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Mineral-Chemical Constraints On The Miocene Calc-Alkaline And Shoshonitic Volcanic Rocks Of Western Turkey: Disequilibrium Phenocryst Assemblages As Indicators Of Magma Storage And Mixing Conditions, Ercan Aldanmaz Jan 2006

Mineral-Chemical Constraints On The Miocene Calc-Alkaline And Shoshonitic Volcanic Rocks Of Western Turkey: Disequilibrium Phenocryst Assemblages As Indicators Of Magma Storage And Mixing Conditions, Ercan Aldanmaz

Turkish Journal of Earth Sciences

Early to Middle Miocene (22 to 15 Ma) volcanic activity across western Turkey produced a series of lavas and pyroclastic deposits with calc-alkaline and shoshonitic affinities. The erupted magmas show a broad range of compositions from basaltic to rhyolitic (48-75 SiO2 wt%) and are composed of variable phenocryst assemblages. Petrographic and mineral-chemical characteristics suggest that the magmas underwent hydrous crystallization in deep crustal magma chambers that was dominated by plagioclase + pyroxene + pargasitic amphibole fractionation. Subsequent crystallization in shallower magma chambers followed two different trends: (1) anhydrous (pyroxene + plagioclase-dominated); and (2) hydrous (plagioclase + edenitic amphibole + pyroxene-dominated). …


Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay Jan 2006

Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay

Turkish Journal of Earth Sciences

The Menderes Massif, which covers a large area in western Turkey, is made up of Pan-African basement rocks and a Palaeozoic to Early Tertiary cover sequence. The study area is located in the Dalama and Hallaçlar (Aydın) area, in the northern and central parts of the Çine submassif of the Menderes Massif. The oldest units of the Pan-African basement are metaclastics, consisting of paragneisses and mica schists that gradually and conformably overlay paragneisses. Macroscopic appearances and mineralogical and textural data indicate that paragneisses can be subdivided into four subgroups. These are: (1) black spotted, (2) white spotted, (3) massive, grey-coloured …


A Miocene Palaeovalley Network In The Western Taurus (Turkey), Olivier Monod, Catherina Kuzucuoğlu, Aral İ. Okay Jan 2006

A Miocene Palaeovalley Network In The Western Taurus (Turkey), Olivier Monod, Catherina Kuzucuoğlu, Aral İ. Okay

Turkish Journal of Earth Sciences

Lower Miocene conglomerates in the Köprü and Manavgat basins contain pebbles that can be confidently traced back to their source areas, owing to their distinctive lithologies. Among others, are the green Huğlu volcanics (Late Trias), known only in allochthonous units from the Beyşehir region, or the Alanya blueschists, restricted to the Sugözü unit in the Alanya Massif. The problem is to find out how this detrital material could have travelled about eighty kilometres through the Taurus calcareous units during the Miocene. Fortunately, the present drainage system is not yet fully reorganised in the Taurus, and large areas of the chain …


Contact Metamorphism Around The Eocene Saraycık Granodiorite, Eastern Pontides, Turkey, Gülteki̇n Topuz Jan 2006

Contact Metamorphism Around The Eocene Saraycık Granodiorite, Eastern Pontides, Turkey, Gülteki̇n Topuz

Turkish Journal of Earth Sciences

The Eocene Saraycık granodiorite, eastern Pontides, Turkey, is a small post-tectonic intrusive body (~11 km2), cross-cutting tectonically juxtaposed distinct metamorphic and non-metamorphic lithologies. A ~0.8 to 1-km-wide contact-metamorphic aureole has developed around the intrusion. Disequilibrium is prevalent in all lithologies, even in the inner zones of the contact aureole. Conditions of contact metamorphism are estimated by simple phase equilibria applied to microdomains in the metapelitic lithologies without obvious signs of disequilibrium: Shallow emplacement depths (0.21±0.05 GPa = ~5-8 km) are suggested by contact-metamorphic mineral assemblages (e.g., andalusite + corundum + K-feldspar), by Al-in-hornblende barometry on granodiorite and by partial melting …


Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay Jan 2006

Comment On “Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing”, Gülteki̇n Topuz, Aral İ. Okay

Turkish Journal of Earth Sciences

No abstract provided.


Origin And Tectonic Significance Of The Metamorphic Sole And Isolated Dykes Of The Divriği Ophiolite (Sivas, Turkey): Evidence For Slab Break-Off Prior To Ophiolite Emplacement, Osman Parlak, Hüseyi̇n Yilmaz, Durmuş Boztuğ Jan 2006

Origin And Tectonic Significance Of The Metamorphic Sole And Isolated Dykes Of The Divriği Ophiolite (Sivas, Turkey): Evidence For Slab Break-Off Prior To Ophiolite Emplacement, Osman Parlak, Hüseyi̇n Yilmaz, Durmuş Boztuğ

Turkish Journal of Earth Sciences

The Late Cretaceous Divriği ophiolite of east-central Anatolia comprises, from bottom to top, an ophiolitic mélange, metamorphic sole and remnants of oceanic lithosphere. The ophiolitic mélange has been thrust onto the Lower Carboniferous-Campanian Munzur Limestone (Tauride platform), and is in turn tectonically overlain by the metamorphic sole. The metamorphic-sole rocks are represented by amphibolite, plagioclase amphibolite, plagioclase-amphibole schist, plagioclase-epidote-amphibole schist and calc-schist. The oceanic-lithosphere remnant exhibits a complete section, excluding volcanic rocks, comprising mantle tectonites, ultramafic to mafic cumulates, isotropic gabbros and sheeted dykes. Isolated dykes intrude the metamorphic sole and mantle tectonites at different structural levels. The metamorphic-sole rocks …


Mohr-Circle-Based Rotational Invariants Of A Magnetotelluric Data Set From The Thrace Region Of Turkey: Geological Implications, Murat Bayrak, Aysan Gürer, Ö. Feyzi̇ Gürer, O. Meti̇n İlkişik, Ahmet T. Başokur Jan 2006

Mohr-Circle-Based Rotational Invariants Of A Magnetotelluric Data Set From The Thrace Region Of Turkey: Geological Implications, Murat Bayrak, Aysan Gürer, Ö. Feyzi̇ Gürer, O. Meti̇n İlkişik, Ahmet T. Başokur

Turkish Journal of Earth Sciences

In the summer of 1995, magnetotelluric data were acquired at forty sites along a southwest-northeast profile crossing northwestern Turkey in continental Europe. The traverse, 204 km in length, crossed the boundary between a metamorphic mass called the Istranca Massif and a large Tertiary sedimentary basin called the Thrace Basin. The pseudosections of Mohr-circle-based rotational invariant characteristics of the magnetotelluric data such as central impedance (d3), anisotropy angle (l) and phase of central impedance (fd3) were prepared with classical magnetotelluric parameters (apparent resistivity and impedance phase), and detailed Mohr-circle displays were shown for selected stations as a function of the Bostick …


Volcanism And Its Contribution To Mudrock Genesis, Warren Huff Jan 2006

Volcanism And Its Contribution To Mudrock Genesis, Warren Huff

Turkish Journal of Earth Sciences

Explosive eruptions from volcanoes are recorded in the stratigraphic record throughout the Phanerozoic. The most visible evidence of these eruptions is generally in the form of preserved tephra layers, and they appear to be concentrated in the stratigraphic record at times of active plate collision and concomitant high stands of sea level. The products of volcanic eruptions are lavas, tephra and gases, and whereas low-silica, anhydrous basaltic magmas are usually erupted in the form of lava flows high-silica, hydrous rhyolitic magmas are commonly explosively erupted as plinian and ultraplinian plumes, and associated pyroclastic flows. Fallout tephras may be preserved in …


3d-Architecture And Neogene Evolution Of The Malatya Basin: Inferences For The Kinematics Of The Malatya And Ovacık Fault Zones, Nuretdi̇n Kaymakçi, Murat İnceöz, Pinar Ertepinar Jan 2006

3d-Architecture And Neogene Evolution Of The Malatya Basin: Inferences For The Kinematics Of The Malatya And Ovacık Fault Zones, Nuretdi̇n Kaymakçi, Murat İnceöz, Pinar Ertepinar

Turkish Journal of Earth Sciences

The 3D-architecture of the Malatya Basin was studied using remote sensing, seismic interpretation, and palaeostress analysis in the context of the Malatya-Ovacık fault zone. The results indicate that the Ovacık and Malatya fault zones are not different segments of a single 'so called' Malatya-Ovacık fault zone; rather, they are two different fault zones that have operated independently. In addition, the Ovacık fault zone is delimited in the west by the Malatya fault zone, which extends farther north from the point of supposed junction. Maximum individual deflection of streams along the Ovacık fault zone is about 9.3 km, and summation of …


Stratigraphic And Palaeoenvironmental Significance Of Bartonian–Priabonian (Middle–Late Eocene) Microfossils From The Başçeşme Formation, Denizli Province, Western Anatolia, M. Serkan Akki̇raz, Funda Akgün, Sefer Örçen, Angela Bruch, Volker Mosbrugger Jan 2006

Stratigraphic And Palaeoenvironmental Significance Of Bartonian–Priabonian (Middle–Late Eocene) Microfossils From The Başçeşme Formation, Denizli Province, Western Anatolia, M. Serkan Akki̇raz, Funda Akgün, Sefer Örçen, Angela Bruch, Volker Mosbrugger

Turkish Journal of Earth Sciences

This study explains the stratigraphical and palaeoenvironmental significance of Bartonian-Priabonian (Middle-Late Eocene) fossils, the fauna and flora obtained from the Başçeşme formation of the Çardak-Tokça basin (western Anatolia). The studied sequence is an outcrop from the Başçeşme formation, deposited in a shallow-marine to coastal environment without stratigraphic breaks. Forty genera and 58 species have been recognized in the palynological assemblage of the Başçeşme formation. A well-preserved diverse palynomorph and foraminiferal assemblages yield the Middle-Late Eocene age for the Başçeşme formation. In western Anatolia, mangrove elements Nypa and Pelliciera have been first recorded in this study. The pollen of Mauritia and …


Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu Jan 2006

Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu

Turkish Journal of Earth Sciences

An integrated petrographic and geochemical study of the shales and sandstones of Early Jurassic and Late Cretaceous age in the Yusufeli area (Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting, as well as to evaluate the influence of weathering, hydraulic sorting and recycling processes upon source-rock signature. Depending on their matrix and mineralogical content, the Lower Jurassic sandstones are identified as arkosic arenite and wacke, while the Upper Cretaceous sandstones are defined as lithic arenite and wacke. Elemental ratios such as La/Sc, Cr/Ni, Co/Th, Th/Sc and Cr/Th indicate a mafic source for …


Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari Jan 2006

Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari

Turkish Journal of Earth Sciences

Ferricrete, an iron duricrust, caps Tertiary and Mesozoic rocks around Jaisalmer in the Indian desert. These ferricretes are associated with two distinct present-day landforms. The upper unit is a high-level dissected, rocky structural plain and the lower one a colluvial flat with soft ferricrete gravels. This study pertains to the first situation wherein field observations, micromorphological features and regolith chemistry suggest an in situ origin for the ferricretes, as in the case of the Walther profile. Subsequent tectonism and changes in base level resulted in a shift in processes from weathering to erosion. Episodes of erosion resulted in inversion of …


Cambrian Stratigraphy And Trilobites Of The Samur Dağ Area, South Of Hakkâri, Southeastern Turkey, William T. Dean Jan 2006

Cambrian Stratigraphy And Trilobites Of The Samur Dağ Area, South Of Hakkâri, Southeastern Turkey, William T. Dean

Turkish Journal of Earth Sciences

Carbonates of the higher Koruk Formation at Yayla Tepe, near the Samur Dağ in southeastern Turkey and about 17 km north of the Iraq border, contain peri-Gondwanan Middle Cambrian trilobites typical of the Mediterranean Subprovince; these comprise at least seven genera and include the easternmost records in the Near and Middle East of Eccaparadoxides and the biozonal genus Pardailhania. In the lower half of the succeeding, largely clastic Seydişehir Formation, Upper Cambrian trilobites from six levels in decalcified limestone interbeds include four new species [Coosinoides parthianus, Elegantaspis? montis, Prochuangia turcica, Taishania bassifrons] in addition to Chuangia? sp. and Palaeadotes sp. …


Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça Jan 2006

Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça

Turkish Journal of Earth Sciences

Oligo-Miocene sediments have not been adequately studied biostratigraphically, and a detailed bio-chronostratigraphic framework has not yet been established in Eastern Anatolian basins. Palynomorphs have therefore been correlated with the biozonations of marine dinoflagellates, planktonic foraminifera and calcareous nannoplankton of similar latitudes in combined samples from the Ebulbahar and Kelereşdere measured stratigraphic sections, which are located in the northeastern part of Muş. Palynological (dinoflagellate), foraminiferal micropalaentological, and nannopalaeontological events, correlatable with worldwide defined biozonations, have been documented from uppermost Rupelian to Upper Miocene-Pliocene sediments. First occurrences (FOs) and and last occurrences (LOs) of selected dinoflagellates are important in establishing the biostratigraphic …


Investigation Of Water Masses In İzmir Bay, Western Turkey, Erdem Sayin, İdi̇l Pazi, Canan Eronat Jan 2006

Investigation Of Water Masses In İzmir Bay, Western Turkey, Erdem Sayin, İdi̇l Pazi, Canan Eronat

Turkish Journal of Earth Sciences

The main purpose of this paper is to explore seasonal variability of the local hydrography and investigate the water masses, their seasonal and regional variations in the vicinity of İzmir Bay based on data sets collected between 1994 and 2003. The general water movement characteristics in the bay are provided by CTD data analysis together with Killworth's general circulation model. In the bay, three distinct water masses exist: ASW (Aegean Sea water), IBW (İzmir Bay water) and IBIW (İzmir Bay inner water). Generally, vertically homogenous ASW enters the bay from the north, near Karaburun in winter, and horizontally homogeneous ASW …


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.