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Articles 871 - 900 of 917
Full-Text Articles in Earth Sciences
Repetitive Subtidal-To-Coastal Sabkha Cycles From A Lower-Middle Miocene Marine Sequence, Eastern Sivas Basin, Faruk Ocakoğlu
Repetitive Subtidal-To-Coastal Sabkha Cycles From A Lower-Middle Miocene Marine Sequence, Eastern Sivas Basin, Faruk Ocakoğlu
Turkish Journal of Earth Sciences
In the study area, southeast of Zara in the Sivas Basin, the Lower-Middle Miocene marine Karacaören Formation consists of a succession of marine sedimentary rocks deposited within two trangressive-regressive cycles. The present study focuses on the facies characteristics, cyclic nature, and significance of the basin-wide distribution of a 100-m-thick gypsiferous sedimentary package overlying an otherwise transgressive segment of the lower sequence, within a marine setting. The typical lithologic expression of the studied sedimentary interval comprises generally fossiliferous mudstones, rare algal limestones and nodular gypsum. Detailed sedimentological observations, combined with palaeontological evidence, indicate that the mudstone intervals were deposited in a …
Extensional Tectonics And The Geometry Of Related Macroscopic Structures: Field Evidence From The Gediz Detachment, Western Turkey, Hasan Sözbi̇li̇r
Extensional Tectonics And The Geometry Of Related Macroscopic Structures: Field Evidence From The Gediz Detachment, Western Turkey, Hasan Sözbi̇li̇r
Turkish Journal of Earth Sciences
The large-scale, low-angle Gediz detachment fault that constitutes the southern margin of the Gediz graben (also known as the Alaşehir graben) has macroscopic structures of extensional origin, such as folds and back-tilted strata. The folds were formed as antiformal and synformal structures with axes both parallel and perpendicular to the extensional direction in their footwalls and hanging-walls, respectively. An extension-parallel antiform-synform pair in the footwall of the Gediz detachment, namely the Oyukkıran antiform and the Keserler synform, are recognized south of Dereköy village (Salihli) on the southern margin of the Gediz graben. These are NE-trending domal and basinal structures with …
The June 6, 2000, Orta (Çankırı, Turkey) Earthquake: Sourced From A New Antithetic Sinistral Strike-Slip Structure Of The North Anatolian Fault System, The Dodurga Fault Zone, Ali̇ Koçyi̇ği̇t, Bora Rojay, Mustafa Ci̇han, Arda Özacar
The June 6, 2000, Orta (Çankırı, Turkey) Earthquake: Sourced From A New Antithetic Sinistral Strike-Slip Structure Of The North Anatolian Fault System, The Dodurga Fault Zone, Ali̇ Koçyi̇ği̇t, Bora Rojay, Mustafa Ci̇han, Arda Özacar
Turkish Journal of Earth Sciences
The İsmetpaşa-Kargı section of the North Anatolian Fault System (NAFS) consists of six subfault zones, namely the Eskipazar, the Ulusu, the Tosya, the Çerkeş-Kurşunlu, the Devrez and the newly detected Dodurga fault zone (DFZ). Together these fault zones form a well-developed dextral strike-slip-faulting pattern, in which the DFZ is an antithetic secondary strike-slip component, indicated by focal-mechanism solutions of moderate and large earthquakes that have occurred in the İsmetpaşa-Kargı section of the NAFS. The DFZ is a ~36-km-long, ~N-S-trending strike-slip structure located in the area between Saçak village in the north and Kösrelik village in the south. Pre-Upper Pliocene rocks …
Tectonic Implications Of Some Cretaceous Pillow Basalts From The North Anatolian Ophiolitic Mélange(Central Anatolia-Turkey) To The Evolution Of Neotethys, Bora Rojay, Kenan M. Yaliniz, Demi̇r Altiner
Tectonic Implications Of Some Cretaceous Pillow Basalts From The North Anatolian Ophiolitic Mélange(Central Anatolia-Turkey) To The Evolution Of Neotethys, Bora Rojay, Kenan M. Yaliniz, Demi̇r Altiner
Turkish Journal of Earth Sciences
The most widespread blocks within the North Anatolian ophiolitic mélange of central Anatolia (Turkey) are ophiolitic fragments, Jurassic-Cretaceous carbonate blocks and pillow basalts. The blocks of pillow basalts have an immobile trace-element geochemistry that is characteristic of ocean-island alkali basalts. An N-MORB-normalized spider diagram shows a distinctive enrichment of most incompatible trace elements and exhibits a far greater range of absolute abundances than N-MORB. Selected incompatible-element contents and ratios of basalts show high Ba/Nb (~8),low Zr/Nb(~5)and low La/Nb(~0.5)relative to N-MORB. The presence of thin-shelled \"Protoglobigerina\" and Cadosina associated with miliolids and epistominid foraminifers indicates that the age of the pink …
Post-Collisional Magmatism On The Northern Margin Of The Taurides And Its Geological Implications: Geology And Petrology Of The Yahyalı-Karamadazı Granitoid, Gonca Gençali̇oğlu Kuşcu, M. Cemal Göncüoğlu, İlkay Kuşcu
Post-Collisional Magmatism On The Northern Margin Of The Taurides And Its Geological Implications: Geology And Petrology Of The Yahyalı-Karamadazı Granitoid, Gonca Gençali̇oğlu Kuşcu, M. Cemal Göncüoğlu, İlkay Kuşcu
Turkish Journal of Earth Sciences
The Karamadazı Granitoid (Yahyalı-Kayseri) is a typical example of bimodal magmatism on the northern margin of the Eastern Tauride belt. The Karamadazı Granitoid intrudes the Palaeozoic-Mesozoic Yahyalı metamorphic rocks and is unconformably overlain by Upper Maastrichtian clastics. It consists of granodiorite-quartz diorite as the main intrusive phase, and includes leucogranites and aplitic dykes in its marginal parts. Samples from the Karamadazı Granitoid are calc-alkaline and calcic in character. The granodiorites are mainly metaluminous, whereas leucogranites and aplites are weakly peraluminous in nature. Plots of major-element oxides against SiO2 indicate a poor fractionation trend for the granodiorites. The leucogranites represent highly …
Geochemistry And Mineralogy Of The Skarns In The Çelebi District, Kırıkkale, Turkey, İlkay Kuşcu
Geochemistry And Mineralogy Of The Skarns In The Çelebi District, Kırıkkale, Turkey, İlkay Kuşcu
Turkish Journal of Earth Sciences
The Çelebi district is well known for its polymetallic Fe-W and Cu vein ores. These ores are hosted by calcic skarn zones, which are broadly classified as \"intrusive around skarn\" type. Both exoskarns (pyroxene-garnet) and endoskarns (epidote-pyroxene) occur in the district. The formation of endoskarns is manifested by complete replacement of plagioclase by epidote and pyroxene; the epidotized granitoids are regarded as incipient and/or early metasomatic products. The abundance of pyroxene in endoskarns tends to increase with plagioclase content and within the groundmass of the granitoids towards exoskarn zones. The increase in pyroxene is also coincident with the formation of …
A Proposal For A Method To Establish Natural-Hazard-Based Land-Use Planning: The Adapazarı Case Study, Alper Çabuk
A Proposal For A Method To Establish Natural-Hazard-Based Land-Use Planning: The Adapazarı Case Study, Alper Çabuk
Turkish Journal of Earth Sciences
As a result of recent disasters in northwest Turkey (Marmara earthquake August 17, 1999/Düzce earthquake November 12, 1999), many buildings collapsed and many people experienced physical and mental problems. We can suppose that the problems caused by these earthquakes will be solved in the future, but geological studies show that the problems will not disappear in that many scientists are predicting a new disaster that will affect the same region. A design of natural-hazard land-use planning for minimising the consequences of recent and possible earthquakes is presented herein. The Adapazarı case is used to demonstrate the fundamentals of this study. …
Obituary, Aral İ. Okay, M. Cemal Göncüoğlu
Obituary, Aral İ. Okay, M. Cemal Göncüoğlu
Turkish Journal of Earth Sciences
No abstract provided.
Characteristics Of The Weathering Zones Developed Within The Tuffs Of The Midas Monument, Tamer Topal, Burak Sözmen
Characteristics Of The Weathering Zones Developed Within The Tuffs Of The Midas Monument, Tamer Topal, Burak Sözmen
Turkish Journal of Earth Sciences
The Midas monument, an impressive cult facade located in the southern part of the Eskişehir province in central Anatolia, Turkey, was made within tuffs (white and pink), which now have deterioration problems. In this study, the depth and characteristics of the weathering zones that have developed in the white and pink tuffs have been investigated through thin-section studies, X-ray powder diffractometry, methylene blue adsorption tests, major-element analyses, and some index parameters. It has been determined that the feldspar minerals are mechanically fractured due to weathering. The tuffs contain small amounts of clay minerals. An approximately 1-cm-thick silica-rich zone has developed …
Development Of A Basic Gis Database For The Yeşilırmak Watershed Provinces Using Satellite Images And Other Data, Hülya Yildirim, Erhan Alparslan, Mehmet Emi̇n Özel, Ci̇hangi̇r Aydöner, Samuray Eli̇taş, Nalan Jale Di̇van, Mehmet Dağci, Asli Süha Dönertaş
Development Of A Basic Gis Database For The Yeşilırmak Watershed Provinces Using Satellite Images And Other Data, Hülya Yildirim, Erhan Alparslan, Mehmet Emi̇n Özel, Ci̇hangi̇r Aydöner, Samuray Eli̇taş, Nalan Jale Di̇van, Mehmet Dağci, Asli Süha Dönertaş
Turkish Journal of Earth Sciences
Remote-sensing and geographic-information-systems (GIS) techniques were jointly used in this study to establish a GIS database system for the Yeşilırmak watershed provinces, which include Amasya, Tokat, Çorum, Yozgat and Samsun. Composite multicolour images (down to 6 m resolution) from the LANDSAT TM and Indian IRS C/D satellites, land-use/land-cover maps derived from these images, road networks, soil information, digital terrain model, slope and aspect information derived from digital elevation data and meteorological data at province level are the major constituents of this database. A 'project office' has been established with trained personnel at each province centre to effectively use the resultant …
Devitrification Of Volcanic Glasses In Konya Volcanic Units, Turkey, Zehra Karakaş, Selahatti̇n Kadi̇r
Devitrification Of Volcanic Glasses In Konya Volcanic Units, Turkey, Zehra Karakaş, Selahatti̇n Kadi̇r
Turkish Journal of Earth Sciences
The study area is composed of volcanic, sedimentary and volcano-sedimentary units, which are exposed south and southwest of the city of Konya. XRD analysis indicates that the volcanic units contain halloysite, kaolinite, smectite, illite and sepiolite type clay minerals and opal-CT, feldspar, quartz, minamiite and jarosite type non-clay minerals. SEM studies show that volcanic glasses, which are the main component of the volcanic units, appeared as curviplanar, vesicular-planar and in highly fractured shapes. Fractures and dissolution voids of the volcanic glasses are generally filled by hexagonal kaolinite, fibrous halloysite and smectite. Mineralogical and micromorphological observations indicate that clay minerals were …
Upper Cretaceous Eclogite-Facies Metamorphic Rocks From The Biga Peninsula, Northwest Turkey, Aral İ. Okay, Muharrem Satir
Upper Cretaceous Eclogite-Facies Metamorphic Rocks From The Biga Peninsula, Northwest Turkey, Aral İ. Okay, Muharrem Satir
Turkish Journal of Earth Sciences
Medium-grade metamorphic rocks crop out over a large area under the Neogene sedimentary and volcanic rocks in the central Biga Peninsula in northwest Turkey. These Çamlıca metamorphics consist dominantly of quartz-micaschists with minor calc-schist, marble, quartzite and metabasite. Some of the metabasites in the Çamlıca metamorphics preserve an early eclogite-facies mineral assemblage of garnet + omphacite + glaucophane + rutile ± paragonite, strongly overprinted by greenschist-facies mineral assemblages. The conditions of the eclogite-facies metamorphism have been determined as 510 ± 50°C temperatures and a minimum pressure of 11 kbar, based on the garnet-clinopyroxene Fe-Mg partitioning and the jadeite content of …
Biostratigraphic Data (Mammalia And Palynology) From The Upper Miocene İncesu Formation At Düzyayla (Hafik-Sivas, Central Anatolia), Funda Akgün, Tanju Kaya, Ann Forsten, Zeki̇ Atalay
Biostratigraphic Data (Mammalia And Palynology) From The Upper Miocene İncesu Formation At Düzyayla (Hafik-Sivas, Central Anatolia), Funda Akgün, Tanju Kaya, Ann Forsten, Zeki̇ Atalay
Turkish Journal of Earth Sciences
The Upper Miocene İncesu formation, widely exposed in Düzyayla (Hafik-Sivas), consists of mudstones, conglomerates, lacustrine limestones and lignite. The İncesu formation overlies the gypsiferous Hafik formation of controversial Middle Miocene or Oligocene ages. The mammalian fauna of the lignite horizon includes Hipparion sp., Ceratotherium neumayri (Osborn), Deinotherium giganteum Kaup, Choerolophodon pentelici (Gaudry & Lartet), Adcrocuta cf. eximia (Roth & Wagner), Oioceros wegneri Andree, Helladotherium duvernoyi Gaudry & Lartet and Microstonyx erymanthius (Roth & Wagner), which indicate a Turolian (Late Miocene) age. The palynological assemblage of the lignite is apparently represented by 27 genera and 39 species. Four genera and four …
Borate Deposits Of Turkey And Argentina; A Summary And Geological Comparison, Cahi̇t Helvaci, Ricardo R. Alonso
Borate Deposits Of Turkey And Argentina; A Summary And Geological Comparison, Cahi̇t Helvaci, Ricardo R. Alonso
Turkish Journal of Earth Sciences
No abstract provided.
Geochemistry And Significance Of Mafic Dyke Swarms In The Pozantı-Karsantı Ophiolite (Southern Turkey), Osman Parlak
Geochemistry And Significance Of Mafic Dyke Swarms In The Pozantı-Karsantı Ophiolite (Southern Turkey), Osman Parlak
Turkish Journal of Earth Sciences
The Pozantı-Karsantı ophiolite, which is one of a number of the Late Cretaceous oceanic lithospheric remnants in southern Turkey, is situated in the eastern Tauride belt and consists of three distinct thrust sheets: an ophiolitic melange, a metamorphic sole, and an ophiolitic stratigraphic sequence. These units (except the ophiolitic melange) are intruded by isolated microgabbro-diabase dykes at all structural levels. The dykes from the lower crustal rocks (cumulates) are subalkaline in character and chemically similar to island arc tholeiitic basalts and basaltic andesites. They are enriched in some LIL elements (Rb, Ba, K and Sr) and depleted in HFS elements …
Late Devonian Conodont Fauna Of The Gümüşali Formation, The Eastern Taurides, Turke, Şenol Çapkinoğlu, İsmet Gedi̇k
Late Devonian Conodont Fauna Of The Gümüşali Formation, The Eastern Taurides, Turke, Şenol Çapkinoğlu, İsmet Gedi̇k
Turkish Journal of Earth Sciences
The Late Devonian Gümüşali formation of the eastern Taurides is a terrigenous-carbonate rock sequence about 600 m thick, consisting mainly of quartz sandstone, quartz siltstone, shale, and carbonate rocks. Palaeontologic and sedimentologic data mainly indicate a shallow subtidal depositional environment. This sequence generally represents the shallow-water polygnathid-icriodid biofacies, and contains conodont faunas that range from the Upper falsiovalis Zone into the Upper praesulcata Zone. However, they do not correlate well to the Late Devonian standard conodont zonation because of the lack of zonally diagnostic species and the irregular vertical distributions of the present taxa. Herein, 54 taxa belonging to nine …
Late Devonian (Famennian) Conodonts From Denizliköyü, Gebze, Kocaeli, Northwestern Turkey, Şenol Çapkinoğlu
Late Devonian (Famennian) Conodonts From Denizliköyü, Gebze, Kocaeli, Northwestern Turkey, Şenol Çapkinoğlu
Turkish Journal of Earth Sciences
Late Devonian (Famennian) conodont faunas have been described from two incomplete stratigraphic sections (GD and GB) of the Ayineburnu member of the Tuzla formation, Denizliköyü, Gebze, Kocaeli, northwestern Turkey. The section GD comprises the Lower and Middle expansa Zones, and the section GB contains the Middle and Upper expansa Zones. Zonal indices for the Middle expansa Zone are identified in the section GB, whereas this zone is recognized on the basis of other key taxa in the section GD. Also, a new species of the Genus Branmehla, Branmehla gediki n.sp. is described from the section GD.
Taxonomic And Paelogeographic Approaches To The Dasyclad Algae In The Upper Jurassic (Kimmeridgian)-Upper Cretaceous (Cenomanian) Peritidal Carbonates Of The Fele (Yassıbel) Area (Western Taurides, Turkey), İsmai̇l Ömer Yilmaz
Turkish Journal of Earth Sciences
In the Fele (Yassıbel) area in the north of Beyşehir Lake in the Western Taurides, Upper Jurassic (Kimmeridgian) - Upper Cretaceous (Cenomanian) peritidal carbonates were studied in detail. In this study, 30 species of dasyclad algae were identified and 3 new Salpingoporella species were identified within the peritidal carbonates. It was determined that they belong to 13 different genera: Acroporella, Actinoporella, Campbelliella, Clypeina, Cylindroporella, Epimastopora, Epimastoporella, Kopetdagaria, Macroporella, Otternstella, Rajkaella, Salpingoporella, and Selliporella. Salpingoporella is the dominant genus. Some of the species are new records for Turkey: Clypeina nigra, Clypeina parasolkani, Otternstella lemmensis, Salpingoporella biokovensis, Salpingoporella circassa, Salpingoporella piriniae, and …
Clinopyroxene Compositions Of The Isotropic Gabbros From The Sarıkaraman Ophiolite: New Evidence On Supra-Subduction Zone Type Magma Genesis In Central Anatolia, Kenan M. Yaliniz, M. Cemal Göncüoğlu
Clinopyroxene Compositions Of The Isotropic Gabbros From The Sarıkaraman Ophiolite: New Evidence On Supra-Subduction Zone Type Magma Genesis In Central Anatolia, Kenan M. Yaliniz, M. Cemal Göncüoğlu
Turkish Journal of Earth Sciences
The Sarıkaraman Ophiolite is one of the least dismembered ophiolitic units of the allochthonous Central Anatolian Ophiolites, which retains its recognizable pseudostratigraphy. The Sarıkaraman Ophiolite is represented in its lowermost part by isotropic gabbros. Within the isotropic gabbro sequence, clinopyroxenes are observed as small, colorless relicts with a cloudy appearance. In most of the samples, they are completely replaced by a successive generation of green to brown amphiboles. Clinopyroxenes display diopsitic to augitic compositions within the range of En 45 Fs 5 Wo 49 to En 50 Fs 9 Wo 41 . They are Ca-rich and Na-poor (Na 2 O
Field, Petrographic And Geochemical Features Of The Baranadağ Quartz Monzonite Of The Central Anatolian Granitoids, Turkey, Nurdan S. Aydin, A. Piril Önen
Field, Petrographic And Geochemical Features Of The Baranadağ Quartz Monzonite Of The Central Anatolian Granitoids, Turkey, Nurdan S. Aydin, A. Piril Önen
Turkish Journal of Earth Sciences
The Baranadağ quartz monzonite is one of the granitioid intrusions of the Central Anatolian Crystalline Complex (CACC) which represents the passive continental margin of the Anatolide-Tauride platform. Medium to coarse-grained Baranadağ quartz monzonites typically include mafic microgranular enclaves and K-feldspar megacrysts and are cut by aplitic dykes representing the youngest magmatic activity of the study area. The intrusion is mainly composed of orthoclase, plagioclase, quartz, hornblende, biotite and clinopyroxene. It displays a slightly alkaline character and relatively well-developed calc-alkaline trend. The metaluminous Baranadağ quartz monzonites show comparable field, petrographic and/or geochemical features with those of the H-type (Hybrid) granitoids of …
Biostratigraphic And Environmental Analysis Of The Upper Jurassic- Lower Cretaceous Carbonate Sequence In The Başoba Yayla Area (Trabzon, Ne Turkey), Kemal Tasli, Erol Özer, Cemi̇l Yilmaz
Biostratigraphic And Environmental Analysis Of The Upper Jurassic- Lower Cretaceous Carbonate Sequence In The Başoba Yayla Area (Trabzon, Ne Turkey), Kemal Tasli, Erol Özer, Cemi̇l Yilmaz
Turkish Journal of Earth Sciences
In the Başoba Yayla (Trabzon, NE Turkey) area, which is located in the Eastern Pontides northern zone, platform carbonates were deposited during the Late Jurassic-Early Cretaceous time in environments varying from intertidal/ supratidal to outer shelf. The carbonate sequence begins with a thick dolomite unit of the Late Jurassic to Early Cretaceous age. The following unit is rich in benthic foraminifers and pelecypoda shells. The foraminiferal assemblage comprising Vercorsella laurentii/camposaurii and Pseudolituonella gavonensis indicates a Late Hauterivian to Early Aptian age for this unit. The Late Aptian-Albian facies is characterized by bioclastic wackestones containing benthic foraminifers typical of outer platform …
Deformation Of Stibnites And Pyrites In The Madsan Antimony Deposit (Niğde, Turkey): Implications For Pressure-Temperatureconditions Of Local Deformation, İlkay Kuşcu, Ayhan Erler
Deformation Of Stibnites And Pyrites In The Madsan Antimony Deposit (Niğde, Turkey): Implications For Pressure-Temperatureconditions Of Local Deformation, İlkay Kuşcu, Ayhan Erler
Turkish Journal of Earth Sciences
The Madsan antimony deposit at the southeastern part of the Niğde province (south-central Turkey) includes a series of epithermal veins hosted by marbles and gneisses. The veins have a simple mineralogy of quartz, calcite, stibnite and pyrite as major constituents, and cinnabar occurs in trace amounts. The deposit experienced a progressive deformation evidenced by a set of textures developed especially in stibnite and pyrite. These are pressure lamellae and annealing as the main textures, and curvature, off-set of pressure lamellae and fracture filling as the textures of minor importance. These were developed in three successive deformation phases. Pressure lamellae represent …
Mafic Microgranular Enclaves In The Kozak Granodiorite, Western Anatolia, Cüneyt Akal, Cahi̇t Helvaci
Mafic Microgranular Enclaves In The Kozak Granodiorite, Western Anatolia, Cüneyt Akal, Cahi̇t Helvaci
Turkish Journal of Earth Sciences
Enclaves which are relicts of initial basic magma give important information on the origin and evolution of granitic magmas. The mafic microgranular enclaves from the l-type Kozak pluton are less than 1 m that are located at the margin of pluton and mostly less than 15 cm and are generally in sharp contact with the surrounding granodiorite. In some cases, several enclaves may occur close to each other, but they are not closely clustered to form swarms. Most of the enclaves are ellipsoidal in shape. The largest enclaves are less ellipsoidal with curved boundaries. The mafic microgranular enclaves contain same …
Rock-Forming Nannofossils In Uppermost Jurassic-Lowercretaceous Rock Units Of Northwest Anatolia: Nannoconusand Its Resived Taxonomy, Sevi̇nç Özkan Altiner
Rock-Forming Nannofossils In Uppermost Jurassic-Lowercretaceous Rock Units Of Northwest Anatolia: Nannoconusand Its Resived Taxonomy, Sevi̇nç Özkan Altiner
Turkish Journal of Earth Sciences
Nannoconids have been recorded in a rock-forming quantity in the uppermost Jurassic-Lower Cretaceous rock units in Northwest Anatolia, Turkey. Samples were collected from seventeen stratigraphic sections spanning the calciturbidities of the Yosunlukbayiri Formation and pelagic micrites of the Sogukçam Limestone. Because of rareness and difficulties for extracting of calcareous nannofossil species particularly zone markers in these type lithologies, nannoconids have particular attention in terms of biostratigraphy. Twenty nine species of nannoconids were recorded in the studied samples. Their taxonomy were revised and their stratigraphic ranges were given. The classification of genus Nannoconusis based on the gross morphology of the test, …
Geology Of The Dereiçi (Şavsat, Artvin) Cu-Pb-Zn Deposits, Mesut Soylu, Ayhan Erler
Geology Of The Dereiçi (Şavsat, Artvin) Cu-Pb-Zn Deposits, Mesut Soylu, Ayhan Erler
Turkish Journal of Earth Sciences
The geological relationships between the rock units in the Dereiçi/Şavsat (Artvin) region and vein-type Cu-Pb-Zn deposits were presented in this paper. The study area comprises the Upper Cretaceous intermediate volcanic rocks and sedimentary rocks, with Post-Eocene dykes of andesitic and diabasic composition. The mineral deposits are classified as (1) Sphalerite-Galena-Chalcopyrite-Pyrite veins (Talatin Madeni, Binektasi and Fikrinin Madeni), (2) milky quartz-Chalcopyrite-Sphalerite-Galena-Pyrite veins and (3) Chalcopyrite-Pyrite veins. The general paragenetic sequence of the mineralizations is observed as quartz I-pyrite-chalcopyrite-sphalerite-galena-quartz II-chalcocite-covellite. The wall rocks are subjected to silicification, sericitic alteration, chloritization and carbonatization.
Along-Strike Discontinuity Of Active Normal Faults And Its Influence On Quaternary Travertine Deposition; Examples From Western Turkey, Zi̇yadi̇n Çakir
Along-Strike Discontinuity Of Active Normal Faults And Its Influence On Quaternary Travertine Deposition; Examples From Western Turkey, Zi̇yadi̇n Çakir
Turkish Journal of Earth Sciences
Detail mapping of active fault zones bounding four travertine masses in the Gediz and Menderes grabens of western Turkey revealed that they are divided into geometric fault segments up to 13 km long. Fissures, supplying the carbonate-rich waters that give rise to the travertines are preferentially developed at the ends of the fault segments or in extensional step-over zones where the offset between the fault strands is about 1 km or more. The deposition of travertines in such structural settings is probably a consequence of the network of fissures supplying the carbonate-rich waters being highly interconnected where extensional strains were …
Fractional Crystallization And Magma Mingling/Mixing Processes In The Monzonitic Association In The Sw Part Of The Composite Yozgat Batholith (Şefaatli-Yerköy, Sw Yozgat), Si̇bel Tatar, Durmuş Boztuğ
Fractional Crystallization And Magma Mingling/Mixing Processes In The Monzonitic Association In The Sw Part Of The Composite Yozgat Batholith (Şefaatli-Yerköy, Sw Yozgat), Si̇bel Tatar, Durmuş Boztuğ
Turkish Journal of Earth Sciences
The Yozgat batholith takes place in the passive margin of the Anatolide-Pontide convergence system. It includes; syn-collisional S-type, two-mica granites; post-collisional I-type, calcalkaline monzonitic association, and post-collisional, M-type, tholeiitic gabbroic/dioritic association. Among these associations, the monzonitic association is also subdivided into five mapable units such as Cankılı monzogabbro/monzodiorite, Akçakoyunlu quartz monzodiorite, Adatepe quartz monzonite, Yassiagil monzogranite and Karakaya monzogranite. All these subunits, except the Karakaya monzogranite, include K-feldspar megacrysts. These five subunits represent some evidence of fractional crystallization (FC) and magma mingling/mixing processes by means of field, mineralogical-petrographical and geochemical characteristics. There is a good zonation in the field that …
Orogenic To Non-Orogenic Magmatic Events: Overview Of The Late Variscan Magmatic Evolution Of The Alpine Belt, Bernard Bonin
Orogenic To Non-Orogenic Magmatic Events: Overview Of The Late Variscan Magmatic Evolution Of The Alpine Belt, Bernard Bonin
Turkish Journal of Earth Sciences
The Alpine belt comprises several pieces of Pre-Mesozoic basement, which have received various imprints of the successive Paleozoic orogenic episodes. If Pre-Mesozoic palinspatic reconstructions are taken into account, the Alpine basement can be considered as one single area before Mesozoic continental breakup. Contrasting magma associations were emplaced according to space and time. There exists a controversy about the existence of the Caledonian orogenic episode. The Lower Paleozoic orogenesis was advocated through different lines of evidences in the southern Alpine basement, such as emplacement of Ordovician and Silurian protoliths of calc-alkaline and alkaline orthogneisses. The Variscan orogenic episode ended with the …
Geochronology And Geochemistry Of Basaltic Rocks In The Karasu Graben Around Kırıkhan (Hatay), S. Turkey, Osman Parlak, Ali̇can Kop, Ulvi̇ Can Ünlügenç, Cavi̇t Demi̇rkol
Geochronology And Geochemistry Of Basaltic Rocks In The Karasu Graben Around Kırıkhan (Hatay), S. Turkey, Osman Parlak, Ali̇can Kop, Ulvi̇ Can Ünlügenç, Cavi̇t Demi̇rkol
Turkish Journal of Earth Sciences
The study area, which is located in the middle sector of the Amanos mountains, covers the north of Kırıkhan (Hatay) in southern Turkey. Tectonostratigraphic rock units from Paleozoic to Cenozoic are exposed within this terrain, which is tectonically active as a result of continent-continent collision between Afro-Arabia and Eurasia. Young basaltic volcanism, located at the N-end of the Dead Sea transform fault in southern Turkey, crops out along the NE-SW trending structural lineaments within the Karasu valley (Hatay). K.Ar age determinations performed on the volcanic rocks give an age range from 0.4 Ma to 2.2 Ma that indicate Plio-Quaternary time …
Miocene Synvolcanic Alluvial Sedimentation In Lignite-Bearing Soma Basin, Western Turkey, Uğur İnci̇
Miocene Synvolcanic Alluvial Sedimentation In Lignite-Bearing Soma Basin, Western Turkey, Uğur İnci̇
Turkish Journal of Earth Sciences
Calcalkaline volcanism and volcaniclastic deposition controlled considerable mode of late Miocene sedimentation and basinal development of the lignite-bearing Soma basin in western Turkey. The volcanism-induced Denis Formation, overlying the Soma Formation discordantly, is represented by two rock assemblages: 1) In the depositional axis of the basin, green, fine-grained sandstone dominated alluvial-lacustrine deposits and, 2) In the northern margin of te basin, syn-eruptive volcaniclastic apron deposits which are mainly composed of fine and coarse-grained volcaniclastic/pyroclastic rocks and lavas. The primary volcanic rocks surrounding probably low-relief volcanoes representing near-vent assemblage are composed mainly of andesitic, rhyolitic and basaltic lavas and pyroclastics. These …