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Full-Text Articles in Physical Sciences and Mathematics

The Gümüldür Fire Opal: Mode Of Occurrence And Mineralogical Aspects, Zeki̇ye Karacik, Şengül Can Genç, Recep Fahri̇ Esenli̇, Gülteki̇n Göller Jan 2011

The Gümüldür Fire Opal: Mode Of Occurrence And Mineralogical Aspects, Zeki̇ye Karacik, Şengül Can Genç, Recep Fahri̇ Esenli̇, Gülteki̇n Göller

Turkish Journal of Earth Sciences

Five types of silica polymorphs have been identified in dacitic volcanics from the Gümüldür region of western Anatolia, Turkey. Two of them are micro-quartz and disordered cristobalite (opal-C) that occur within the groundmass of the dacitic volcanic rocks. The others are pore-filling opal nodules including mainly massy opal-CT (opal-CTM) and rarely lussatite (opal-CTL) and amorphous opal (opal-A). Red and orange opal nodules are very similar to the gemologically well-known fire opals. Results of structural, chemical and thermal studies of the Gümüldür opals reveal their origin and mode of occurrence. Opal-CTM has gel-like or nano-grain texture and opal-CTL has a fibrous, …


The Role Of The Palaeogene Adriatic Carbonate Platform In The Spatial Distribution Of Alveolinids, Katica Drobne, Vlasta Cosovic, Alan Moro, Damir Buckovic Jan 2011

The Role Of The Palaeogene Adriatic Carbonate Platform In The Spatial Distribution Of Alveolinids, Katica Drobne, Vlasta Cosovic, Alan Moro, Damir Buckovic

Turkish Journal of Earth Sciences

Sediments of the Palaeogene Adriatic carbonate platform, a distinctive palaeogeographic unit, are today exposed along the eastern Adriatic coast for a distance of 800 km and a width of 100-130 km. The large number of identified alveolinid species (69) from the Early Ypresian (Ilerdian) to the Bartonian record the dynamics of their evolution, with emphasis on the following: (1) great species diversity and great abundance in the middle Ilerdian (SBZ 7-8) followed by a sharp decline in occurrences at the Ilerdian/Cuisian transition; (2) a diversity boom in the late Ypresian (late Cuisian, SBZ 11-12) and (3) an abrupt decrease in …


Faulting And Stress Distribution In The Bolu Pull-Apart Basin (North Anatolian Fault Zone, Turkey): The Significance Of New Dates Obtained From The Basin Fill, Ergun Gökten, Ramazan Demi̇rtaş, Volkan Özaksoy, Erdal Herece, Baki̇ Varol, Uğur Temi̇z Jan 2011

Faulting And Stress Distribution In The Bolu Pull-Apart Basin (North Anatolian Fault Zone, Turkey): The Significance Of New Dates Obtained From The Basin Fill, Ergun Gökten, Ramazan Demi̇rtaş, Volkan Özaksoy, Erdal Herece, Baki̇ Varol, Uğur Temi̇z

Turkish Journal of Earth Sciences

The Bolu Basin in northwestern Turkey, situated in the western part of the North Anatolian Fault Zone (NAFZ), displays the neotectonic features of a pull apart basin. The long axis of the basin extends east-west, parallel to the fault zone and Bolu city, situated in the central part of this basin, was extensively damaged during the 17 August 1999 M= 7.4 and 12 November 1999 M= 7.2 earthquakes. The master strand of the North Anatolian Fault Zone cuts through the basin close to its southern edge and movement on this strand has caused tilting of the basin floor towards the …


Geology And Correlation Of The Mersin Mélanges, Southern Turkey, Patrice Moix, Laurent Beccaletto, Olivier Masset, Heinz W. Kozur, Paulian Dumitrica, Daniel Vachard, Rossana Martini, Gerard Stampfli Jan 2011

Geology And Correlation Of The Mersin Mélanges, Southern Turkey, Patrice Moix, Laurent Beccaletto, Olivier Masset, Heinz W. Kozur, Paulian Dumitrica, Daniel Vachard, Rossana Martini, Gerard Stampfli

Turkish Journal of Earth Sciences

Our paper aims to give a thorough description of the infra-ophiolitic mélanges associated with the Mersin ophiolite. We propose new regional correlations of the Mersin mélanges with other mélange-like units or similar series, located both in southern Turkey and adjacent regions. The palaeotectonic implications of the correlations are also discussed. The main results may be summarized as follows: the infra-ophiolitic mélange is subdivided into two units, the Upper Cretaceous Sorgun ophiolitic mélange and the Ladinian-Carnian Hacialanı mélange. The Mersin mélanges, together with the Antalya and Mamonia domains, are represented by a series of exotic units now found south of the …


Late-Medieval Plagioclase-Titanaugite-Bearing Iron Slags Of The Yapraklı Area (Çankırı), Turkey, W. E. Sharp, Steven K. Mittwede Jan 2011

Late-Medieval Plagioclase-Titanaugite-Bearing Iron Slags Of The Yapraklı Area (Çankırı), Turkey, W. E. Sharp, Steven K. Mittwede

Turkish Journal of Earth Sciences

A mineralogical, mineral-geochemical and ^1^4C geochronological study of slags, previously identified as copper slags, in the Yapraklı area (Çankırı Province) of central Anatolia, has demonstrated that these are late-medieval iron slags consisting mainly of fayalite, glass, plagioclase, titanaugite, ulvöspinel and metallic iron. Because of the high lime content, relative to other medieval and Roman slags, these slags are quite anomalous in their lack of both modal and normative wüstite. Further study of these sites could shed light on the mining history and smelting methods of central Anatolia during a relatively obscure period of major socio-ethnic transition.


Pre-Jurassic Basement Of The Greater Caucasus: Brief Overview, Mark L. Somin Jan 2011

Pre-Jurassic Basement Of The Greater Caucasus: Brief Overview, Mark L. Somin

Turkish Journal of Earth Sciences

The main units of the Greater Caucasus pre-Jurassic basement are represented by Svanetian and North-Caucasian domains brought together tectonically. The former includes continuous Devonian to Upper Triassic marine sequence devoid of any manifestation of Variscan orogenic activity. In contrast, within the limits of the North-Caucasian domain the Variscan events are expressed in classical form. This domain is very heterogeneous and contains both metamorphosed and unmetamorphosed formations. Till recently the former was considered by most authors to be mainly Proterozoic. New geochronological data indicate that the predominant part of these complexes is Palaeozoic in their protolith age. Lithology, P/T conditions of …


Upper Jurassic Reefs From The Russian Western Caucasus: Implications For The Eastern Black Sea, Li Guo, Stephen J. Vincent, Vladimir Lavrishchev Jan 2011

Upper Jurassic Reefs From The Russian Western Caucasus: Implications For The Eastern Black Sea, Li Guo, Stephen J. Vincent, Vladimir Lavrishchev

Turkish Journal of Earth Sciences

Exposures of Upper Jurassic reef outcrops in the Russian western Caucasus provide excellent field analogues for possible reef-complex reservoir targets imaged on seismic reflection data from the northern Shatskiy Ridge, eastern Black Sea. The reefs at outcrop can be generally grouped into coral-dominated, siliceous sponge-microbialite and microbialite types. Coral-dominated reefs occur as isolated patchy and massive forms, and can be subdivided into higher-diversity and low-diversity types. The former developed at shallow-water platform margins and in platform interiors, whilst the latter occurred in deeper-water mid-shelf settings. Siliceous sponge-microbialite and microbialite reefs occur as lenses and mounds that were restricted to deeper-water …


Growth Rate Biometric Quantification By X-Ray Microtomography On Larger Benthic Foraminifera: Three-Dimensional Measurements Push Nummulitids Into The Fourth Dimension, Antonino Briguglio, Brian Metscher, Johann Hohenegger Jan 2011

Growth Rate Biometric Quantification By X-Ray Microtomography On Larger Benthic Foraminifera: Three-Dimensional Measurements Push Nummulitids Into The Fourth Dimension, Antonino Briguglio, Brian Metscher, Johann Hohenegger

Turkish Journal of Earth Sciences

This work demonstrates the potential of three-dimensional biometric quantification using microtomography on larger benthic foraminifera. We compare traditional linear and area measures used for calculating three-dimensional characters with actual 3D measurements made from volume images obtained using X-ray microtomography (microCT). Two specimens of recent larger benthic foraminifera, i.e., Palaeonummulites venosus and Operculina ammonoides, were imaged with a high-resolution microCT scanner. This method enables three-dimensional imaging and calculation of measurements like 3D distances, surfaces and volumes. The quantitative high-resolution images enabled the extraction of the lumina from the proloculus to the last complete scanned chamber and of the canal system spreading …


Different Degrees Of Partial Melting Of The Enriched Mantle Source For Plio−Quaternary Basic Volcanism, Toprakkale (Osmaniye) Region, Southern Turkey, Utku Bağci, Musa Alpaslan, Robert Frei, Mehmet Ali̇ Kurt, Abi̇di̇n Temel Jan 2011

Different Degrees Of Partial Melting Of The Enriched Mantle Source For Plio−Quaternary Basic Volcanism, Toprakkale (Osmaniye) Region, Southern Turkey, Utku Bağci, Musa Alpaslan, Robert Frei, Mehmet Ali̇ Kurt, Abi̇di̇n Temel

Turkish Journal of Earth Sciences

The Toprakkale (Osmaniye) region, located in the Yumurtalık fault zone in southern Turkey, contains Quaternary volcanic rocks, shown by their mineralogical and petrographical features to be alkali basaltic and basanitic. These alkaline rocks are enriched in the large ion lithophile elements (LILE) Ba, Th and U, and show light rare earth element (LREE) enrichment relative to heavy rare earth element (HREE) on primitive mantle trace and rare earth element patterns that indicate different partial melting of the same source. The isotopic 87Sr/86Sr ratio is relatively low (0.703534-0.703575 for the alkali basalts and 0.703120-0.703130 for the basanites) and the 143Nd/144Nd ratio …


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 …


Geochemical And Sr-Nd Isotopic Characteristics Of Post-Collisional Calc-Alkaline Volcanics In The Eastern Pontides (Ne Turkey), Abdullah Kaygusuz, Mehmet Arslan, Wolfgang Siebel, Cüneyt Şen Jan 2011

Geochemical And Sr-Nd Isotopic Characteristics Of Post-Collisional Calc-Alkaline Volcanics In The Eastern Pontides (Ne Turkey), Abdullah Kaygusuz, Mehmet Arslan, Wolfgang Siebel, Cüneyt Şen

Turkish Journal of Earth Sciences

Major, trace element, K-Ar age and Sr-Nd isotopic data are presented for the Eocene Torul volcanics in the eastern Pontide orogenic belt (NE Turkey). The studied rocks are composed of basaltic andesitic, andesitic, trachyandesitic, and minor trachydacitic lavas associated with their pyroclastics. These rocks contain plagioclase (An2-44), hornblende (Mg#= 0.78-0.98), clinopyroxene (Wo43-46 En41-43 Fs10-15), biotite, quartz, and minor sanidine phenocrysts. K-Ar ages on hornblendes ages range from 43.99 (±2.59) to 33.45 (±2.32) Ma, within the Middle to Late Eocene. The volcanic rocks show calc-alkaline affinities and have medium to high K contents. They are enriched in large ion lithophile (LILE) …


Short Note On The Use Of Neotectonic And Palaeotectonic Nomenclature, Douwe J.J. Van Hinsbergen Jan 2011

Short Note On The Use Of Neotectonic And Palaeotectonic Nomenclature, Douwe J.J. Van Hinsbergen

Turkish Journal of Earth Sciences

The terms 'palaeotectonic' and 'neotectonic' are entrenched in the literature of Anatolian geology, used to subdivide the tectonic history before and after the last major tectonic change, which is frequently linked to the Arabia-Eurasia collision and the onset of westward Anatolian escape along the North Anatolian Fault Zone. This short note, however, illustrates that many different authors use different definitions for the age and cause of onset, and style of 'neotectonics', leading to needless confusion in Turkish geological literature. In addition, in recent years it has become common practice to use the neotectonic period as a stratigraphic correlation tool, leading …


First Records Of Late Devonian Entomozoacean Ostracods In North-Western Turkey, Ati̇ke Nazi̇k, Helga Groos-Uffenorde Jan 2011

First Records Of Late Devonian Entomozoacean Ostracods In North-Western Turkey, Ati̇ke Nazi̇k, Helga Groos-Uffenorde

Turkish Journal of Earth Sciences

Entomozoacean ostracods (pelagic socalled fingerprint-ostracods) have recently been observed for the first time in Upper Devonian sediments of the Darlık B Section from the İstanbul region, north-western Turkey. These new assemblages consist of Entomoprimitia nitida, Entomoprimitia sartenaeri, Entomoprimitia concentrica, Franklinella calcarata, Waldeckella erecta?, Rabienella n. sp. c, aff. reichi sensu Rabien & Rabitz 1958, Rabienella reichi, Richterina (Volkina) zimmermanni and Nehdentomis pseudorichterina and can be dated as Late Frasnian Entomoprimitia sartenaeri Zone (= variostriata Zone sensu Rabien 1954). These entomozoacean ostracods indicate a faunal relationship with Germany (Rhenish Schiefergebirge, Harz Mountains, Thuringia), Poland (Holy Cross Mountains), N France-Belgium (Ardennes), Volgo-Ural …


First Report Of A Trilobite In The Carboniferous Of Eastern Pontides, Ne Turkey, Rai̇f Kandemi̇r, Rudy Lerosey-Aubril Jan 2011

First Report Of A Trilobite In The Carboniferous Of Eastern Pontides, Ne Turkey, Rai̇f Kandemi̇r, Rudy Lerosey-Aubril

Turkish Journal of Earth Sciences

The pre-Mesozoic basement of the Eastern Pontides consists of a Permo-Carboniferous sedimentary sequence including the Çatalçeşme and Hardişi formations. The Çatalçeşme Formation has yielded rich assemblages of fusulinids, corals, gastropods, brachiopods, bryozoans, algae, conodonts and plants. Hitherto trilobites were unknown from this formation; here we report the discovery of a pygidium from a dark grey limestone bed near the top. Trilobites are a minor component of benthic marine communities during the Late Pennsylvanian, and to our knowledge, the discovery of this pygidium constitutes the first report of their occurrence in deposits of this age in Turkey. The morphological characteristics of …


A New Species Of Angariid Gastropod From The Early Thanetian Of The Haymana-Polatlı Basin, Turkey, İzzet Hoşgör, Yavuz Okan Jan 2011

A New Species Of Angariid Gastropod From The Early Thanetian Of The Haymana-Polatlı Basin, Turkey, İzzet Hoşgör, Yavuz Okan

Turkish Journal of Earth Sciences

A new trochoidean species, Angaria calvii n. sp., from the early Thanetian of the Kırkkavak Formation (Haymana-Polatlı Basin, Palaeocene) in central Anatolia, is described and placed in the family Turbinidae. Previously, the oldest Cenozoic Angaria was recorded from the Early Palaeocene (Danian) in France (Paris Basin). In this paper, we report the second discovery of the oldest angariid specimens from the Thanetian sediments of the Tethys realm, a stratigraphic position which is supported by the foraminiferal-red alga assemblages at this locality.


Integrated Oligocene−Lower Miocene Larger And Planktonic Foraminiferal Biostratigraphy Of The Kahramanmaraş Basin (Southern Anatolia, Turkey), Uğraş Işik, Aynur Hakyemez Jan 2011

Integrated Oligocene−Lower Miocene Larger And Planktonic Foraminiferal Biostratigraphy Of The Kahramanmaraş Basin (Southern Anatolia, Turkey), Uğraş Işik, Aynur Hakyemez

Turkish Journal of Earth Sciences

An integrated biostratigraphical analysis based on the larger and planktonic foraminifera from three sections provides a well-defined zonal scheme of the Oligocene-Lower Miocene successions in the Kahramanmaraş Basin. The planktonic foraminiferal zonation is based on a combination of standard (P) and Mediterranean (MMi) zonal schemes and consists of Turborotalia ampliapertura (P19), Globigerina angulisuturalis-Paragloborotalia opima opima (P21), Globigerina ciperoensis (P22) biozones spanning the Upper Rupelian-Chattian interval and Globoquadrina dehiscens-Globigerinoides altiaperturus (MMi 2a), Globigerinoides altiaperturus-Catapsydrax dissimilis (MMi 2b) and Globigerinoides trilobus (MMi 3) biozones in the Upper Aquitanian-Burdigalian interval. The larger foraminiferal zonation of the studied successions has been established by means …


New Data On The Dasycladales From The Lower Eocene Of Seyitgazi Region, Eskişehir, Central Turkey, Rajka Radoicic, Nazi̇re Erdem Jan 2011

New Data On The Dasycladales From The Lower Eocene Of Seyitgazi Region, Eskişehir, Central Turkey, Rajka Radoicic, Nazi̇re Erdem

Turkish Journal of Earth Sciences

An association of Dasycladalean algae is identified from the Lower Eocene (Ilerdian-Cuisian) of the Seyitgazi area, Western Anatolia. The association consists mostly of the genus Belzungia Morellet and Anatolia n. gen. This is the first discovery of such a rich and diversified dasycladalean flora with Belzungia in the Eocene of Central Tethys. The genus Belzungia is represented by four species: Belzungia terquemi Morellet, B. silvestrii (Pfender), B. bella (Ju Ying) Radoicic and B. pfenderae n. sp. Belzungia articles consist of whorls characterized by an assemblage of laterals, in the transversal section of which, the primary laterals are distally enlarged (sub-triangular …


Geodynamic Significance Of The Early Triassic Karaburun Granitoid (Western Turkey) For The Opening History Of Neo-Tethys, Cüneyt Akal, Osman Ersi̇n Koralay, Osman Candan, Oberhaensli Roland, Fukun Chen Jan 2011

Geodynamic Significance Of The Early Triassic Karaburun Granitoid (Western Turkey) For The Opening History Of Neo-Tethys, Cüneyt Akal, Osman Ersi̇n Koralay, Osman Candan, Oberhaensli Roland, Fukun Chen

Turkish Journal of Earth Sciences

The Karaburun Peninsula, which is considered part of the Anatolide-Tauride Block of Turkey, contains clastic and carbonate sequences deposited on the northern margin of Gondwana. The Palaeozoic clastic sequence, which is intruded by the Early Triassic granitoid and tectonically overlies a Mesozoic mélange sequence, can be divided into three subunits: a lower clastic subunit consisting of a sandstone-shale alternation, an upper clastic subunit consisting of black chert-bearing shales, sandstone and conglomerate, and a Permo-Carboniferous carbonate subunit. The lower Triassic Karaburun I-type granitoid has a high initial ^8^7Sr/^8^6Sr ratio (0.709021-0.709168), and low ^1^4^3Nd/^1^4^4Nd ratio (0.512004-0.512023) and \epsilonNd (-5.34 to -5.70) isotopic …


Geology And Tectonic Emplacement Of Eclogite And Blueschists, Biga Peninsula, Northwest Turkey, Firat Şengün, Erdi̇nç Yi̇ği̇tbaş, İsmai̇l Onur Tunç Jan 2011

Geology And Tectonic Emplacement Of Eclogite And Blueschists, Biga Peninsula, Northwest Turkey, Firat Şengün, Erdi̇nç Yi̇ği̇tbaş, İsmai̇l Onur Tunç

Turkish Journal of Earth Sciences

The Biga Peninsula in northwestern Anatolia is a tectonic mosaic, comprising different tectonic units, representing the Sakarya Continent and oceanic assemblages of different origin and ages. The Çamlıca metamorphic association, a member of this orogenic mosaic in the westernmost part of the peninsula, is subdivided into three formations, from bottom to top; the Andıktaşı formation, the Dedetepe formation, and the Salihler formation. Eclogite-facies metamorphic rocks occur as tectonic slices within schist-marble intercalations of the Dedetepe formation. These slices, about 2 km long and 500 m wide, include two different rock types; (i) quartz-mica schists, and (ii) metabasite lenses with eclogite/blueschist …


Sphalerite Associated With Pyrrhotite-Chalcopyrite Ore Occurring In The Kotana Fe-Skarn Deposit (Giresun, Ne Turkey): Exsolution Or Replacement, Emi̇n Çi̇ftçi̇ Jan 2011

Sphalerite Associated With Pyrrhotite-Chalcopyrite Ore Occurring In The Kotana Fe-Skarn Deposit (Giresun, Ne Turkey): Exsolution Or Replacement, Emi̇n Çi̇ftçi̇

Turkish Journal of Earth Sciences

The Kotana prospect is located about 30 km south of Giresun (NE Turkey). The ore mineralization is a Fe-skarn occurring within the low-grade pre-Lower Jurassic Pınarlar metamorphics, consisting of marble-phyllite intruded by the Upper Cretaceous-Eocene Aksu biotite monzogranite. The principal primary ore minerals include pyrrhotite and magnetite along with minor pyrite (I) and chalcopyrite, accompanied by trace sphalerite. Sphalerite is closely associated with chalcopyrite and to a lesser extent with hexagonal pyrrhotite. Secondary ore minerals include pyrite (II), marcasite, martite, hematite, goethite, lepidocrocite, and intermediate Fe-oxides-hydroxides. Gangue minerals are mainly calcite and quartz. Oxidation of the primary sulphides resulted in …


Lagrangian Prediction And Correlation Analysis With Eulerian Data, Mi̇ne Çağlar, Taylan Bi̇lal, Leonid Piterbarg Jan 2011

Lagrangian Prediction And Correlation Analysis With Eulerian Data, Mi̇ne Çağlar, Taylan Bi̇lal, Leonid Piterbarg

Turkish Journal of Earth Sciences

A velocity field obtained from the ocean surface by high-frequency radar is used to test Lagrangian prediction algorithms designed to evaluate the position of a particle given its initial position and observations of several other simultaneously released particles. The problem is motivated by oceanographic applications such as search and rescue operations and spreading pollutants, especially in coastal regions. The prediction skill is essentially determined by temporal and spatial covariances of the underlying velocity field. For this reason correlation analysis of both Lagrangian and Eulerian velocities was carried out. Space covariance functions and spectra of the velocity field are also presented …


The North Anatolian Fault On The Hersek Peninsula, Turkey: Its Geometry And Implications For The 1999 İzmit Earthquake Rupture Propagation, Özgür Kozaci, Erhan Altunel, Scott Lindvall, Charles Brankman, William Lettis Jan 2011

The North Anatolian Fault On The Hersek Peninsula, Turkey: Its Geometry And Implications For The 1999 İzmit Earthquake Rupture Propagation, Özgür Kozaci, Erhan Altunel, Scott Lindvall, Charles Brankman, William Lettis

Turkish Journal of Earth Sciences

The western termination of the 1999 İzmit earthquake still remains as an intriguing problem for researchers and the people residing around the Sea of Marmara. There have been numerous offshore mapping and modelling studies performed in the Gulf of İzmit. However, the main debate about the western termination of the 1999 İzmit surface rupture is linked to the Hersek Peninsula and corresponding fault geometry. We focused our efforts at resolving the fault geometry on the Hersek Peninsula by applying geological mapping, geomorphic analyses, palaeoseismic trenching and geophysical surveys. Our studies reveal that the North Anatolian Fault forms a restraining stepover …


Palaeoseismological Investigations On The Karadere Segment, North Anatolian Fault Zone, Turkey, Aynur Di̇kbaş, Hüsnü Serdar Akyüz Jan 2011

Palaeoseismological Investigations On The Karadere Segment, North Anatolian Fault Zone, Turkey, Aynur Di̇kbaş, Hüsnü Serdar Akyüz

Turkish Journal of Earth Sciences

The Karadere segment of the North Anatolian Fault (NAF) is the easternmost part that ruptured during the 17 August 1999 İzmit earthquake (Mw 7.4). It has a different orientation, at N65°E to other segments which have a nearly E-W trend, and lesser dextral displacement, with maximum 2.3 m in contrast with 5.2 m in the ruptured neighbouring western segment. Two palaeoseismological trenches, at Kazimiye and Karadere sites, were excavated on the central part of the Karadere segment to determine the timing of past earthquakes. Excavation of the Kazimiye site revealed the occurrence of five past events since the 4th century …


Western Termination Of The Mw 7.4, 1999 İzmit Earthquake Rupture: Implications For The Expected Large Earthquake In The Sea Of Marmara, Gülsen Uçarkuş, Zi̇yadi̇n Çakir, Rolando Armijo Jan 2011

Western Termination Of The Mw 7.4, 1999 İzmit Earthquake Rupture: Implications For The Expected Large Earthquake In The Sea Of Marmara, Gülsen Uçarkuş, Zi̇yadi̇n Çakir, Rolando Armijo

Turkish Journal of Earth Sciences

The Mw 7.4, August 17, 1999 İzmit earthquake ruptured a ~100-km-long onshore section of the North Anatolian Fault (NAF) in the eastern Marmara region, causing the loss of more than 20,000 people and extensive destruction. The western termination and total length of the earthquake rupture is still a matter of debate because the surface rupture goes offshore in the Gulf of İzmit after displaying a coseismic displacement of ~5 m. Such a considerable slip implies that the fault rupture must definitely continue some distance westward on the sea floor, but where exactly it terminated is difficult to determine. This issue …


Palaeoearthquakes On The Kelkit Valley Segment Of The North Anatolian Fault, Turkey: Implications For The Surface Rupture Of The Historical 17 August 1668 Anatolian Earthquake, Cengi̇z Zabci, Hüsnü Serdar Akyüz, Volkan Karabacak, Taylan Sançar, Erhan Altunel, Hali̇l Gürsoy, Orhan Tatar Jan 2011

Palaeoearthquakes On The Kelkit Valley Segment Of The North Anatolian Fault, Turkey: Implications For The Surface Rupture Of The Historical 17 August 1668 Anatolian Earthquake, Cengi̇z Zabci, Hüsnü Serdar Akyüz, Volkan Karabacak, Taylan Sançar, Erhan Altunel, Hali̇l Gürsoy, Orhan Tatar

Turkish Journal of Earth Sciences

The 26 December 1939 Erzincan (Ms= 7.8) and 20 December 1942 Erbaa-Niksar (Ms= 7.1) earthquakes created a total surface rupture more than 400 km between Erzincan and Erbaa on the middle to eastern sections of the North Anatolian Fault. These two faulting events are separated by a 10-km-wide releasing stepover, which acted like a seismic barrier in the 20th century. To understand the rupture behaviour in this structurally complex section of the North Anatolian Fault, we undertook palaeoseismological trench investigations on the Kelkit Valley segment where there is little or no palaeoseismic information. We found evidence for three surface faulting …


Geological, Geomorphological And Archaeoseismological Observations Along The Cibyra Fault And Their Implications For The Regional Tectonics Of Sw Turkey, Volkan Karabacak Jan 2011

Geological, Geomorphological And Archaeoseismological Observations Along The Cibyra Fault And Their Implications For The Regional Tectonics Of Sw Turkey, Volkan Karabacak

Turkish Journal of Earth Sciences

In this paper, the Cibyra segment of the Fethiye-Burdur Fault Zone (FBFZ) is investigated using direct field evidence, which helps clarify the controversial behaviour of this zone. The remains of the ancient city of Cibyra which is located on the Cibyra Fault provide invaluable data in documenting traces of fault deformations and related palaeoearthquakes. Slickensides on fault planes, deflected stream beds and terraces, fault-parallel elongated ridges along the Cibyra Fault are the clearest surface evidence for left-lateral faulting. Archaeoseismological evidence in the ancient city is consistent with the geological and geomorphological observations along the fault. Based on detailed field observations, …


The 6 September 2009 Mw5.4 Earthquake In Eastern Albania – Fyrom Border: Focal Mechanisms, Slip Model, Shakemap, Anastasia Kiratzi Jan 2011

The 6 September 2009 Mw5.4 Earthquake In Eastern Albania – Fyrom Border: Focal Mechanisms, Slip Model, Shakemap, Anastasia Kiratzi

Turkish Journal of Earth Sciences

On 6 September 2009 (GMT 21:49) a moderate Mw5.4 earthquake sequence burst at the eastern border of Albania with the Former Yugoslav Republic of Macedonia (FYROM). The main shock was located ~6 km north of the epicentre of the 30 November 1967 Mw6.2 Dibra (or Debar) earthquake, which caused loss of life and considerable damage to buildings. We use broad band waveforms recorded by the Hellenic Unified Seismic Network (HUSN), which receives real-time waveforms from the neighbouring networks, to compute focal mechanisms, obtain the slip model and derive the Shake Map of the mainshock. The focal mechanisms of 18 of …


Geological And Palaeoseismological Evidence For Late Pleistocene−Holocene Activity On The Manisa Fault Zone, Western Anatolia, Çağlar Özkaymak, Hasan Sözbi̇li̇r, Bora Uzel, Hüsnü Serdar Akyüz Jan 2011

Geological And Palaeoseismological Evidence For Late Pleistocene−Holocene Activity On The Manisa Fault Zone, Western Anatolia, Çağlar Özkaymak, Hasan Sözbi̇li̇r, Bora Uzel, Hüsnü Serdar Akyüz

Turkish Journal of Earth Sciences

In West Anatolia near the cities of İzmir and Manisa, the historical occurrence of large earthquakes suggests the presence of important seismogenic faults. However, these faults have yet to be investigated in detail. The Manisa Fault Zone (MFZ) is an active large-scale normal fault system in this area, and thus field observations and palaeoseismological studies of this zone are important for predicting future earthquakes. Hence we sought to document geological and palaeoseismological evidence for Holocene activity on the MFZ. We performed trenching to determine the magnitude and timing of past surface-faulting events using detailed fault-trace mapping, measurements of Upper Pleistocene-Lower …


Geology Of The Caucasus: A Review, Shota Adamia, Guram Zakariadze, Tamar Chkhotua, Nino Sadradze, Nino Tsereteli, Aleksandre Chabukiani, Aleksandre Gventsadze Jan 2011

Geology Of The Caucasus: A Review, Shota Adamia, Guram Zakariadze, Tamar Chkhotua, Nino Sadradze, Nino Tsereteli, Aleksandre Chabukiani, Aleksandre Gventsadze

Turkish Journal of Earth Sciences

The structure and geological history of the Caucasus are largely determined by its position between the still-converging Eurasian and Africa-Arabian lithospheric plates, within a wide zone of continental collision. During the Late Proterozoic-Early Cenozoic, the region belonged to the Tethys Ocean and its Eurasian and Africa-Arabian margins where there existed a system of island arcs, intra-arc rifts, back-arc basins characteristic of the pre-collisional stage of its evolution of the region. The region, along with other fragments that are now exposed in the Upper Precambrian-Cambrian crystalline basement of the Alpine orogenic belt, was separated from western Gondwana during the Early Palaeozoic …


Great Caucasus (Cavcasioni): A Long-Lived North-Tethyan Back-Arc Basin, Shota Adamia, Victor Alania, Aleksandre Chabukiani, Zurab Kutelia, Nino Sadradze Jan 2011

Great Caucasus (Cavcasioni): A Long-Lived North-Tethyan Back-Arc Basin, Shota Adamia, Victor Alania, Aleksandre Chabukiani, Zurab Kutelia, Nino Sadradze

Turkish Journal of Earth Sciences

The Great Caucasus is a northwest-southeast-directed mountain range more than 1100 km long, located between the Black Sea and Caspian Sea. It represents an intracontinental tectonic system resulting from the Late Cenozoic structural inversion of a Palaeozoic-Mesozoic-Early Cenozoic back-arc basin (Dizi basin) in response to the convergence of the Africa-Arabian and Eurasian lithospheric plates. It is bounded to the south by the Transcaucasian massif, a palaeo-island-arc, and to the north by the Scythian platform. The Great Caucasus fold-and-thrust mountain belt is characterized by complete, intensive folding, mainly south vergent imbricated thrusting, close-joint cleavage etc. Structural relationships of the Great Caucasian …