahkarami

Turkish Journal of Earth Sciences

The Oligocene-Miocene Asmari Formation was deposited in a carbonate ramp setting at the margin of the Zagros Basin in south-western Iran. The subsurface sedimentary successions of the Asmari Formation have been studied using cores from the Rag-e-Safid oil field, in order to determinate their microfacies and sedimentary palaeoenvironments. Based on texture analysis and faunal assemblages, 10 microfacies types have been recognised and interpreted. They indicate different depositional settings: open marine, oolitic and bioclastic shoal, lagoon, tidal flat and beach. The microfacies have been interpreted as indicative of the inner and middle ramp. In accordance with the temporal and spatial correlation …


Stratigraphy, Sedimentology And Palynology Of The Neogene-Pleistocene(?) Rocks Around Akçaşehir- Tire-İzmir (Küçük Menderes Graben, Western Anatolia), Tahi̇r Emre, Meti̇n Tavlan, Mehmet Serkan Akki̇raz, İsmai̇l İşi̇ntek Jan 2011

Stratigraphy, Sedimentology And Palynology Of The Neogene-Pleistocene(?) Rocks Around Akçaşehir- Tire-İzmir (Küçük Menderes Graben, Western Anatolia), Tahi̇r Emre, Meti̇n Tavlan, Mehmet Serkan Akki̇raz, İsmai̇l İşi̇ntek

Turkish Journal of Earth Sciences

The basement rocks located in the central part of the southern edge of the Küçük Menderes Graben, around Akçaşehir-Tire are composed of marbles, schists, gneisses and metagabbros of the Ödemiş-Kiraz submassif of the Menderes Massif, and schists, marbles and meta-olistostromes of the Cycladic Complex. The basement is unconformably overlain by Neogene-Quaternary continental sediments. These continental basin fills are comprised of the Ayaklıkırı Formation, the Aydoğdu Formation and alluvium that unconformably overlies them. The Lower-Upper Miocene Ayaklıkırı Formation consists of lacustrine and fluvial deposits. The Plio-Pleistocene (?) Aydoğdu Formation is made up of alluvial fan deposits. Vast plains of alluvium cover …


Epidiceras (Bivalvia, Hippuritoidea) From The Tithonian–Berriasian Torinosu-Type Limestones Of The Sakawa Area, Southwest Japan, Shin-Ichi Sano, Peter W. Skelton Jan 2010

Epidiceras (Bivalvia, Hippuritoidea) From The Tithonian–Berriasian Torinosu-Type Limestones Of The Sakawa Area, Southwest Japan, Shin-Ichi Sano, Peter W. Skelton

Turkish Journal of Earth Sciences

Excavated specimens of two primitive rudists, Epidiceras speciosum (Goldfuss) and Epidiceras guirandi (de Loriol), are systematically described for the first time from the Tithonian-Berriasian Torinosu-type limestones of the Torinosu Group in the Sakawa area, Central Shikoku, Southwest Japan. E. guirandi was previously known only from the Late Kimmeridgian Mediterranean Tethys, so this occurrence in Southwest Japan significantly extends the recorded biogeographical and stratigraphical distribution of the species. Moreover, the documentation of E. speciosum from the Torinosu-type limestones in Japan and the Bau Limestone in Sarawak, Borneo, indicate that this species was already widespread throughout the Tethyan Realm at that time. …


Basement Types, Lower Eocene Series, Upper Eocene Olistostromes And The Initiation Of The Southern Thrace Basin, Nw Turkey, Aral İ. Okay, Ercan Özcan, William Cavazza, Ni̇lgün Okay, György Less Jan 2010

Basement Types, Lower Eocene Series, Upper Eocene Olistostromes And The Initiation Of The Southern Thrace Basin, Nw Turkey, Aral İ. Okay, Ercan Özcan, William Cavazza, Ni̇lgün Okay, György Less

Turkish Journal of Earth Sciences

The Eocene sequence of the southern Thrace Basin unconformably overlies two types of basement: (1) Slate, limestone and phyllite crop out in small inliers under the Upper Eocene conglomerates and limestones in the Mecidiye region, north of Saros Bay. These low-grade metamorphic rocks form the eastern extension of the Circum-Rhodope Belt of Greece. (2) In the Şarköy region south of the Ganos Fault, tectonically elevated basement consisting of serpentinite, metadiabase and Upper Cretaceous blueschists is unconformably overlain by the upper Bartonian to lower Priabonian shallow marine limestones of the Soğucak Formation. In some places erosional remnants of an upper Ypresian …


Surface And Subsurface Characteristics Of The Çankırı Basin (Central Anatolia, Turkey): Integration Of Remote Sensing, Seismic Interpretation And Gravity, Nuretdi̇n Kaymakçi, Şenol Özmutlu, Paul M. Van Van Dijk, Yakup Özçeli̇k Jan 2010

Surface And Subsurface Characteristics Of The Çankırı Basin (Central Anatolia, Turkey): Integration Of Remote Sensing, Seismic Interpretation And Gravity, Nuretdi̇n Kaymakçi, Şenol Özmutlu, Paul M. Van Van Dijk, Yakup Özçeli̇k

Turkish Journal of Earth Sciences

The geology of the Çankırı Basin has been studied using multi-source data including satellite images, aerial photos, gravimetric data and seismic sections, which are subsequently used to generate maps and a 3D model of that part of the basin covered by the seismic sections. From the compilation, three different phases of deformation are recognized. The earliest phase is characterized by thrusting during the Early Tertiary. The second deformation phase is characterized by extensional deformation associated with normal faulting in the latest Early Miocene to Middle Miocene. The third, and the last, phase is characterized by compressional deformation manifested by inversion …


Application Of The Normalized Full Gradient (Nfg) Method To Resistivity Data, Ali̇ Aydin Jan 2010

Application Of The Normalized Full Gradient (Nfg) Method To Resistivity Data, Ali̇ Aydin

Turkish Journal of Earth Sciences

This paper proposes the application of the normalized full gradient (NFG) method to resistivity studies and illustrates that the method can greatly reduce the time and work load needed in detecting buried bodies using resistivity measurement. The NFG method calculates resistivity values at desired electrode offsets by extrapolation of a function of resistivity measurements (i.e. the gradient) to other depth levels using resistivity measurements done at one electrode offset only. The performance and reliability of the NFG method is tested on laboratory and field resistivity data from two sites by comparing the trend of the resistivity values at six or …


Ontogeny And Funtional Morphology Of A Lower Cretaceous Carpinid Rudist (Bivalvia, Hippuritoida), Robert W. Scott, Meghan Weaver Jan 2010

Ontogeny And Funtional Morphology Of A Lower Cretaceous Carpinid Rudist (Bivalvia, Hippuritoida), Robert W. Scott, Meghan Weaver

Turkish Journal of Earth Sciences

Caprinuloidea rudists are locally abundant and widespread in Lower Cretaceous (Albian Stage) Edwards Formation in Texas. Landward of the shelf margin on the shallow marine Comanche Shelf rudists built circular and elongate bioherms with coarse-grained flank deposits. Two caprinid morphotypes suggest that some lived as elevators above the substrate and others were recumbent upon mobile grain flats. Elevators have elongated attached valves and weakly coiled free valves and recumbents have arcuate attached valves and strongly coiled free valves. Detailed morphologic studies are not possible on the many molds and casts, but a few specimens are silicified. Their internal structures can …


Oligocene History Of The Çardak - Dazkırı Subbasin (Denizli, Sw Turkey): Integrated Molluscan And Planktonic Foraminiferal Biostratigraphy, Yeşi̇m İslamoğlu, Aynur Hakyemez Jan 2010

Oligocene History Of The Çardak - Dazkırı Subbasin (Denizli, Sw Turkey): Integrated Molluscan And Planktonic Foraminiferal Biostratigraphy, Yeşi̇m İslamoğlu, Aynur Hakyemez

Turkish Journal of Earth Sciences

The detailed analysis of molluscan and planktonic foraminiferal fauna in the Oligocene Çardak-Dazkırı sub-basin, in northeastern Denizli provin ce (western Turkey) allowed accurate dating of the deposits, together with interpretation of their depositional environments. Gastropod, bivalve, scaphopod and planktonic foraminiferal assemblages identified in ten sections reveal a succession which was deposited between the Late Rupelian and Early Chattian. Planktonic foraminifera, documented for the first time in the basin, indicate the P19 Zone (Turborotalia ampliapertura Zone) of the Late Rupelian at the base of the succession whereas Molluscan fauna, determined for the first time in this study, assign the whole succession, …


Geochemistry Of The Middle Miocene Collision-Related Yamadaği ( Eastern Anatolia) Calc-Alkaline Volcanics, Turkey, Taner Eki̇ci̇, Musa Alpaslan, Osman Parlak, Ali̇ Uçurum Jan 2009

Geochemistry Of The Middle Miocene Collision-Related Yamadaği ( Eastern Anatolia) Calc-Alkaline Volcanics, Turkey, Taner Eki̇ci̇, Musa Alpaslan, Osman Parlak, Ali̇ Uçurum

Turkish Journal of Earth Sciences

Major, trace element and K-Ar age determinations are reported for a suite from the Yamadağı volcanics in the Eastern Anatolia. The exposed rocks mainly consist of medium-potassium calc-alkaline basaltic andesites, andesites and dacites. Petrographical data exhibit disequilibrium mineral textures, such as resorption of the ferromagnesian phases, clinopyroxene-mantled orthopyroxene, and sieve-textured plagioclases. The Yamadağı volcanics have a calk-alkaline character, and trace element characteristics exhibit that the volcanics resemble subduction zone volcanics and/or volcanics assimilated by continental crust. K/Ar age determinations show that the Yamadağı volcanics were formed during the 12 ± 0.5 - 15 ± 0.5 Ma time interval. Geochemical characteristics …


In Memoriam Jean Philippe Marcoux, A.M. Celal Şengör Jan 2008

In Memoriam Jean Philippe Marcoux, A.M. Celal Şengör

Turkish Journal of Earth Sciences

No abstract provided.


Reply To Comment On ‘Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing’, Zafer Arslan Jan 2006

Reply To Comment On ‘Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing’, Zafer Arslan

Turkish Journal of Earth Sciences

No abstract provided.


A Proposal For A Method To Establish Natural-Hazard-Based Land-Use Planning: The Adapazarı Case Study, Alper Çabuk Jan 2001

A Proposal For A Method To Establish Natural-Hazard-Based Land-Use Planning: The Adapazarı Case Study, Alper Çabuk

Turkish Journal of Earth Sciences

As a result of recent disasters in northwest Turkey (Marmara earthquake August 17, 1999/Düzce earthquake November 12, 1999), many buildings collapsed and many people experienced physical and mental problems. We can suppose that the problems caused by these earthquakes will be solved in the future, but geological studies show that the problems will not disappear in that many scientists are predicting a new disaster that will affect the same region. A design of natural-hazard land-use planning for minimising the consequences of recent and possible earthquakes is presented herein. The Adapazarı case is used to demonstrate the fundamentals of this study. …


Geology Of The Dereiçi (Şavsat, Artvin) Cu-Pb-Zn Deposits, Mesut Soylu, Ayhan Erler Jan 1999

Geology Of The Dereiçi (Şavsat, Artvin) Cu-Pb-Zn Deposits, Mesut Soylu, Ayhan Erler

Turkish Journal of Earth Sciences

The geological relationships between the rock units in the Dereiçi/Şavsat (Artvin) region and vein-type Cu-Pb-Zn deposits were presented in this paper. The study area comprises the Upper Cretaceous intermediate volcanic rocks and sedimentary rocks, with Post-Eocene dykes of andesitic and diabasic composition. The mineral deposits are classified as (1) Sphalerite-Galena-Chalcopyrite-Pyrite veins (Talatin Madeni, Binektasi and Fikrinin Madeni), (2) milky quartz-Chalcopyrite-Sphalerite-Galena-Pyrite veins and (3) Chalcopyrite-Pyrite veins. The general paragenetic sequence of the mineralizations is observed as quartz I-pyrite-chalcopyrite-sphalerite-galena-quartz II-chalcocite-covellite. The wall rocks are subjected to silicification, sericitic alteration, chloritization and carbonatization.


Geochemistry And Origin Of The Oligocene Binkılıç Manganese Deposit;Thrace Basin, Turkey, Ali Haydar Gülteki̇n Jan 1998

Geochemistry And Origin Of The Oligocene Binkılıç Manganese Deposit;Thrace Basin, Turkey, Ali Haydar Gülteki̇n

Turkish Journal of Earth Sciences

Many Oligocene Manganese deposits are found in the Trace basin, a Tertiary collisional-collapse type basin in the northwestern part of Turkey. All the mineralizations are originally sedimentary type. The most economically important deposits are around Çatalça; of these, the Binkılıç manganese ore occurs conformably within the Oligocene fossiliferous formations, as a stratiform type manganese deposit. The manganese ores at Binkiliç show a continuity along strike and consists of micro-to Cryptocrystalline pyrolusite, psilomelane, radial manganite, cryptomelane, wad, rhodochrosite and dispersed organic matter, calcite, feldspar, clay minerals, and quartz but generally only minor quantities of limonite and goethite. Mn oxides with variable …


Application Of The Correspondence-Type Geostatistical Analysis On Theco, Ni, As, Ag And Au Concentrations Of The Listwaenites Fromserpentinites In The Divrigi And Kuluncak Ophiolitic Mélanges, Ali̇ Uçurum Jan 1998

Application Of The Correspondence-Type Geostatistical Analysis On Theco, Ni, As, Ag And Au Concentrations Of The Listwaenites Fromserpentinites In The Divrigi And Kuluncak Ophiolitic Mélanges, Ali̇ Uçurum

Turkish Journal of Earth Sciences

The main aim of this research was to find out correlation-if there is any-among Co, Ni, As, Ag and Au concentrations in three different listwaenite sampling sets in Divirigi and Hekimhan areas. The low temperature hydrothermal alteration of serpentinite bodies from the Divrigi and Kuluncak ophiolitic mélanges in the Cürek, Divrigi-Sivas, Güvenç and Karakuz areas, Hekimhan-Malatya, has formed two distinct types of listwaenite. Type I, is silica-carbonate listwaenite, which is dominated by silica+calcite+dolomite+ankerite±magnesite. Type II listwaenite bodies are carbonate listwaenite characterized by calcite+dolomite+ankerite ±magnesite, and lack any significant introduced silica. Correspondence-type geostatistical analysis has been thought to be the best …