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

Physical Sciences and Mathematics Commons

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

Articles 1 - 13 of 13

Full-Text Articles in Physical Sciences and Mathematics

Stratigraphy And Geochronology Of The Early Miocene Volcanic Units In The Bigadiç Borate Basin, Western Turkey, Fuat Erkül, Cahi̇t Helvaci, Hasan Sözbi̇li̇r Jan 2005

Stratigraphy And Geochronology Of The Early Miocene Volcanic Units In The Bigadiç Borate Basin, Western Turkey, Fuat Erkül, Cahi̇t Helvaci, Hasan Sözbi̇li̇r

Turkish Journal of Earth Sciences

Western Turkey has undergone an intense deformation which has given rise to two types of basins since the Late Oligocene: NE-trending and E-W-trending basins situated on the basement rocks of the Menderes Massif, the Sakarya Zone, the Lycian nappes and the Bornova Flysch Zone. One of the NE-trending basins, the Bigadiç borate basin, is located in the Bornova Flysch Zone - a 50-90-km-wide zone between the Sakarya Zone and the Menderes Massif. Lower Miocene successions are dominated by lacustrine, fluvial, evaporitic sedimentary rocks and numerous NE-trending volcanic centres which produced considerable amounts of lava and volcaniclastic detritus in the Bigadiç …


Genetic Relations Between Skarn Mineralization And Petrogenesis Of The Evciler Granitoid, Kazdağ, Çanakkale, Turkey And Comparison With World Skarn Granitoids, Yeşi̇m Yücel Öztürk, Cahi̇t Helvaci, Muharrem Satir Jan 2005

Genetic Relations Between Skarn Mineralization And Petrogenesis Of The Evciler Granitoid, Kazdağ, Çanakkale, Turkey And Comparison With World Skarn Granitoids, Yeşi̇m Yücel Öztürk, Cahi̇t Helvaci, Muharrem Satir

Turkish Journal of Earth Sciences

Most skarn deposits are directly related to magmatic activity, and there is a systematic correlation between the composition of causative plutons and the metal contents of the related skarns. This paper documents the composition of facies within the Evciler pluton and correlations between intrusion composition and the metal contents of associated skarns. There have been previous studies of mines (e.g., Cu mines) in the Evciler district, however, there have been no detailed geological investigations of such ore deposits or associated skarn mineralization. In the Evciler district both calcic exoskarn (garnet-pyroxene) and endoskarn (pyroxene-epidote) occur along the contacts between granitoid and …


Water-Level Changes In Shallow Wells Before And After The 1999 İzmit And Düzce Earthquakes And Comparison With Long-Term Water-Level Observations (1999–2004), Nw Turkey, Cenk Yaltirak, Tolga Yalçin, Erkan Bozkurtoğlu, Gali̇p Yüce Jan 2005

Water-Level Changes In Shallow Wells Before And After The 1999 İzmit And Düzce Earthquakes And Comparison With Long-Term Water-Level Observations (1999–2004), Nw Turkey, Cenk Yaltirak, Tolga Yalçin, Erkan Bozkurtoğlu, Gali̇p Yüce

Turkish Journal of Earth Sciences

It is well known that earthquakes cause hydrological changes, such as drying or flooding of water wells, fluctuations in ground-water levels in wells, changes in water quality, and formation of new springs. Significant drops in ground-water levels in wells were recorded during recent earthquakes in NW Turkey on August 17, 1999 in İzmit and on November 12, 1999 in Düzce. The İzmit earthquake (Ms 7.4) caused pre-seismic water-level changes in wells at Eskişehir, located 118-216 km away from the epicentre. Well-level changes in the Eskişehir, Sakarya, Bursa, Yalova, Yenişehir and İnegöl basins were recorded prior to and after the Düzce …


Evolution Of And Factors Controlling Eocene Sedimentation In The Darende-Balaban Basin, Malatya (Eastern Turkey), Kemal Gürbüz, Murat Gül Jan 2005

Evolution Of And Factors Controlling Eocene Sedimentation In The Darende-Balaban Basin, Malatya (Eastern Turkey), Kemal Gürbüz, Murat Gül

Turkish Journal of Earth Sciences

Collision of the Arabian and Anatolian plates affected evolution of basins located along the southern flank of the Anatolian Plate. The Darende-Balaban foreland basin is one such basin – a basin filled with Upper Cretaceous and Eocene sediments, accumulated unconformably and transgressively above ophiolitic and carbonate basement rocks. This basin is locally surrounded, to the north and south, by Late Jurassic–Early Cretaceous structural highs created by tectonic elements during the collision of Arabia and Anatolia. This paper aims to describe the factors controlling and evolution of the Eocene sedimentation in the Darende-Balaban basin. The basin fill comprises two distinct sequences …


Alpine Metamorphism And Granitoid Magmatism In The Strandja Zone: New Data From The Sakar Unit, Se Bulgaria, Ianko Gerdjikov Jan 2005

Alpine Metamorphism And Granitoid Magmatism In The Strandja Zone: New Data From The Sakar Unit, Se Bulgaria, Ianko Gerdjikov

Turkish Journal of Earth Sciences

The Strandja Zone is a pre-Cenomanian orogen consisting of three tectonic units: the Veleka, Strandja and Sakar units. The first two units display very low-grade Alpine metamorphism, whereas in the Sakar unit the Triassic sediments are metamorphosed to the amphibolite facies. For years this high-grade metamorphism was enigmatic and most of the metamorphic rocks were interpreted as a reworked Precambrian crust of the Rhodope. This contribution begins with a review of the recent data about the structure and evolution of the Sakar unit. Probably the most important recent finding was the demonstration of the lack of a structural break between …


Trilobites From The Çal Tepe Formation (Cambrian), Near Seydişehir, Central Taurides, Southwestern Turkey, William T. Dean Jan 2005

Trilobites From The Çal Tepe Formation (Cambrian), Near Seydişehir, Central Taurides, Southwestern Turkey, William T. Dean

Turkish Journal of Earth Sciences

The type section of the Çal Tepe Formation, near Seydişehir, is reviewed. The basal dolomite member is unfossiliferous, but the succeeding black limestone member (24 m), light-grey limestone member (10.15 m), and red nodular limestone member (46.7 m) are subdivided into thirty-seven numbered, often fossiliferous beds. Trilobites from the black limestone member, late Early Cambrian, exhibit affinities with Morocco, Spain and northwestern Europe; they include one new genus and species (Pamphyliaspis nigra) and three other new species (Condylopyge matutina, Alueva venulosa, Antatlasia scabra). The lower light-grey limestone member contains Acadoparadoxides (Acadoparadoxides) mureroensis, basal Middle Cambrian index species in Spain, with …


Karst In Turkish Thrace: Compatibility Between Geological History And Karst Type, Mehmet Ekmekçi̇ Jan 2005

Karst In Turkish Thrace: Compatibility Between Geological History And Karst Type, Mehmet Ekmekçi̇

Turkish Journal of Earth Sciences

Geographically, Thrace is a region located in southeastern Europe within the territories of Greece, Bulgaria and Turkey. In Turkish Thrace, karst occurs extensively in Eocene limestones, although some limited karst occurs in marble of the metamorphic series of Palaeozoic age. The karstification base is shallow to very shallow and most of the dolines and poljes have been captured by surface streams. Subsurface drainage has been changed to surface drainage in most parts of the region. Caves and cave relicts are concentrated mainly at three different altitudes, and almost all caves are horizontal or sub-horizontal. With these characteristics, Turkish Thrace hosts …


Shape And Size Characteristics Of Bedload Transported During Winter Storm Events In The Cwm Treweryn Stream, Brecon Beacons, South Wales, Tuncer Demi̇r, R. P. D. Walsh Jan 2005

Shape And Size Characteristics Of Bedload Transported During Winter Storm Events In The Cwm Treweryn Stream, Brecon Beacons, South Wales, Tuncer Demi̇r, R. P. D. Walsh

Turkish Journal of Earth Sciences

Bedload transport in the Cwm Treweryn stream, a tributary of the Usk in the Brecon Beacons, South Wales, was investigated during a wet winter period in early 1995 using basket-type bedload traps and the tracing of painted clasts. The Cwm Treweryn is a typical mountain stream of the region with its gravel-bedload, flashy regime, high gradient and pool-riffle sequences. In particular, the study explored - for a range of categories of clast size - the nature of any influence of clast shape on bedload movement. Competent flows ranging from 2.5 to 19.5 m^3 s^{-1} (the latter close to bankfull flow) …


Laboratory Determination Of Multicomponent Effective Diffusion Coefficients For Heavy Metals In A Compacted Clay, M. Zeki̇ Çamur, Hasan Yazicigi̇l Jan 2005

Laboratory Determination Of Multicomponent Effective Diffusion Coefficients For Heavy Metals In A Compacted Clay, M. Zeki̇ Çamur, Hasan Yazicigi̇l

Turkish Journal of Earth Sciences

Diffusion and sorption of heavy-metal ions (Cd, Cr, Cu, Fe, K, Mn, Ni, Pb, and Zn) through an Ankara clay liner were studied experimentally. The Ankara clay consists of calcite, quartz, smectite and illite, and is a highly plastic inorganic clay with optimum weight water content of 32% and corresponding dry density of 1.413 g/cm3. Under optimum compaction conditions, effective porosity (volumetric water content) and hydraulic conductivity in the material were determined as 0.45 and 1.3 to 2.6x10-9 cm/s, respectively. The Ankara clay adsorbed Cd, Cr, Cu, Fe, K, Mn, Ni, Pb, and Zn metals, but desorbed Ca, Mg and …


Investigation Of Safe And Sustainable Yields For The Sandy Complex Aquifer System In The Ergene River Basin, Thrace Region, Turkey, Şebnem Ökten, Hasan Yazicigi̇l Jan 2005

Investigation Of Safe And Sustainable Yields For The Sandy Complex Aquifer System In The Ergene River Basin, Thrace Region, Turkey, Şebnem Ökten, Hasan Yazicigi̇l

Turkish Journal of Earth Sciences

This study aims to determine the safe and sustainable yields for the Sandy Complex aquifer system in Ergene River basin in northwestern Turkey. A numerical ground-water flow model was developed for the Sandy Complex aquifer, which is the most productive and the most widespread aquifer in the basin. The finite difference ground-water model was used to simulate steady and unsteady flow in the aquifer. The model was calibrated in two steps: a steady-state calibration, by using the observed ground-water levels of January 1970; then a transient calibration, by using the observed ground-water levels for the period of January 1970 and …


Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing, Zafer Arslan Jan 2005

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

There are many acidic intrusions of varying age in the northern and southern zones of the eastern Pontides, NE Turkey, and the Sarıhan Granitoid is one of these. The Maastrichtian Sarıhan Granitoid was emplaced into the pre-Permo-Carboniferous Pulur Massif, generally comprising medium-grade metamorphic rocks; the Liassic Hamurkesen Formation, that begins with the Dikmetaş conglomerate and continues upward into volcano-sedimentary rocks; and the Malm-Lower Cretaceous Hozbirikyayla Formation, comprising limestone and sandy limestones. The Sarıhan Granitoid crops out in an area of approximately 40 km2, has an ellipsoidal shape, and comprises mainly quartz monzodiorite, granodiorite and lesser quartz diorite. The pluton contains …


Stratigraphy Of The Volcanic Products Around Nemrut Caldera: Implications For Reconstruction Of The Caldera Formation, Özgür Karaoğlu, Yavuz Özdemi̇r, A. Ümi̇t Tolluoğlu, Mustafa Karabiyikoğlu, Onur Köse, Jean-Luc Froger Jan 2005

Stratigraphy Of The Volcanic Products Around Nemrut Caldera: Implications For Reconstruction Of The Caldera Formation, Özgür Karaoğlu, Yavuz Özdemi̇r, A. Ümi̇t Tolluoğlu, Mustafa Karabiyikoğlu, Onur Köse, Jean-Luc Froger

Turkish Journal of Earth Sciences

The volcanological development of the Nemrut stratovolcano, located near the southwestern tip of Lake Van in eastern Turkey, is subdivided into three stages: pre-caldera, post-caldera and late stages. Two ignimbrite flows have been recognized in the pre-caldera stage. The earlier of the two occurred after basaltic lavas formed along extensional fissures. The latter, which forms the main subject of this paper, was a major flow associated with the development of the Nemrut caldera. The pyroclastic deposits of the Nemrut volcano in the pre-caldera stage are divided into three phases on the basis of palaeosols that separate them. The first phase …


Geotectonic Setting And Origin Of The Youngest Kula Volcanics (Western Anatolia), With A New Emplacement Model, Murat Tokçaer, Samuele Agostini, Mehmet Yilmaz Savaşçin Jan 2005

Geotectonic Setting And Origin Of The Youngest Kula Volcanics (Western Anatolia), With A New Emplacement Model, Murat Tokçaer, Samuele Agostini, Mehmet Yilmaz Savaşçin

Turkish Journal of Earth Sciences

The Quaternary Kula volcanics are Na-dominant in character while all the older volcanic rocks of western Anatolia are generally definitive K-dominant rocks. As a unique example in western Anatolia, the existence of a huge amount of plateau basalts at Kula indicates rapid uplift of mantle material, as confirmed by new geochemical data. Based on our field observations, the oldest Kula volcanics are the plateau basalts with more than one main lava flow. At the beginning of volcanic activity (first-period plateau basalts), this plateau was vast. Subsequently, parts of the first-period plateau basalts were uplifted and partly eroded while other parts …