Mehmet Keskin

Mehmet Keskin
Istanbul Technical University ·  Department of Geological Engineering

Doctor of Philosophy

About

91
Publications
32,647
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,618
Citations
Introduction
Petrology and geochemistry of igneous rocks; collision, extension, subduction related and intraplate volcanism across Anatolia and surrounding regions; volcanism. Petrologic modelling of magmatic processes.
Additional affiliations
October 2019 - March 2021
Istanbul Technical University
Position
  • Professor (Full)
December 2014 - October 2019
Istanbul University
Position
  • Professor

Publications

Publications (91)
Article
Full-text available
In many ancient and active volcanic provinces, dyke systems are commonly disposed radially and concentrically around the volcanic chimney, represented by a central intrusive body in many eroded examples. In Istanbul, NW Turkey, late Cretaceous dykes, which are emplaced into the pre-Cretaceous basement consisting of sedimentary rocks of Palaeozoic a...
Conference Paper
Full-text available
مجموعه آتشفشانی سهند بخشی از سنگهای پلیوکواترنر نوار ماگمایی ارومیه دختر ایران مرکزی است که درجنوب استان آذربایجان شرقی قرار دارد این مجموعه از سنگهای ولکانیک و پیروکلاستیک تشکیل شده است که با مرز دگرشیب برروی واحدهای رسوبی با سن میوسن قرار دارند عمده سنگهای این توده ولکانیک از جنس ریولیت و داسیت می باشند این سنگهای پیروکلاستیک دارای آنکلاوهای تیره...
Conference Paper
Full-text available
‫ Sahand volcanic complex is a part of Plio-Quaternary Uromieh-Dohtar Magmatic Belt Lying in the South of East-Azarbijan province. It consists of volcanic and pyroclastic rocks that unconformably cover the Miocene sedimentary formations. The Lithology of These rocks mainly dacite and rhyolite. The studied pyroclastic rocks have dark and rounded enc...
Conference Paper
Full-text available
Around Karapınar, in the south of the Central Anatolian Volcanic Province, a young volcanic assemblage consisting of maars, scoria cones and related volcanics called the Meke volcanics is exposed. It covers an area of 42 km 2 and consist of base-surge and scoria deposits with volcanic bombs, pyroclastic fall/flow products, volcanoclastic layers and...
Conference Paper
Full-text available
The Erzurum-Kars Volcanic Plateau (EKVP) was formed by volcanic eruptions during the Messinian- Zanclean (~5.5 Ma) period, related to a continental collision event between Eurasia and Arabia, initiated ~15 Ma ago. The EKVP unconformably overlies a series of older sedimentary formations spanning in age from Cretaceous to Miocene. It starts with a ~4...
Conference Paper
Full-text available
The study area is located on the southern edge of the Erzurum-Kars Volcanic Plateau (EKVP). This part of the plateau is known to have been formed by the eruptions during the Zanclean (~4.5 Ma) period, related an earlier continental collision event between Eurasian and Arabian continents ~15 Ma ago. The EKVP is composed mainly of andesitic and dacit...
Conference Paper
Full-text available
Havran, Çakırdere ve Çakmak (Balıkesir) arasında kalan çalışma alanının kuzeyinde ve kuzeydoğusunda Kazdağı Metamorfik Masifi ve onunla ilişkili metamorfik birimler yüzeylenmektedir. Arazinin güneyinde ise, Menderes Masifi'nin bir devamı niteliğinde metamorfik temel birimleri mostra vermektedir. Sözü geçen iki temel metamorfik birim, Oligosen-Miyos...
Article
Collision-related Quaternary mafic volcanism to the north of Lake Van (Eastern Anatolia, Turkey) occurred by eruptions from both volcanic centres and extensional fissures trending approximately north–south. We report new major, trace and rare earth element abundances, Sr–Nd–Pb isotope ratios and K–Ar ages for basaltic and more evolved hawaiitic and...
Article
The Western Pontide Magmatic Belt consists of two different magmatic series corresponding to two distinct periods of intense volcanism, separated by a pelagic limestone marker horizon resting on a regional unconformity. The first stage of magmatism and associated extensional tectonic regime prevailed in the region between the Middle Turonian and Ea...
Article
Full-text available
We report new U–Pb zircon ages, major and trace element data, mineral chemistry, and Sr–Nd isotopic analyses of the mafic–intermediate dykes and intrusions in the İstanbul Zone. Mafic dykes are represented by calc-alkaline to alkaline lamprophyre and diabase. Intermediate dykes and subvolcanics are andesitic to dacitic in composition and calc-alkal...
Conference Paper
Full-text available
Between the towns of Sarıkamı¸sSarıkamı¸s and Kagızman, NE Turkey, a medium-sized strato-volcano with satellite cones and domes on its slopes unconformably overlies the Erzurum-Kars Volcanic Plateau (EKVP) with a subhorizontal contact. It is called the Alada˘ g volcanic system (AVS). Dating results indicate that the AVS is Pliocene in age. The EKVP...
Chapter
We report new U-Pb zircon ages, major and trace element data, mineral chemistry and Sr–Nd isotopic analyses of the mafic – intermediate dykes and intrusions in the İstanbul zone. Mafic dykes are represented by calc-alkaline to alkaline lamprophyre and diabase. Intermediate dykes and sub-volcanics are andesitic to dacitic in composition and calc-alk...
Conference Paper
Full-text available
Stratigraphic evidence from the Murat region (Mus-Van basins) suggests that the east Anatolian plateau emerged from below sea level ~ 13-15 Ma. The plateau stands at 2 km average elevation today and is underlain by hot/buoyant asthenospheric mantle rather than thick lithosphere. The voluminous melt production/magmatism during the last 13 Myrs is in...
Article
Full-text available
The series of two papers presents a comprehensive isotope-geochronological and petrological- geochemical study of the Late Quaternary Tendürek Volcano (Eastern Turkey), one of the greatest volcanoes within the Caucasian–Eastern Anatolian segment of the Alpine foldbelt. The second article discusses the results of petrogenetic modeling, role of AFC-p...
Conference Paper
Full-text available
Basement of the study area is represented by the Kırşehir Massif, which is one of important metamorphic massifs in Turkey. This metamorphic basement is unconformably overlain by clastic sediments which were deposited in Paleogene basins and then heavily deformed due to the closure of the Neotethys Ocean in the North. Paleogene deposits are, in turn...
Conference Paper
Full-text available
The east Anatolian orogenic plateau is characterized by an average elevation of 2 km, and is delimited by the Bitlis-Zagros collision zone to the south and the Pontide arc to the north. Stratigraphic evidence suggests that the high plateau attained its current elevation since the Serravallian (about 12 million years ago), but probably did not reach...
Article
The Pliocene Etrüsk stratovolcano, located in the northeast of Lake Van (Eastern Anatolia; Turkey), is one of the important volcanic centres in the Eastern Anatolian collision zone. Mt. Etrüsk overlies a widespread volcanic plateau, consisting of basaltic and hawaiitic lavas formed by fissure eruptions between 4.9–4.5 Ma. These basic lavas contain...
Data
Simplified version of the Tendürek Volcano map. Compiled by V.A. Lebedev, 2016©. Appendix A to the paper Lebedev V.A. et al., 2016a //Petrology, 24(2), 127-152. Please, remember about copyrights and references!
Data
3D version (with orography) of the Tendürek Volcano map. Compiled by V.A. Lebedev, 2016©. Appendix B to the paper Lebedev V.A. et al., 2016a //Petrology, 24(2), 127-152. Please, remember about copyrights and references!
Data
Multilayer (original) version of the Tendürek Volcano map. Scale 1/100000. Compiled by V.A. Lebedev, 2016©. Layers: topography, geology, sampling points, K-Ar datings Appendix C to the paper Lebedev V.A. et al., 2016a //Petrology, 24(2), 127-152. Please, remember about copyrights and references!
Article
Full-text available
The series of two papers presents a comprehensive isotope-geochronological and petrological-geochemical study of the Late Quaternary Tendürek Volcano (Eastern Turkey), one of the greatest volcanoes within the Caucasian—Eastern Anatolian segment of the Alpine foldbelt. The first article discusses the results of chronostratigraphic reconstruction and...
Article
Full-text available
Palaeomagnetic studies of the Neogene–Quaternary rocks of Anatolia have been mostly interpreted in the light of its westward escape as a result of the collision between the Arabian and Eurasian plates along the Bitlis–Zağros suture during the Neotectonic period. However, within the collision zone, in East Anatolia, palaeomagnetic data are not avail...
Conference Paper
Full-text available
The Eastern Anatolia region (with an average ∼2 km elevation) is dominated by N-S shortening and it represents one of the best examples for active/young continental collision between the Arabian and Eurasian plates. Studies suggest that the entire plateau began to rise since the plate collision (about 13 Ma) along the Bitlis-Zagros suture zone and...
Article
Magmatic arcs are zones of high heat flow; however, examples of metamorphic belts formed under magmatic arcs are rare. In the Pontides in northern Turkey, along the southern active margin of Eurasia, high temperature–low pressure metamorphic rocks and associated magmatic rocks are interpreted to have formed under a Jurassic continental magmatic arc...
Article
Full-text available
Abstract One of the pre-Jurassic metamorphic basements of the Western Sakarya Zone (NW Turkey) is the Havran Unit which contains meta-sedimentary (i.e. the Kalabak formation) and meta-intrusive rocks of Devonian in age. A LA-ICP-MS U-Pb zircon dating study was conducted on 125 zircon grains obtained from a meta-sedimentary rock to better understan...
Conference Paper
Full-text available
The Quaternary Tendürek Volcano is one of the largest eruption centers of the Eastern Anatolia with a summit elevation of 3538 m and a footprint area of 650 km2. It is a shield volcano consisting of lavas ranging in composition from tephrites through benmoreites/phonolites to trachytes. The young volcanism of the region is thought to be related to...
Article
Full-text available
Quaternary mafic lavas in the north of Lake Van erupted not only from eruption center like Girekol miniature shield volcano but also from N-S (Yüksektepe volcanic field) and E-W (Ormuktepe volcanic field) extending extensional fractures. Literature K/Ar dates (Lebedev et al., 2010) indicate that the basaltic and hawaiitic lavas erupted in a period...
Article
Full-text available
AFC-Modeler is a user-friendly, interactive Microsoft Excel workbook program which is specifically designed to model up to ten theoretical AFC curves (corresponding to ten different r values; r being the ratio of mass assimilation rate to fractional crystallization rate) for a set of variables that can be interactively and precisely modified by the...
Article
Full-text available
This paper considers results from isotope-geochronological (K-Ar) studies of the products of Neogene-Quaternary volcanism in the Karacadağ area, which is situated within the northern frontal part of the Arabian plate. It was found that magmatic activity has been evolving at this location for at least the last 11–10 Myr and was distinctly discrete i...
Article
Full-text available
A geochemical and isotope-geochemical (Sr-Nd-Pb) study has been carried out for the Karacadağ neovolcanic area, which is situated within the frontal part of the Arabian plate. The obtained data and the results of petrological modeling show that the petrogenesis of parental magmas in the Karacadağ neovolcanic area involved two compositionally differ...
Article
Full-text available
Middle Eocene magmatic rocks (MEMR) (49.3 +/- 2 to 38.1 +/- 1.9 Ma) formed an east-west trending belt after continental collision and rest unconformably on pre-Middle Eocene units as a common cover. The origin and tectonic setting of MEMR are controversial as both arc and post-collisional settings are proposed. We present new geological and petrolo...
Conference Paper
Full-text available
One of the best transects of the Erzurum-Kars Volcanic Plateau (EKVP) is exposed along the River Kura canyon in the north of the town of ÇÕldÕr (Ardahan) close to the state border with Georgia. There are over 20 lava and pyroclastic units on the walls of the Kura canyon, which reaches in depth up to 700 m in places. MTA's reports indicate that this...
Conference Paper
Full-text available
Eastern Turkey has been an active continental collision zone for the last 15 My between the African and Eurasian continents. The collision started at around 15 Ma after the total consumption of oceanic lithosphere of the southern branch of the Neotethys Ocean beneath E Anatolia and is still going on, as Africa still converges to E Anatolia with a v...
Article
Full-text available
The volcanic activity of Mt. Karacadağ (SE Anatolia) is divided into three major stages: Siverek Stage (∼11–2.7 Ma), Karacadağ Stage (∼1.9–1.0 Ma) and Ovabağ Stage (0.4–0.01 Ma). The magmas are mildly alkaline mafic rocks, mostly basanites, hawaiites and alkali basalts. Detailed geochemical investigation indicates a continuous variation of composit...
Article
A unique example of isotopically-dated Devonian metagranitoid (the Çamlık metagranite; Okay et al., 1996) crops out in the Biga Peninsula, NW Turkey, although its contact relationships with the country rocks and geodynamic setting have remained to be enigmatic so far. Our field work, however, has shown that a number of metagranitoid bodies similar...
Article
Full-text available
در منطقه سهند در بخش شمالی نوار آتشاشانی اروميه- دختر، گنبدهاي آداکيتی پرسيليا متعددي با ترکيب ريوليت، داسيت، تراکی داسيت، تراکی آنگدزيت و آندزيت، متعلق به محدوده زمانی ائوسن پ ين تا پليوسن وجود دارد که سنگ هاي آتشاشانی- رسگوبی ائوسگن و نيگ در برخگی مگوارد سگنگ هگاي رسگوبی اليگوسن- ميوسن را قطع کرده اند و تکه هايی از آنها را به صورع بيگانه سنگ در ب...
Conference Paper
Full-text available
ABSTRACT Post collisional volcanic rocks cover large areas in the east of the Biga peninsula, which is located in the NW Anatolian magmatic belt along the southern margin of Marmara Sea. These volcanic units span a compositional range from calc-akaline (i.e. andesite, dacite, and rhyodacite to rhyolite), to alkaline (olivine basalts) lavas. All ro...
Article
Full-text available
Volcanic activity at Mt. Karacada˘ g, SE Turkey, developed between $11 and $0.01 Ma. In this paper we investigate the oldest products (older than 2.6 Ma) that created a large volcanic plateau and a N-S aligned volcanic edifice in the form of a shield volcano. These igneous rocks are mildly alkaline to transitional olivine-clinopyroxene phyric basal...
Article
Full-text available
An isotope-geochronological study has been performed to examine the products of Late Cenozoic collision volcanism on the northern coast of Lake Van, Turkey. We obtained 45 new K-Ar dates, based on which the principal time characteristics of volcanic activity in the region have been determined. Volcanic activity in the northern coast of Lake Van has...
Conference Paper
Full-text available
The region including the Eastern Anatolian - Northern Iranian High Plateau and Greater and Lesser Caucasus mountain ranges is one of the best examples of an active continental collision zone in the world, which is thought to have been formed by the closure of the northern branch of the Neotethyan Ocean. It comprises one of the high plateaus of the...
Article
Full-text available
An isotope-geochronological study has been performed to examine the products of Late Cenozoic collision volcanism on the northern coast of Van Lake, Turkey. We obtained 45 new K-Ar dates, based on which the principal time characteristics of volcanic activity in the region have been determined. The total duration of magmatic activity in the area of...
Data
Multi-layer geological map of Northern Van neovolcanic area (Eastern Anatolia, Turkey), the region with a large manifestation of Neogene-Quaternary volcanism. Scale 1/100000. Compiled by V.A. Lebedev (IGEM RAS) ©. File is in PSD (Photoshop) format. Layers: topography, Google image, geology, sampling points and K-Ar ages. The map will be updated con...
Conference Paper
Full-text available
The Pliocene Etrusk volcano, with its 3100 m elevation and ~500 km2 area, is one of the major centers of the collision-related volcanism in E Anatolia. It is located in the northeast of Lake Van, sitting almost on the culmination of the "Lake Van dome" structure forming the vertex of the eastern Turkish high plateau (Sengor et al., 2008). A ~5-km-w...