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Full-Text Articles in Earth Sciences

Cretaceous Pelagic Red Beds And Black Shales (Aptian-Santonian), Nw Turkey: Global Oceanic Anoxic And Oxic Events, İsmai̇l Ömer Yilmaz Jan 2008

Cretaceous Pelagic Red Beds And Black Shales (Aptian-Santonian), Nw Turkey: Global Oceanic Anoxic And Oxic Events, İsmai̇l Ömer Yilmaz

Turkish Journal of Earth Sciences

The study areas located near the towns of Göynük, Mudurnu and Nallıhan in the central northwestern part of Turkey lie on the `Sakarya Continent´, which is one of the tectonic entities of the Cretaceous geology of Turkey. Measured stratigraphic sections comprise the Aptian pelagic carbonates and the overlying Albian-Coniacian turbiditic sequences, which are all capped by a Late Santonian red pelagic succession. Lower and Upper Aptian, Upper Albian and Cenomanian/Turonian marine black shales recognized in the sections are followed by Lower and Upper Aptian, Upper Albian and Turonian marine red beds. The black shales are generally silty, laminated, and include …


The Earthquake Catalogues For Turkey, Onur Tan, M. Cengi̇z Tapirdamaz, Ahmet Yörük Jan 2008

The Earthquake Catalogues For Turkey, Onur Tan, M. Cengi̇z Tapirdamaz, Ahmet Yörük

Turkish Journal of Earth Sciences

The earthquake data from instrumental records in the last 40 years indicate the general seismicity of the earth. However, examining historical records is necessary to understand long-term seismicity. Catalogue studies about historical earthquakes in Turkey are limited. All these catalogues are on printed paper and a digital database has not yet been prepared. On the other hand, there is no common database for the focal mechanism solutions of the recent destructive earthquakes (Mw>=5.5) in the region. The present study aims to prepare two new digital databases for earth scientists so that the earthquake parameters can be reached from a …


Post-Miocene Deformation In The South Of The Galatean Volcanic Province, Nw Of Central Anatolia (Turkey), Bora Rojay, A. Karaca Jan 2008

Post-Miocene Deformation In The South Of The Galatean Volcanic Province, Nw Of Central Anatolia (Turkey), Bora Rojay, A. Karaca

Turkish Journal of Earth Sciences

Central Anatolia, located on the immense Alpine-Himalayan orogenic belt, has a complicated neotectonic evolution, and NE-SW-trending Neogene horsts-graben systems that rejuvenate pre-existing palaeostructures are among the most important structures which help us understand the tectonic evolution of Central Anatolia. Post-Miocene deformational studies were carried out in Miocene-Quaternary sequences situated at the southeastern margin of the Galatean Volcanic Province (NW of Central Anatolia, Turkey) in order to understand the deformational history of Central Anatolia. The structural analyses were based on bedding attitude data and fault plane slip data. Fold analysis in Miocene units gave an asymmetrical fold axis trending 046ºN. Although …


Punctuated Exhumation And Foreland Basin Formation And Infilling In (Circum)-Central Anatolia (Turkey) Associated With The Neo-Tethyan Closure, Durmuş Boztuğ, Haluk Temi̇z, Raymond Jonckheere, Lothar Ratscbacher Jan 2008

Punctuated Exhumation And Foreland Basin Formation And Infilling In (Circum)-Central Anatolia (Turkey) Associated With The Neo-Tethyan Closure, Durmuş Boztuğ, Haluk Temi̇z, Raymond Jonckheere, Lothar Ratscbacher

Turkish Journal of Earth Sciences

Apatite fission-track data indicate that the (circum)-central Anatolian granitoids (CAG) were exhumed during successive shortening phases following continent-continent collisions within the Neo-Tethyan domain in central and east-central Anatolia. The Early to Middle Paleocene exhumation of the CAG is thought to be a consequence of the collision between the Tauride-Anatolide platform (TAP) and the Eurasian plate (EP) following the consumption of the İzmir-Ankara-Erzincan strand of the northern Neo-Tethys. The Oligocene exhumation documented by the data for the Kösedağ pluton in east-central Anatolia is considered to be related to the compression due to continuing convergence between the EP and TAP which seems …


Textural And Compositional Evidence For Magma Mixing In The Evolution Of The Çamlıdere Volcanic Rocks (Galatean Volcanic Province), Central Anatolia, Turkey, Eli̇f Varol, Abi̇di̇n Temel, Alain Gourgaud Jan 2008

Textural And Compositional Evidence For Magma Mixing In The Evolution Of The Çamlıdere Volcanic Rocks (Galatean Volcanic Province), Central Anatolia, Turkey, Eli̇f Varol, Abi̇di̇n Temel, Alain Gourgaud

Turkish Journal of Earth Sciences

The Çamlıdere area, in the Galatean Volcanic Province (Ankara), Turkey, is composed of rhyolitic, andesitic, trachytic, dacitic and locally basaltic rocks. The older volcanic rocks in the studied area are rhyolitic and the younger ones basaltic. The phenocrysts from all the volcanic rocks exhibit some petrographic disequilibrium features such as: (a) coexistence of reversely, normally and oscillatory zoned sieved or unsieved plagioclase in the same rock; (b) wide compositional variation of An% in feldspar phenocrysts; (c) sieved, unsieved, normally and reversely zoned pyroxenes occur together in a single rock; (d) some orthopyroxene phenocrysts are surrounded by clinopyroxene; (e) reaction textures, …


Statistical Earthquake Frequency Analysis For Western Anatolia, Esi̇n Fi̇ruzan Jan 2008

Statistical Earthquake Frequency Analysis For Western Anatolia, Esi̇n Fi̇ruzan

Turkish Journal of Earth Sciences

In order to apply a statistical earthquake frequency analysis to western Anatolia, the area has been restricted within coordinates 36.50º-40º North and 26.00º-30.00º East. Data used in the analysis belong to the instrumental period from 1.1.1900 to 10.11.2006 (Ms ≥ 4.0). The earthquake record was assumed to be representative of longer periods and the possibility of clusters of seismicity or of extreme magnitude events were ignored. The study area has been divided into eight zones with different seismotectonic properties. All computations have been performed for these zones separately. The earthquake magnitude series is termed as the instantaneous peak over the …


Quaternary Calcrete Development In The Mersin Area, Southern Turkey, Muhsi̇n Eren, Selahatti̇n Kadi̇r, Zübeyde Hati̇poğlu, Murat Gül Jan 2008

Quaternary Calcrete Development In The Mersin Area, Southern Turkey, Muhsi̇n Eren, Selahatti̇n Kadi̇r, Zübeyde Hati̇poğlu, Murat Gül

Turkish Journal of Earth Sciences

Quaternary calcretes are widespread in the Mersin area and occur in a variety of forms. Several distinct calcrete profiles are recognized and subdivided into two major groups defined by mature and immature profiles. Mature calcrete profiles comprise a generally isolated calcrete horizon at the base and hard laminated crust at the top with rarely pisolithic crust in the uppermost part. The immature calcrete profiles consist mainly of an isolated calcrete horizon which is rarely overlain by a laminated crust. Calcrete forms show three main stages of development: (i) a mottled or plugged horizon, comprising isolated calcrete forms such as powdery, …


Relative Sea-Level Changes Of The Lower Cretaceous Deposits In The Chotts Area Of Southern Tunisia, Lazzez Marzouk, Mohamed Ben Youssef Jan 2008

Relative Sea-Level Changes Of The Lower Cretaceous Deposits In The Chotts Area Of Southern Tunisia, Lazzez Marzouk, Mohamed Ben Youssef

Turkish Journal of Earth Sciences

A transition facies between evaporate and clay, carbonate and siliciclastic deposits occurs within the Lower Cretaceous of Southern Tunisia. The sedimentary deposits comprise four major transgressive-regressive sedimentary sequences with distinctive sabkha, tidal to shallow carbonate marine platform, and mixed siliciclastic ramp environments. Sedimentation rates, as well as thickness and facies changes were controlled by tectonic, climatic and eustatic factors. Transgression pulses encompassing the whole Late Hauterivian-Barremian, Early Aptian and Late Albian have controlled the basin infill. Evaporate and siliciclastic systems pass gradually to carbonate deposition in the Chotts area. Our sedimentation model helps to decipher the roles of tectonics and, …


The Evolution Of Travertine Masses In The Sivas Area (Central Turkey) And Their Relationships To Active Tectonics, Levent Mesci̇, Hali̇l Gürsoy, Orhan Tatar Jan 2008

The Evolution Of Travertine Masses In The Sivas Area (Central Turkey) And Their Relationships To Active Tectonics, Levent Mesci̇, Hali̇l Gürsoy, Orhan Tatar

Turkish Journal of Earth Sciences

Sıcak Çermik, Delikkaya and Sarıkaya are important travertine fields with active hot springs located 31 km west of Sivas. Based on their morphology, most of the travertines are classified as fissure-ridge travertines. Eroded sheet-type, terraced, and self-built channel types of travertine are also present at a few locations. Faults and fissures formed in the underlying İncesu Formation, and fissures developing in the fissure-ridge travertines are linked to one another. Tectonic deformation forming the fissure-ridge travertines resulted from NE-SW extension associated with a NW-SE compressional regime related to the Central Anatolian Thrust Belt and Sivas Backthrust. U/Th series age dating results …


Petrogenesis Of The Kösedağ Pluton, Suşehri-Ne Sivas, East-Central Pontides, Turkey, Durmuş Boztuğ Jan 2008

Petrogenesis Of The Kösedağ Pluton, Suşehri-Ne Sivas, East-Central Pontides, Turkey, Durmuş Boztuğ

Turkish Journal of Earth Sciences

The Kösedağ syenite crops out as a shallow-seated pluton within the Eocene volcano-sedimentary rocks and is unconformably overlain by Lower Miocene limestones in the Suşehri-NE Sivas region, east-central Pontides. It consists of syenites and quartz syenites with a phaneritic, porphyritic texture characterized by K-feldspar megacrysts set in a coarse- to medium-grained groundmass comprising K-feldspar, plagioclase, clinopyroxene, amphibole, biotite and quartz. Major element geochemistry data reveal a high-K, alkaline, metaluminous to slightly peraluminous character, with a low Aluminum Saturation Index (ASI) value. The main solidification process, which modified the composition of magma during crystallization, was fractional crystallization, in which syenites solidified …


Palynostratigraphic, Palaeovegetational And Palaeoclimatic Investigations On The Miocene Deposits In Central Anatolia (Çorum Region And Sivas Basin), Mi̇ne Sezgül Kayseri̇, Funda Akgün Jan 2008

Palynostratigraphic, Palaeovegetational And Palaeoclimatic Investigations On The Miocene Deposits In Central Anatolia (Çorum Region And Sivas Basin), Mi̇ne Sezgül Kayseri̇, Funda Akgün

Turkish Journal of Earth Sciences

Palynostratigraphy of the Neogene coal-bearing sediments in the Çorum region and Sivas Basin has been determined, and three sporomorph associations have been defined. Sporomorph association A is described from the Samsun-Havza region and is of latest Burdigalian age. Sporomorph association B is described from the Çorum region and Sivas Basin and is of early-middle Serravalian age. Sporomorph association C is described from the Sivas-Vasıltepe region and is of earliest Tortonian age. Sporomorph association A indicates warm subtropical climatic conditions and the Coexistence Approach (CA) results are: mean annual temperature (MAT) 19 °C, mean annual coldest month (CMT) 9.75 °C, mean …


Platinum-Group Minerals (Pgm) And Other Solid Inclusions In The Elbistan-Kahramanmaraş Mantle-Hosted Ophiolitic Chromitites, South-Eastern Turkey: Their Petrogenetic Significance, İbrahi̇m Uysal Jan 2008

Platinum-Group Minerals (Pgm) And Other Solid Inclusions In The Elbistan-Kahramanmaraş Mantle-Hosted Ophiolitic Chromitites, South-Eastern Turkey: Their Petrogenetic Significance, İbrahi̇m Uysal

Turkish Journal of Earth Sciences

The Elbistan-Kahramanmaraş podiform ophiolitic chromitites, in southeastern Turkey, contain abundant primary inclusions of platinum-group minerals (PGM), base-metals sulphides (BMS) and silicates. These inclusions are very small, generally less than 15 microns in size, and mostly occur in chromian spinel. The following PGM have been recognized: laurite, iridium, irarsite, ruarsite and several unidentified PGE phases. Millerite, pentlandite, bornite, digenite, chalcopyrite and betekhtinite are the BMS that have been identified. Mg-rich hornblende, accompanied by rare olivine, clinopyroxene and phlogopite, are the most abundant silicate inclusions. Most of the PGM, BMS and silicate inclusions are considered primary, i.e. formed during the high temperature …


Palaeoecology Of Coal-Bearing Eocene Sediments In Central Anatolia (Turkey) Based On Quantitative Palynological Data, M. Serkan Akki̇raz, Mi̇ne Sezgül Kayseri̇, Funda Akgün Jan 2008

Palaeoecology Of Coal-Bearing Eocene Sediments In Central Anatolia (Turkey) Based On Quantitative Palynological Data, M. Serkan Akki̇raz, Mi̇ne Sezgül Kayseri̇, Funda Akgün

Turkish Journal of Earth Sciences

In this study, the lignite-bearing Yoncalı formation between Yozgat and Sorgun, in central Anatolia has been palynologically examined. Based on 37 outcrop samples, quantitative palynological studies recognized 64 genera and 136 palynoflora species in the palynological assemblage, which indicated a Middle-?Late Eocene age. This paper also presents a quantitative palaeovegetation and palaeoclimate reconstruction for the Middle-?Upper Eocene coal occurrences of Central Anatolia on the basis of palynomorph assemblages. The diversified floral and ecological characteristics of the pollen taxa indicates that the Middle-?Upper Eocene formations in central Anatolia were characterized by the presence of a complex mangrove swamp with contributions by …


Detailed Geochemistry And K-Ar Geochronology Of The Metamorphic Sole Rocks And Their Mafic Dykes From The Mersin Ophiolite, Southern Turkey, Ömer Faruk Çeli̇k Jan 2008

Detailed Geochemistry And K-Ar Geochronology Of The Metamorphic Sole Rocks And Their Mafic Dykes From The Mersin Ophiolite, Southern Turkey, Ömer Faruk Çeli̇k

Turkish Journal of Earth Sciences

The metamorphic sole rocks at the base of mantle peridotites from the Mersin ophiolite consist of amphibolites and metasedimentary lithologies. Mineral parageneses in the metamorphic sole rocks exhibit amphibolite and greenschist facies assemblages. Geothermobarometric studies based on mineral assemblages and chemical compositions of minerals indicate that average metamorphic temperature during the metamorphism was 522 ± 15 °C and the pressure was less than 5 kb. Amphibolites from the metamorphic sole rocks exhibit geochemical characteristics of a supra-subduction zone (SSZ) type ophiolite, based on their major, trace and rare earth element (REE) compositions. The Th/Nb ratios of the amphibolites are higher …


On The Origin And Age Of The Arıburnu Beachrock, Gelibolu Peninsula, Turkey, Ahmet Evren Ergi̇nal, Nafi̇ye Kiyak Güneç, Mustafa Bozcu, Ahmet Ertek, Hakan Güngüneş, Ali̇ Sungur, Gülen Türker Jan 2008

On The Origin And Age Of The Arıburnu Beachrock, Gelibolu Peninsula, Turkey, Ahmet Evren Ergi̇nal, Nafi̇ye Kiyak Güneç, Mustafa Bozcu, Ahmet Ertek, Hakan Güngüneş, Ali̇ Sungur, Gülen Türker

Turkish Journal of Earth Sciences

The beachrock formation on the Arıburnu coast situated in the Gelibolu Peninsula has been studied by field observation, thin-section interpretation, physicochemical analyses including ICP-AES and SEM/EDS, and OSL dating. These analyses reveal the presence of different amounts of major (Si, Ca, Mg, K, Fe, Al and Na) and trace elements within the beachrock cement with Si (36.2%) and Ca (32.68%) dominating the overall composition. Beachrocks composed of highly-fractured and friable beds reach a total thickness of 80 cm extending from +60 cm at the uppermost level down to -1 m at their most seaward extent and grade from conglomerate to …


Trace Fossils Of The Upper Eocene-Lower Oligocene Transition Of The Manipur, Indo-Myanmar Ranges (Northeast India), Rajkumar Hemanta Singh, Francisco J. Rodriguez Tovar, Soibam Ibotombi Jan 2008

Trace Fossils Of The Upper Eocene-Lower Oligocene Transition Of The Manipur, Indo-Myanmar Ranges (Northeast India), Rajkumar Hemanta Singh, Francisco J. Rodriguez Tovar, Soibam Ibotombi

Turkish Journal of Earth Sciences

A detailed ichnological analysis, for the first time, has been preformed on Upper Eocene-Lower Oligocene Transition of Manipur, Indo-Myanmar Ranges (Northeast India). Previous trace fossil analyses in India are scarce and usually poorly detailed, especially with respect to Cenozoic materials. Sediments from the Disang and Barail groups contain a relatively abundant and moderately diverse trace fossil assemblage that has been characterized at the ichnogenus and ichnospecies level. ?Arenicolites Salter 1857, Helminthopsis tenuis Ksiazkiewicz 1968, Ophiomorpha nodosa Lundgren 1891, Phycodes palmatus (Hall 1852), Planolites montanus Richter 1937, Rhizocorallium jenense Zenker 1836, Thalassinoides paradoxicus (Woodward 1830) and Skolithos linearis (Haldeman 1840) have …


Different Modes Of Stress Transfer In A Strike-Slip Fault Zone: An Example From The North Anatolian Fault System In Turkey, Osman Bektaş, Yener Eyüboğlu, Nafi̇z Maden Jan 2007

Different Modes Of Stress Transfer In A Strike-Slip Fault Zone: An Example From The North Anatolian Fault System In Turkey, Osman Bektaş, Yener Eyüboğlu, Nafi̇z Maden

Turkish Journal of Earth Sciences

The dextral North Anatolian Fault System (NAFS) extends for well over 1000 km from the compressive tectonic domain of eastern Anatolia into the broad and diverse tectonic domain of the western Anatolian, Marmara and Aegean regions. These different tectonic regimes are characterized by a narrow deformation zone in the east and a much broader deformation zone with multiple sub-parallel fault zones in the west. The spatial and temporal distribution of large historical and modern earthquakes (Mw>5) shows two distinctive macro-seismic zones in the eastern and western parts of the NAFS. The eastern macro-seismic zone, between the towns of Erzincan …


Constraints On The Origin Of The Balıkesir Thermal Waters (Turkey) From Stable Isotope (\Delta^{18}O, \Deltad, \Delta^{13}C, \Delta^{34}S) And Major-Trace Element Compositions, Hali̇m Mutlu Jan 2007

Constraints On The Origin Of The Balıkesir Thermal Waters (Turkey) From Stable Isotope (\Delta^{18}O, \Deltad, \Delta^{13}C, \Delta^{34}S) And Major-Trace Element Compositions, Hali̇m Mutlu

Turkish Journal of Earth Sciences

The Balıkesir thermal waters in northwestern Turkey have discharge temperatures in the range of 31.8-98.5 ºC, near neutral pH values of 6.40 to 8.40 and TDS contents between 327 and 2578 mg/l. Samples display variable chemical compositions changing from high-temperature Na_2SO_4-NaHCO_3 waters to warmer CaHCO_3 waters. Trace element concentrations of the waters show significant variation. Comparison between the concentrations of alkaline earth metals in waters and carbonate deposits reveals mobile behavior for Mg and Ba. The ratio of strontium to calcium concentrations in solid and liquid phases was found to be almost the same. Li/Cs and B/Cl ratios of waters …


Stream Sediment Geochemical Exploration For Gold In The Kazdağ Dome In The Biga Peninsula, Western Turkey, Hüseyi̇n Yilmaz Jan 2007

Stream Sediment Geochemical Exploration For Gold In The Kazdağ Dome In The Biga Peninsula, Western Turkey, Hüseyi̇n Yilmaz

Turkish Journal of Earth Sciences

The Tuztaşı Au-Ag mineralized system was discovered within the Kazdağ dome using BLEG (bulk leach extractable gold) and 180-µm stream sediment geochemical data collected across the Biga Peninsula in western Turkey. The deposit is located within the hinge of an antiform consisting mainly of high-grade metamorphic and mélange rocks that include the Altınoluk Pb-Zn-Cu-Ag-Au and Evciler Fe-Au-Cu deposits on the southern and on the northern flanks, respectively; no mineralization has been reported prior to this work which was first carried out in 1996 between Altınoluk and Evciler. The BLEG Ag/Au ratios at Tuztaşı (max 87) and Altınoluk (max 43) are …


Sulfur And Lead Isotope Investigations Of The Carbonate-Hosted Pb-Zn Deposits In The Yahyalı Region, Kayseri, Southern Turkey, Osman Koptagel, Ulvi̇ Ulusoy, Anthony E. Fallick Jan 2007

Sulfur And Lead Isotope Investigations Of The Carbonate-Hosted Pb-Zn Deposits In The Yahyalı Region, Kayseri, Southern Turkey, Osman Koptagel, Ulvi̇ Ulusoy, Anthony E. Fallick

Turkish Journal of Earth Sciences

Carbonate-hosted Pb-Zn deposits are common in the Yahyalı region (Taurus Belt) with galena the most abundant sulfide mineral. The mean d34S values for Göynük, Celaldağı Desandre, Demircilik, Tekke, Havadan and Suçatı deposits were +0.2±0.5, +9.3±0.8, +10.7±1.3, +10.8±1.3, +11.5±2.4, -4.2±0.4%o, respectively. The mean 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb measurements for the studied deposits were 18.968±0.005, 15.741±0.005 and 39.074±0.016 for Göynük, 18.702±0.006, 15.715±0.006 and 38.883±0.021 for Celaldağı Desandre, 18.618±0.020, 15.727±0.008 and 38.852±0.032 for Demircilik, 18.808±0.017, 15.751±0.028 and 38.983±0.166 for Suçatı. The sulfur isotope systematics imply that sulfur originated from a mixture of different sources for the Göynük and Suçatı deposits, but was probably …


Effects Of Compaction Parameters On Heavy Metal Mass Transport In Ankara Clay Liner: Experimental Approach, M. Zeki̇ Çamur, Füsun Canpolat, Hasan Yazicigi̇l Jan 2007

Effects Of Compaction Parameters On Heavy Metal Mass Transport In Ankara Clay Liner: Experimental Approach, M. Zeki̇ Çamur, Füsun Canpolat, Hasan Yazicigi̇l

Turkish Journal of Earth Sciences

Mass transports of Cl, Cd, Cr, Cu, Fe, K, Mn, Ni, Pb and Zn ions through the Ankara clay liner was prepared under two different compaction conditions, and were studied experimentally on the bases of sorption and hydrodynamic dispersion processes. According to geotechnical tests, the Ankara clay material is highly plastic, inorganic clay having a liquid limit of 73, a plastic limit of 29 and a plasticity index of 44. Optimum compaction of the material requires 32% water content and 1.413 g/cm^3 dry density. Two materials, prepared using half of the optimum water content but optimum energy conditions (I) and …


A Mineralogical Note On Boulangerite, Geocronite And Yenerite From Near Işık Dağı (Kızılcahamam-Ankara), Turkey, W. E. Sharp, Mark Wieland, Steven K. Mittwede Jan 2007

A Mineralogical Note On Boulangerite, Geocronite And Yenerite From Near Işık Dağı (Kızılcahamam-Ankara), Turkey, W. E. Sharp, Mark Wieland, Steven K. Mittwede

Turkish Journal of Earth Sciences

Microprobe studies have facilitated recognition of the first documented occurrence of geocronite from Işık Dağı (Ankara, Turkey). While yenerite remains a discredited species along the PbS-Sb2S3 compositional join, our analyses show significant arsenic as did the original analyses for yenerite; thus, this name might be retained for arsenic-bearing varieties of boulangerite.


Stratigraphy And Geochemical Features Of The Early Miocene Bimodal (Ultrapotassic And Calc-Alkaline) Volcanic Activity Within The Ne-Trending Selendi Basin, Western Anatolia, Turkey, Yalçin Ersoy, Cahi̇t Helvaci Jan 2007

Stratigraphy And Geochemical Features Of The Early Miocene Bimodal (Ultrapotassic And Calc-Alkaline) Volcanic Activity Within The Ne-Trending Selendi Basin, Western Anatolia, Turkey, Yalçin Ersoy, Cahi̇t Helvaci

Turkish Journal of Earth Sciences

Western Anatolia has experienced thickening and orogenic collapse subsequent to the Eocene continent-arc collision. The early stage of the post-collisional volcanism in the region was thought to have produced widespread lavas and pyroclastic deposits of calc-alkaline basaltic andesite to rhyolite composition. However, in the Selendi Basin, one of the NE-trending basins in western Anatolia, there are two distinct volcanic unit compositions associated with the Lower Miocene sedimentary rocks: (1) a calc-alkaline, high-potassic felsic unit; and (2) alkaline, ultrapotassic lamproitic units, i.e. both are bimodal in character. The calc-alkaline felsic volcanic rocks (Eğreltidağ volcanic unit) are composed of wide-spread pyroclastic rocks …


Nature, Provenance And Relationships Of Early Miocene Palaeovalley Fills, Northern Adana Basin, Turkey: Their Significance For Sediment-Bypassing On A Carbonate Shelf, A. Sami̇ Derman, Kemal Gürbüz Jan 2007

Nature, Provenance And Relationships Of Early Miocene Palaeovalley Fills, Northern Adana Basin, Turkey: Their Significance For Sediment-Bypassing On A Carbonate Shelf, A. Sami̇ Derman, Kemal Gürbüz

Turkish Journal of Earth Sciences

The Gildirli Formation is the oldest Neogene rock unit in the Adana Basin and was formed prior to the regionally extensive Early Miocene marine transgression. These coarse clastic red-beds provide important evidence about the causes and early phases of filling in this large trough, because the Gildirli Formation sediments fill an irregular palaeotopography carved out of Palaeozoic and Mesozoic basement rocks. Detailed study of the Gildirli Formation reveals the existence of at least two alluvial fans supplied from different source areas. A northeastern fan, exposed around Gildirli Village, was fed by streams draining an area of ophiolitic mélange, Mesozoic and …


Strontium Isotopic And Micropalaeontological Dating Used To Help Redefine The Stratigraphy Of The Neotectonic Hatay Graben, Southern Turkey, Sarah J. Boulton, Alastair H. F. Robertson, Robert M. Ellam, Ümi̇t Şafak, Ulvi̇ Can Ünlügenç Jan 2007

Strontium Isotopic And Micropalaeontological Dating Used To Help Redefine The Stratigraphy Of The Neotectonic Hatay Graben, Southern Turkey, Sarah J. Boulton, Alastair H. F. Robertson, Robert M. Ellam, Ümi̇t Şafak, Ulvi̇ Can Ünlügenç

Turkish Journal of Earth Sciences

In this paper we report for the Hatay Graben, new micropalaeotology, the first strontium dating and new sedimentology. The previous lack of a modern systematic stratigraphy was problematic for the study of the Hatay region. With the new data combined with the existing literature we evaluate and redefine the lithostratigraphy following international standards. The focus of this paper is on the Neogene cover rocks that record the transition from a regional carbonate shelf environment during Palaeocene to Eocene times, through late-stage continental collision, to recent continental rift tectonics that were initiated in the Middle Miocene and continue to operate to …


Pharyngeal Teeth, Lateral Ethmoids, And Jaw Teeth Of Fishes And Additional Fossils From The Late Miocene (Late Khersonian / Early Maeotian) Of Eastern Paratethys (Yalova, Near İstanbul, Turkey), Neri̇man Rühkert Ülkümen, Erdi̇nç Yi̇ği̇tbaş Jan 2007

Pharyngeal Teeth, Lateral Ethmoids, And Jaw Teeth Of Fishes And Additional Fossils From The Late Miocene (Late Khersonian / Early Maeotian) Of Eastern Paratethys (Yalova, Near İstanbul, Turkey), Neri̇man Rühkert Ülkümen, Erdi̇nç Yi̇ği̇tbaş

Turkish Journal of Earth Sciences

A late Khersonian to early Maeotian fossil assemblage from the Upper Miocene to Lower Pliocene Yalakdere Formation near Yalova city (northwestern Anatolia, Turkey) is documented. The following fish taxa, represented by pharyngeal teeth, lateral ethmoids and jaw teeth are described: Cyprinidae with Carassius sp., Tinca sp., Scardinius sp., Leuciscus sp., Barbus sp., Cobitidae with Cobitis sp., Siluridae with Silurus sp., and Esocidae with Esox sp.. Further described vertebrates are reptiles (Trionyx sp.) and small mammals (cf. Eliomys intermedius FRIANT). Additional invertebrate fauna and flora, comprising diverse gastropods, ostracods, charophytes, pollen and limnic green algae, are listed. The fossil assemblage from …


Late Visean–Early Namurian Bivalves From The Zonguldak Coal Basin, Northwestern Turkey, Yavuz Okan, İzzet Hoşgör Jan 2007

Late Visean–Early Namurian Bivalves From The Zonguldak Coal Basin, Northwestern Turkey, Yavuz Okan, İzzet Hoşgör

Turkish Journal of Earth Sciences

Marine bivalves Septimyalina sublamellosa (Etheridge 1878), Septimyalina lamellosa (de Koninck 1842), Septimyalina minor (Brown 1841) and Posidonia becheri Bronn, 1828 are described from the Visean-Namurian transition of Zonguldak coal basin, Northwestern Turkey. Macroinvertebrate fossils are rare in the Lower Carboniferous of the Zonguldak coal basin and only a few shallow marine forms of Myalinidae and Posidoniidae families are present. Their palaeobiogeographic distribution delineates a seaway from Britain to the Black Sea coast during the Carboniferous.


A Condensed Mesozoic Succession North Of İzmir: A Fragment Of The Anatolide-Tauride Platform In The Bornova Flysch Zone, Aral İ. Okay, Demi̇r Altiner Jan 2007

A Condensed Mesozoic Succession North Of İzmir: A Fragment Of The Anatolide-Tauride Platform In The Bornova Flysch Zone, Aral İ. Okay, Demi̇r Altiner

Turkish Journal of Earth Sciences

The Bornova Flysch Zone consists of large blocks of Mesozoic limestone, basalt, serpentinite and radiolarian chert in a highly sheared clastic matrix of latest Cretaceous to Paleocene age. We describe a condensed Mesozoic section from a limestone block near the village of Urbut, 27 km southwest of Bigadiç, north of İzmir. The section, 81 m thick, starts with massive, thickly-bedded Upper Triassic carbonates with megalodonts and foraminifera characteristic of Late Norian-Rhaetian. These are unconformably overlain by condensed, hemipelagic Tithonian-Middle Albian limestones, 19 m thick, with gaps in the succession. The condensed sequence is, in turn, unconformably overlain by red, pink …


Late Ypresian To Middle Lutetian Orthophragminid Record From Central And Northern Turkey: Taxonomy And Remarks On Zonal Scheme, Ercan Özcan, György Less, Botond Kertesz Jan 2007

Late Ypresian To Middle Lutetian Orthophragminid Record From Central And Northern Turkey: Taxonomy And Remarks On Zonal Scheme, Ercan Özcan, György Less, Botond Kertesz

Turkish Journal of Earth Sciences

Orthophragmines are one of the commonest larger foraminifera in the late Paleocene-Eocene shallow-marine deposits of Turkey. Following several common lineages, such as Discocyclina archiaci, Orbitoclypeus schopeni and O. multiplicatus, a major turnover in the orthophragminid composition - both in diversity and abundance - is observed to occur around the early-late Ypresian boundary. This is manifested in the first appearance/dominance of such important lineages like Discocyclina augustae, D. fortisi, Nemkovella strophiolata, Orbitoclypeus douvillei, O. varians, O. furcatus, Asterocyclina stellata and A. alticostata simultaneously with the disappearance of O. multiplicatus and other forms. These and their successors, ranging up at least to …


Lake Hazar Basin: A Negative Flower Structure On The East Anatolian Fault System (Eafs), Se Turkey, Ercan Aksoy, Murat İnceöz, Ali̇ Koçyi̇ği̇t Jan 2007

Lake Hazar Basin: A Negative Flower Structure On The East Anatolian Fault System (Eafs), Se Turkey, Ercan Aksoy, Murat İnceöz, Ali̇ Koçyi̇ği̇t

Turkish Journal of Earth Sciences

The East Anatolian Fault System (EAFS) is a 30-km-wide, 700-km-long and NE-trending sinistral strike-slip megashear belt between the Anatolian platelet in the northwest and African-Arabian plates in the southeast. It is located between Karlıova County in the NE and Karataş (Adana)-Samandağ (Antakya) in the SW. In the Lake Hazar region, the EAFS consists of five fault zones. These are, from north to south, the Elazığ fault zone, the Uluova fault zone, the Sivrice fault zone, the Adıyaman fault zone and the Lice-Çermik fault zone; in previous studies only the Sivrice fault zone has been reported to be part of the …