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Full-Text Articles in Physical Sciences and Mathematics

Geochemistry Of The Lake Sediments On Robert Island, South Shetland Islands, Antarctica: Implications For Weathering Processes In Polar Areas, Merve Özyurt, Yilmaz Demi̇r, Korhan Özkan, Rai̇f Kandemi̇r Nov 2023

Geochemistry Of The Lake Sediments On Robert Island, South Shetland Islands, Antarctica: Implications For Weathering Processes In Polar Areas, Merve Özyurt, Yilmaz Demi̇r, Korhan Özkan, Rai̇f Kandemi̇r

Turkish Journal of Earth Sciences

The preliminary results of geochemical analyses of the surface sediments from 4 lakes on Robert Island, South Shetland, Antarctica, are presented herein. The samples were collected during the Turkish Antarctic Expedition (TAE-II) in 2018. Sediment samples were obtained from the littoral zone (approximately 20 cm) of 4 different lakes exposed on the glacier-free land area on Robert Island. The lake sediments predominantly consist of fine-grained sand, clay, and silt particles. These particles include Fe-shale and graywacke geochemical characteristics. Their plagioclase index of alteration, chemical index of weathering, chemical index of alteration, and other weathering index values, suggest that the studied …


Accuracy Investigation Of Gnss-Reflectometry For Sea Level Monitoring On Horseshoe Island, Antarctica: Preliminary Results Of The Turkish Permanent Gnss Station (Tur1), Mahmut Oğuz Selbesoğlu, Hasan Hakan Yavaşoğlu, Mustafa Fahri̇ Karabulut, Özgün Oktar, Vahap Engi̇n Gülal, Hi̇mmet Karaman, Mustafa Ersel Kamaşak Nov 2023

Accuracy Investigation Of Gnss-Reflectometry For Sea Level Monitoring On Horseshoe Island, Antarctica: Preliminary Results Of The Turkish Permanent Gnss Station (Tur1), Mahmut Oğuz Selbesoğlu, Hasan Hakan Yavaşoğlu, Mustafa Fahri̇ Karabulut, Özgün Oktar, Vahap Engi̇n Gülal, Hi̇mmet Karaman, Mustafa Ersel Kamaşak

Turkish Journal of Earth Sciences

Antarctica is called a natural laboratory and is highly important for investigating climate change and its evolution over time. Sustainability is a critical concern due to the challenges posed by glacier melting and rising sea levels due to global warming. According to the Intergovernmental Panel on Climate Change, since the industrial age, the global mean sea level has risen by about 20 cm as a result of the increase in the average world temperature by 1 °C. Therefore, long-term observations by satellite-based techniques in and around Antarctica are of great importance for monitoring the impacts of climate change. In the …


Applicability Of Real-Time Ppp Technique In Polar Regions As An Accurate And Efficient Real-Time Positioning System, Reha Meti̇n Alkan, Serdar Erol, Bi̇lal Mutlu Nov 2023

Applicability Of Real-Time Ppp Technique In Polar Regions As An Accurate And Efficient Real-Time Positioning System, Reha Meti̇n Alkan, Serdar Erol, Bi̇lal Mutlu

Turkish Journal of Earth Sciences

The polar regions, which include the Arctic and Antarctic areas, attract the attention of people every day, and issues that are closely related to the future of humanity make these regions even more important. Accurate and reliable positioning in polar regions is very critical for scientific research projects and also for commercial, touristic, and other human activities. In this study, the usability and the accuracy performance of the real-time precise point positioning (RT-PPP) technique in high-latitude polar regions with harsh environmental and extreme atmospheric conditions were investigated. Within that framework, the GNSS dataset of six IGS multi-GNSS stations located at …


The Petrogenesis Of Analcime In The Coppermine Formation On Robert Island, South Shetland Islands, Antarctica, Rai̇f Kandemi̇r, Yilmaz Demi̇r, Cüneyt Şen, Ufuk Celal Yağcioğlu Nov 2023

The Petrogenesis Of Analcime In The Coppermine Formation On Robert Island, South Shetland Islands, Antarctica, Rai̇f Kandemi̇r, Yilmaz Demi̇r, Cüneyt Şen, Ufuk Celal Yağcioğlu

Turkish Journal of Earth Sciences

The South Shetland Islands were shaped by island arc volcanism that occurred from the Jurassic to the Quaternary. Robert Island is located in the center of this archipelago, and Coppermine Peninsula, located on the southwestern part of Robert Island, exposures significant rock outcrops of basalts and andesitic-basaltic agglomerates of the Coppermine Formation. The investigated samples were collected during Turkish Antarctic Expedition 2 (TAE-II), in March-April 2018, from the area northeast of Triplet Hill. The volcanic rocks exhibited an amygdaloidal microlithic-porphyritic texture. Subhedral to anhedral phenocrysts of labradorite, augite, and olivine were observed with holocrystalline groundmass composed of plagioclase, pyroxene, and …


Webgis-Based Data Center Design For Polar Science Studies: Simulation Of Türkiye, Müge Şenel, Hasan Hakan Yavaşoğlu, Burcu Özsoy, Hi̇mmet Karaman, Mustafa Ümi̇t Gümüşay Nov 2023

Webgis-Based Data Center Design For Polar Science Studies: Simulation Of Türkiye, Müge Şenel, Hasan Hakan Yavaşoğlu, Burcu Özsoy, Hi̇mmet Karaman, Mustafa Ümi̇t Gümüşay

Turkish Journal of Earth Sciences

Scientific studies concentrated in Antarctica hold great value and importance for humanity. Research projects are conducted in various disciplines on the continent, where nearly 100 research stations from 30 countries are established. Despite the challenges posed by Antarctica's natural structure, unique environment, difficult working conditions, and limited logistics opportunities, scientific research conducted there is indispensable due to the valuable information it offers. In pursuit of accessing this information, Turkish Antarctic expeditions have been organized since 2017. In this study, a polar data center was established through a web-based geographic information system (WebGIS), a significant infrastructure for the continuity of scientific …


Exploring Crowdsourcing Accountability For Mapping Antarctica: A Case Study Using 5 Years Of Social Media Data, Ayşe Gi̇z Gülnerman Gengeç Nov 2023

Exploring Crowdsourcing Accountability For Mapping Antarctica: A Case Study Using 5 Years Of Social Media Data, Ayşe Gi̇z Gülnerman Gengeç

Turkish Journal of Earth Sciences

The continent of Antarctica is one of the most challenging regions in terms of generating and updating geodata. Extensive research has been conducted on geodata acquisition, primarily focusing on earth observation satellites and local surveys in polar regions. Earth observation satellites offer limited spatial, temporal, and semantic data, while local surveys are constrained by polar regions' size and challenging conditions. This article delves into the crowdsourced data, aiming to significantly enhance geodata contribution in polar regions beyond current methods. To our knowledge, this study is the first of its kind to address social media data, a form of crowdsourcing, specifically …


Water Chemistry And Pigment Composition Of 13 Lakes And Ponds In Maritime Antarctica, Korhan Özkan Nov 2023

Water Chemistry And Pigment Composition Of 13 Lakes And Ponds In Maritime Antarctica, Korhan Özkan

Turkish Journal of Earth Sciences

The Antarctic Peninsula has been rapidly warming, resulting in changes to the abundance and surface cover of terrestrial aquatic ecosystems, as well as their ecosystem structure and function. Therefore, comparative studies of aquatic ecosystems across large latitudinal gradients can be useful in better understanding these changes and making more reliable predictions regarding the consequences of climate change. During Turkish Antarctic Expeditions in 2018 and 2019, samples were collected from 10 lakes and 3 ponds across Maritime Antarctica (north-western coasts of the Antarctic Peninsula). These lakes and ponds were located on Ardley, Robert, Livingstone, Galindez, and Horseshoe islands, covering a latitudinal …


Accuracy Assessment Of Glacier Depth Monitoring Based On Uav-Gpr On Horseshoe Island, Antarctica, Mahmut Oğuz Selbesoğlu, Mustafa Fahri̇ Karabulut, Özgün Oktar, Burak Akpinar, Oleg Vassilev, Mehmet Arkali, Şeyma Nur Tufan, Alptuğ Şeref Ayyildiz, Esra Günaydin, Ati̇lla Yilmaz, Doğaç Baybars Işiler, Burcu Özsoy Nov 2023

Accuracy Assessment Of Glacier Depth Monitoring Based On Uav-Gpr On Horseshoe Island, Antarctica, Mahmut Oğuz Selbesoğlu, Mustafa Fahri̇ Karabulut, Özgün Oktar, Burak Akpinar, Oleg Vassilev, Mehmet Arkali, Şeyma Nur Tufan, Alptuğ Şeref Ayyildiz, Esra Günaydin, Ati̇lla Yilmaz, Doğaç Baybars Işiler, Burcu Özsoy

Turkish Journal of Earth Sciences

Unmanned aerial systems have a wide range of uses in studying the impacts of climate change over several fields. Recently, its combination with a ground-penetrating radar (GPR) technology has been demonstrated to be highly effective for surveying glaciers, especially in difficult and inaccessible terrains like Antarctica. In this context, this study focused on exploring the potential of using an unmanned aerial vehicle (UAV)-GPR to measure the depth of glaciers on Horseshoe Island, West Antarctica. The data were collected during the seventh Turkish Antarctic Expedition (TAE-VII) in February and March 2023, within the scope of the international project titled "Glacier monitoring …


The Geo/Thermochronology Of Dismal Island (Marguerite Bay, Antarctic Peninsula), Fati̇h Karaoğlan, Burcu Karataş, Yavuz Özdemi̇r, Erhan Gülyüz, Oleg Vassilev, Mahmut Oğuz Selbesoğlu, Semi̇h Gi̇ldi̇r Nov 2023

The Geo/Thermochronology Of Dismal Island (Marguerite Bay, Antarctic Peninsula), Fati̇h Karaoğlan, Burcu Karataş, Yavuz Özdemi̇r, Erhan Gülyüz, Oleg Vassilev, Mahmut Oğuz Selbesoğlu, Semi̇h Gi̇ldi̇r

Turkish Journal of Earth Sciences

Dismal Island is located at the entrance of Marguerite Bay between Adelaide Island to the northeast and Alexander Island to the southwest within the Antarctic Peninsula (AP). Its unique position between Alexander and Adelaide islands provides the opportunity to perform testing and link these regions through Cenozoic magmatism and tectonics due to the subduction of the Pacific plate beneath the AP along the northern margin. Dismal Island was visited in February 2021 within the framework of the sixth Turkish Antarctic Expedition (TAE-VI). Thirteen samples were collected for petrography, geochronology, and low-temperature thermochronology (LTT). Of the samples, 3 were dated using …


Almacık Complex-An Exhumed Lower To Middle Crust In Northwest Anatolia, Aral Okay, Andrew R.C. Kylander-Clark, Sarah Sherlock Nov 2023

Almacık Complex-An Exhumed Lower To Middle Crust In Northwest Anatolia, Aral Okay, Andrew R.C. Kylander-Clark, Sarah Sherlock

Turkish Journal of Earth Sciences

The Almacık Complex is a tectonic unit of high-grade metamorphic rocks in the Intra-Pontide Suture Zone in northwest Turkey. It consists mainly of amphibolite, metaultramafic rock, and gneiss, which are intruded by numerous pre-, syn-, and posttectonic felsic veins. The Almacık Complex is variously interpreted as a Cretaceous or Neoproterozoic ophiolite, or a Permian mafic-ultramafic complex representing the middle to lower crust of the Sakarya Zone. Herein, new petrological and geochronological data were presented from the Almacık Complex. Two-pyroxene geothermometry in the metawebsterites indicated that the Almacık Complex has undergone upper amphibolite-facies metamorphism at 750 ± 30 °C and 8 …


More Evidence Of Tropical Conditions In The Middle Eocene Climatic Optimum (Meco) With New Fossil Woods From North-Central Türkiye, Ünal Akkemi̇k, Fi̇kret Koçbulut, Özlem Toprak, Umut Tunç Nov 2023

More Evidence Of Tropical Conditions In The Middle Eocene Climatic Optimum (Meco) With New Fossil Woods From North-Central Türkiye, Ünal Akkemi̇k, Fi̇kret Koçbulut, Özlem Toprak, Umut Tunç

Turkish Journal of Earth Sciences

Fossil wood descriptions are among the most important indicators in understanding forest structures across geological ages. This study was carried out to obtain new findings about the Middle Eocene Climate Optimum (MECO) period of Anatolia with new samples collected from the Middle Eocene-aged fossil area near Amasya-Göynücek. The fossil area falls into the Göynücek Volcanics in the region. Transverse, radial, and tangential microscopic sections were taken from three new fossil wood samples, and all identifications were performed on these microscopic sections. As a result, the fossil species were identified as Pinuxylon cf. P. tarnocziense, cf. Dichrostachyoxylon zirkelii, and Laurinoxylon perseamimatus …


Middle Eocene Alveolina-Dominated Benthic Foraminiferal Assemblages Of The Western Flank Of The Isparta Angle (Sw Türkiye): Taxonomy, Biostratigraphy, Microfacies Analysis, And Paleoenvironmental Implications, Alper Bozkurt, Muhi̇tti̇n Görmüş, Banu Türkmen Bozkurt Nov 2023

Middle Eocene Alveolina-Dominated Benthic Foraminiferal Assemblages Of The Western Flank Of The Isparta Angle (Sw Türkiye): Taxonomy, Biostratigraphy, Microfacies Analysis, And Paleoenvironmental Implications, Alper Bozkurt, Muhi̇tti̇n Görmüş, Banu Türkmen Bozkurt

Turkish Journal of Earth Sciences

Middle Eocene formations of the western part of the Isparta Angle contain abundant larger benthic foraminifera (LBF). Twelve species belonging to the genus Alveolina, including A. callosa, A. fragilis, A. aff. fusiformis, A. gigantea, A. cf. gigantea, A. hottingeri, A. kieli, A. levantina, A. nuttalli, A. cf. obtusa, A. stipes, and A. tenuis have been identified throughout the two measured sections from Dinar and Çardak (SW Türkiye). The investigated assemblages, consisting also of nummulitids, orthophragminids, textulariids, rotaliids, and miliolids, allow us to assign the Suçıkan section to shallow benthic zone 13 (SBZ13) and the Karabayır section to SBZ17. Based on …


Mapping Crustal Structure And Deformation Using Gravity Data In The Bursa Basin And Surroundings, Türkiye, Bülent Oruç, Emi̇r Balkan Nov 2023

Mapping Crustal Structure And Deformation Using Gravity Data In The Bursa Basin And Surroundings, Türkiye, Bülent Oruç, Emi̇r Balkan

Turkish Journal of Earth Sciences

The structure and deformation of the Bursa Basin and surroundings was carried out through the interpretation of Bouguer gravity and isostatic residual gravity anomalies. The spectral analysis was carried out on Bouguer anomalies to obtain the average depths of the crustal structure under the Bursa Basin and surroundings. Parker-Oldenburg algorithm was used to estimate the depths of the interface between upper and lower crust with respect to an average depth and density contrast. We used Mallick-Sharma algorithm to separate the regional gravity anomalies from Bouguer anomalies to estimate the isostatic residual gravity anomalies. Euler deconvolution and two-dimensional density contrast distribution …


Interpreting Structural Configuration Of The Sengkang Basin Of Indonesia Using Edge Detection And 3-D Euler Deconvolution To Satellite Gravity Data, Jamhir Safani, Khalil Ibrahim, Wa Deni, Al Rubaiyn, Firdaus Firdaus, Harisma Harisma Nov 2023

Interpreting Structural Configuration Of The Sengkang Basin Of Indonesia Using Edge Detection And 3-D Euler Deconvolution To Satellite Gravity Data, Jamhir Safani, Khalil Ibrahim, Wa Deni, Al Rubaiyn, Firdaus Firdaus, Harisma Harisma

Turkish Journal of Earth Sciences

The East Walanae Fault Zone and the West Walanae Fault Zone are the two active fault segments in the south arm of Sulawesi. These fault segments are responsible for the formation of the Sengkang Basin. This geological complexity makes the Sengkang Basin a very interesting area to study. This research aims to (1) identify basin boundaries and lithological contacts; (2) estimate the positions of fault segments; and (3) model the basement beneath the Sengkang Basin. The free-air gravity anomaly from the GGMPlus dataset is employed and then corrected using Bouguer and terrain corrections to provide the complete Bouguer gravity anomaly …


A Study On The Magnetite Skarn Mineralization (Gümüşhane, Türkiye): A Magnetic Survey, Ferkan Si̇pahi̇, Münür Burhan Sadiklar, Mehmet Ali̇ Gücer, Ali̇ Aydin, Rasi̇m Taylan Kara Nov 2023

A Study On The Magnetite Skarn Mineralization (Gümüşhane, Türkiye): A Magnetic Survey, Ferkan Si̇pahi̇, Münür Burhan Sadiklar, Mehmet Ali̇ Gücer, Ali̇ Aydin, Rasi̇m Taylan Kara

Turkish Journal of Earth Sciences

Iron (Fe)-skarn mineralizations (Çambaşı, Dereli, Eğrikar, Karadağ, Kopuz, Sekü, Donguldere, Arnastal, Özdil, Ögene, İkizdere, Ovit Dağı, Kartiba, etc.) in the eastern part of the Pontides (NE Türkiye) are accommodated in the Pontide paleomagmatic arc and the eastern part of the Pontides Metallogenic Belt containing numerous various deposits. Fe-skarn mineralization around the Arnastal Plateau (Gümüşhane-Türkiye) is fragmentary in this area, which is covered with plants (grasses, flowers, etc.). Thus, it was attempted to describe the subsurface structures and Fe mineralization using an interpretation of the available geological and existing magnetic data in this area. Granitoid and volcano-sedimentary series (Upper Cretaceous) outcrop …


A Review Of The Geothermal System Evolution And Distribution In The Central Anatolian Crystalline Complex (Türkiye), Mehmet Furkan Şener, Muhammed Zeynel Öztürk, Alper Baba Sep 2023

A Review Of The Geothermal System Evolution And Distribution In The Central Anatolian Crystalline Complex (Türkiye), Mehmet Furkan Şener, Muhammed Zeynel Öztürk, Alper Baba

Turkish Journal of Earth Sciences

Türkiye is located in the Mediterranean sector of the Alpine-Himalayan tectonic belt and is among the foremost seven countries in the world having an abundance of geothermal resources. The Central Anatolian Crystalline Complex (CACC) is one of the most important geothermal regions in Türkiye. This study aims to evaluate the geothermal system of CACC using the geological, structural, and hydrogeochemical properties that were obtained from previous studies. The present study investigated and evaluated the hydrogeochemical and isotopic properties of 762 water samples belonging to 45 different localities from 41 scientific studies. The result shows that CACC has different heat sources …


Zircon Grain Shape Parameters From Ignimbrites Of The Central Anatolian Volcanic Province (Cavp) With Implications For Petrogenetic Processes, Lütfi̇ye Akin Sep 2023

Zircon Grain Shape Parameters From Ignimbrites Of The Central Anatolian Volcanic Province (Cavp) With Implications For Petrogenetic Processes, Lütfi̇ye Akin

Turkish Journal of Earth Sciences

Zircon morphology parameters reflect the physicochemical conditions during crystallization and can be modified by different processes. Zircon populations from Miocene-Pliocene ignimbrites of the Central Anatolian Volcanic Province (CAVP) were studied to reveal relations between the external morphology of zircons and petrogenetic processes. Descriptive grain shape parameters (e.g., minor and major axes, area, perimeter, aspect ratio, roundness, and circularity) were automatically measured from transmitted light images of zircons by a graphical application called AnalyZr. Principal component and cluster analysis were used to determine potential shape descriptors (perimeter, major and minor axis length, and maximum and minimum Feret) for characterizing grains from …


Isotope And Hydrochemical Characteristics Of Thermal Waters Along The Active Fault Zone (Erzin-Hatay/Turkey) And Their Geothermal Potential, Di̇dem Yasi̇n, Gali̇p Yüce Sep 2023

Isotope And Hydrochemical Characteristics Of Thermal Waters Along The Active Fault Zone (Erzin-Hatay/Turkey) And Their Geothermal Potential, Di̇dem Yasi̇n, Gali̇p Yüce

Turkish Journal of Earth Sciences

Geochemical investigations carried out on thermal waters over the Erzin-Hatay area allowed the collection of a suite of 9 samples from natural springs and one well characterized by outlet temperatures in the range from 19.6 to 31.5 °C. All of the springs have slightly acidic pH (in the range of 6) but one sample was marked by a pH value >11 as a consequence of serpentinization processes. The water chemistry denotes water/rock interactions with either magmatic or carbonatic rocks in a water reservoir equilibrated at temperatures estimated to be in the range of 58-162 °C. The stable isotope composition of …


Mineralogical-Petrographical Features, Geochemical Characteristics, And S Isotope Variability Of Pb-Zn Deposits In The Sakarya Fragment Of The Biga Peninsula (Nw Türkiye), Gökhan Demi̇rela, Si̇nan Akiska, Eli̇f Akiska Sep 2023

Mineralogical-Petrographical Features, Geochemical Characteristics, And S Isotope Variability Of Pb-Zn Deposits In The Sakarya Fragment Of The Biga Peninsula (Nw Türkiye), Gökhan Demi̇rela, Si̇nan Akiska, Eli̇f Akiska

Turkish Journal of Earth Sciences

The Biga Peninsula in northwestern Anatolia, a part of the Alpine-Himalayan orogenic belt, has a complex geology that was formed following the closure of the northern branch of the Neotethys. Intense volcanism and plutonism in the area from the Eocene to the Middle Miocene period caused several Pb-Zn-Cu±Ag±Au deposits to form. The geometry of the mineralizations is largely made up of polymetallic veins, manto-chimneys, and irregular replacement bodies. Ore-bearing and host rocks in the mineralization zones and the wall rocks outside the mineralization zones were compiled in this study. The most common minerals in the skarn zones are garnet, pyroxene, …


Density Functional Theory Calculations Of Equilibrium Oxygen Isotope Fractionation Between Borate Minerals And Aqueous Fluids, Hai-Zhen Wei, Martin Palmer, Jun-Lin Wang, Shao-Yong Jiang, Simon V. Hohl, Yuan-Feng Zhu, Chun Huan, Miao-Miao Zhang, Yeşi̇m Yücel Öztürk Sep 2023

Density Functional Theory Calculations Of Equilibrium Oxygen Isotope Fractionation Between Borate Minerals And Aqueous Fluids, Hai-Zhen Wei, Martin Palmer, Jun-Lin Wang, Shao-Yong Jiang, Simon V. Hohl, Yuan-Feng Zhu, Chun Huan, Miao-Miao Zhang, Yeşi̇m Yücel Öztürk

Turkish Journal of Earth Sciences

Borax, ulexite, and colemanite minerals are by far the most important economic source of boron and occur almost exclusively in nonmarine evaporite deposits. While much is known about the geological setting in which they are found, surprisingly little is known about the chemical and physical properties of the brines from which they are formed. Oxygen isotope studies have the potential to reveal important new information regarding borate formation, but unlike most other common oxygen-bearing salts precipitated from brines, there are no experimental data regarding the oxygen isotope fractionation factors between borates and brines. As a first attempt to address this …


Rank Of Kozlu Formation Coals In The Zonguldak Basin: Implications For Coalbed Gas, Mehmet Namik Yalçin, Cemi̇l Seyi̇s, Sedat İnan Sep 2023

Rank Of Kozlu Formation Coals In The Zonguldak Basin: Implications For Coalbed Gas, Mehmet Namik Yalçin, Cemi̇l Seyi̇s, Sedat İnan

Turkish Journal of Earth Sciences

Carboniferous bituminous coals of the Zonguldak Basin have been mined for over a century. Due to underground mining activity, there have been several fatal incidents related to gas explosions. The gas content of the coals varies greatly in the basin mainly based on coal maturity (rank), increasing with increasing coal depth. In this study, we report a map for coal depth and coal rank in the Kozlu-Üzülmez-Karadon districts of Zonguldak Basin with hope the that it would aid coal gas exploration/exploitation and also coal gas degassing efforts for safer underground mining production in the Zonguldak Basin.


Dynamics Of A Giant Slow Landslide Complex Along The Coast Of The Aral Sea, Central Asia, Gökhan Aslan, Marcello De Michele, Daniel Raucoules, François Renard, John Dehls, Ivanna Penna, Reginald Hermanns, Zi̇yadi̇n Çakir Sep 2023

Dynamics Of A Giant Slow Landslide Complex Along The Coast Of The Aral Sea, Central Asia, Gökhan Aslan, Marcello De Michele, Daniel Raucoules, François Renard, John Dehls, Ivanna Penna, Reginald Hermanns, Zi̇yadi̇n Çakir

Turkish Journal of Earth Sciences

We report here a slow-moving landslide complex of the lateral spreading type revealed by Sentinel-1 interferometric timeseries analysis. Located along the western coast of the Aral Sea, with a >150-km length and 3-km width, a giant active landslide complex, slides with a constant velocity of up to 60 mm/year. Systematic subsidence up to 5 mm/year is also observed along narrow strips of terraces that appear to result from rotations of fault-bounded blocks. The landslide deformation velocity does not correlate with the annual variations of the water level in the southwestern lake of the Aral Sea during the observation period of …


Use Of Aeromagnetic Data For Structural Mapping Of The Tlemcen Mountains (Northwestern Algeria), Lahcen Rerbal, Boualem Bouyahiaoui, Abbas Marok, Abdeslam Abtout, Hassina Boukerbout, Kamar Eddine Bensefia Jul 2023

Use Of Aeromagnetic Data For Structural Mapping Of The Tlemcen Mountains (Northwestern Algeria), Lahcen Rerbal, Boualem Bouyahiaoui, Abbas Marok, Abdeslam Abtout, Hassina Boukerbout, Kamar Eddine Bensefia

Turkish Journal of Earth Sciences

In order to refine the geological mapping and to improve our knowledge of the Tlemcen Mountains structure (northwestern Algeria), the interpretation of aeromagnetic data using several processing techniques allowed us to map the Paleozoic basement of Rhar Roubane Mountains and the sedimentary cover constituted by geological formations of Mesozoic and Cenozoic age. Structurally, the Tlemcen Mountains are formed by several structures (e.g., Sebdou Graben), separated by three major transverse faults NNE-SSW (Tafna-Magoura, Oued Chouly and Aïn Tellout transverse faults). We have also been able to highlight a set of deep and shallower structures, trending mainly in NE-SW, N-S, and E-W, …


Spherical Bouguer Effect Of Topography On Gravity With Constant And Laterally Varying Density, Mehmet Si̇mav Jul 2023

Spherical Bouguer Effect Of Topography On Gravity With Constant And Laterally Varying Density, Mehmet Si̇mav

Turkish Journal of Earth Sciences

Gravitational attraction of the Earth's visible topography above the mean sea level is generally regarded as an unwanted signal in various geoscience applications. It should be removed from the observations to reveal the remaining signals of subsurface anomalous density distribution or to satisfy the boundary condition in solving the geodetic boundary value problems. However, the task of determining the gravimetric terrain effects involves tedious numerical computations when high-resolution elevation data is used. While the traditional computational approach relies on flat-Earth approximation and neglects the topographic masses beyond some fixed integration radius, e.g., planar complete Bouguer correction, the modern methods apply …


Textural And Genetic Investigations Of Gold Mineralization In Fault-Controlled Quartzcarbonate Veins In Bayburt-Zarani Area (Eastern Pontides-Ne Turkey), Necati̇ Tüysüz, Gülten Yaylali Abanuz, Oğuzhan Gümrük, Bahri̇can Ar Jul 2023

Textural And Genetic Investigations Of Gold Mineralization In Fault-Controlled Quartzcarbonate Veins In Bayburt-Zarani Area (Eastern Pontides-Ne Turkey), Necati̇ Tüysüz, Gülten Yaylali Abanuz, Oğuzhan Gümrük, Bahri̇can Ar

Turkish Journal of Earth Sciences

The Eastern Pontides Orogenic Belt (EPOB), geographically corresponding to the northeastern part of Turkey hosts several different types of mineralizations that are closely related to Late Mesozoic-Early Cenozoic arc magmatism. Of these, Zarani gold mineralization, which is located in the southern part of the EPOB occurs as quartz-carbonate veins/veinlets within the Pulur metamorphic massif of Paleozoic age. Mineral textures indicate low-temperature vein-type mineralization. Gold mainly occurs in quartz and pyrite. The presence of calcite, dolomite, and sericite in the mineralization indicates near neutral pH conditions of ore-forming fluid. Geochemical analyses of chlorites in the quartz-carbonate veins reveal a temperature of …


Evaluating The Influence Of Recent Tectonic Activity On The River Evolution Using The Identification Of Knickpoints In The South Of Central Alborz Belt, Masoomeh Alaei, Alireza Nadimi, Homayon Safaei, Maryam Dehbozorgi Jul 2023

Evaluating The Influence Of Recent Tectonic Activity On The River Evolution Using The Identification Of Knickpoints In The South Of Central Alborz Belt, Masoomeh Alaei, Alireza Nadimi, Homayon Safaei, Maryam Dehbozorgi

Turkish Journal of Earth Sciences

Change in the steepness of river profiles caused by tectonic forces (uplift and material weakening in fault zones) causes the formation of the tectonically formed knickpoints (TFKs), which is an important geomorphic feature in bedrock river morphology. In this research, knickpoints in a wide area of the south of Central Alborz using the stream gradient (Gd) and the normalized steepness index (k$_{sn}$) were identified. According to the location of the knickpoints in relation to the faults in the area, the TFKs were identified. Analysis of the extracted TFKs with the longitudinal profile, logarithm slope-area plots, and natural logarithm gradient-distance plots …


A Controlled Source Tomography In Sarımeşe, İzmit, At The Western Section Of North Anatolian Fault Zone, Tuğçe Ergün Jul 2023

A Controlled Source Tomography In Sarımeşe, İzmit, At The Western Section Of North Anatolian Fault Zone, Tuğçe Ergün

Turkish Journal of Earth Sciences

A high-resolution two-dimensional tomographic velocity image in the eastern Marmara region along a 1.2 km long N-S trending seismic profile, which crosses the surface rupture of the İzmit earthquake on the North Anatolian Fault (NAF) is presented. A vibroseis source at more than 180 points with 50 receivers was used along the long profile. A regularized inversion technique was applied to the first arrival travel times. More than 6500 first arrivals from 129 shot gathers were analyzed to construct velocity images and were qualitatively evaluated for the fault zone-related effects. The velocity model was constrained to a maximum depth of …


Characteristic Features And Paleoseismological Behaviours Of The Anamas Block Boundary Faults, Southwestern Anatolia, Turkey, Seli̇m Özalp, Hasan Elmaci, Ayhan Yavuzoğlu, Meryem Kara Jul 2023

Characteristic Features And Paleoseismological Behaviours Of The Anamas Block Boundary Faults, Southwestern Anatolia, Turkey, Seli̇m Özalp, Hasan Elmaci, Ayhan Yavuzoğlu, Meryem Kara

Turkish Journal of Earth Sciences

The Anamas Block is located at the apex of the Isparta Angle which is one of the most important tectonic structures of Anatolia. The Isparta Angle, which has a complex tectonic structure, was formed as a result of compressional and extensional tectonic events that initiated from the Late Cretaceous continuing to the present. The GPS and kinematic data indicate the Anamas Block currently rotates clockwise due to the impact of the normal faults (Beyşehir Gölü and Sarıidris) with a minor right lateral strike-slip component on the east and west boundaries, while it is moved to the southeast by the effect …


The Role Of Stress Barriers On The Shape Of Future Earthquakes In The Mentawai Section Of The Sunda Megathrust, Süleyman Sami̇ Nalbant, Mairead Nic Bhloscaidh, John Mccloskey, Cengi̇z İpek, Murat Utkucu Jan 2023

The Role Of Stress Barriers On The Shape Of Future Earthquakes In The Mentawai Section Of The Sunda Megathrust, Süleyman Sami̇ Nalbant, Mairead Nic Bhloscaidh, John Mccloskey, Cengi̇z İpek, Murat Utkucu

Turkish Journal of Earth Sciences

The underlying causes of apparent barriers to rupture propagation on earthquake faults that appear strongly to constrain rupture shape and slip distributions, are the ongoing subject of research. Preseismic stress shadows on the rupturing segment, resulting from the history of slip preceding a great earthquake, are proposed here as one possible cause of such barriers. We focus on the Mentawai section of the Sunda megathrust since it is unique in having its long seismic history recorded in shallow water corals, as well as detailed slip distributions for events in the last ?seismic cycle?, and modern geodetic information on the distribution …


Land Subsidence Due To Natural Gas Extraction In The Thrace Basin (Nw Turkey) And Its Influence On The North Anatolian Fault Under The Marmara Sea, Tohid Nozadkhalil, Zi̇yadi̇n Çakir, Semi̇h Ergi̇ntav, Uğur Doğan, Thomas R. Walter Jan 2023

Land Subsidence Due To Natural Gas Extraction In The Thrace Basin (Nw Turkey) And Its Influence On The North Anatolian Fault Under The Marmara Sea, Tohid Nozadkhalil, Zi̇yadi̇n Çakir, Semi̇h Ergi̇ntav, Uğur Doğan, Thomas R. Walter

Turkish Journal of Earth Sciences

We map surface deformation in the Thrace region of Turkey using the Sentinel-1 Synthetic Aperture Radar (SAR) data. Interferometric Synthetic Aperture Radar (InSAR) time series analysis of the SAR data acquired between 2014 and 2020 on ascending and descending orbits reveals large-scale subsidence (~110 × 60 km) with rates reaching up to 10 ± 1.5 mm/yr. We relate this deformation to natural gas reservoir operations, such as gas exploitation and extraction activities that have been taking place in the region for decades, an inference being supported by the strong correlation between the InSAR time series and the variation in natural …