Article
Geosciences, Multidisciplinary
Herve Rezeau, Marc Hassig, Emin Sadikhov, Massimo Chiaradia, Robert Moritz
Summary: The present-day configuration of the Lesser Caucasus and Eastern Pontides regions has been shaped by multiple episodes of arc magmatism and tectonic events. These regions are also rich in mineral deposits, such as polymetallic deposits and porphyry Cu-Mo deposits. New zircon Hf isotopic data has provided insights into the geological evolution of these areas, highlighting three distinct cycles of arc magmatism and revealing the presence of a composite basement. This study offers new constraints for understanding the geodynamic evolution of the region and provides valuable information for mineral exploration.
EARTH-SCIENCE REVIEWS
(2023)
Review
Geosciences, Multidisciplinary
Yener Eyuboglu, Francis O. Dudas, Di-Cheng Zhu, M. Santosh, Ze Liu, Nilanjan Chatterjee, Keewook Yi
Summary: The research on the Eastern Pontides Orogenic Belt in northeastern Turkey reveals a complex continental arc system with multi-stage Late Cretaceous magmatism showing different characteristics in terms of rock types and geochemical features, indicating a significant geological differentiation.
Article
Geology
S. Tassara, J. J. Ague, V. Valencia
Summary: This study reports the discovery of Acadian hydrous ultramafic cumulate rocks in southern New England, USA, formed through deep-seated fractional crystallization processes, representing one of the few preserved deep subarc hydrous cumulates worldwide. The findings propose a genetic link between these rocks and the evolved coeval plutonism in central-southern New England, supporting the hypothesis that differentiation of mantle-derived hydrous magmas by fractional crystallization and assimilation processes in the deep crust is fundamental in the production of intermediate to silicic magmatism and the geochemical evolution of the continental crust.
Article
Geology
Ezgi Saglam, Turgut Duzman, Cemre Ay, Aral I. Okay, Gultekin Topuz, Gursel Sunal, Ercan Ozcan, Demir Altiner, Aynur Hakyemez, Jia-Min Wang, Andrew R. C. Kylander-Clark
Summary: During the Late Cretaceous, a 2700 km-long magmatic arc extended from the Lesser Caucasus through the northern margin of the Pontides into ABTS in the Balkans. The arc magmatism started in the Turonian, peaked in the middle Campanian, and became rare after the late Campanian. The magmatism showed calc-alkaline to high-K calc-alkaline composition and subduction geochemical signatures.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geochemistry & Geophysics
Ze Liu, Di-Cheng Zhu, Oliver Jagoutz, Herve Rezeau, Qing Wang, Yener Eyuboglu
Summary: The study of two intrusive series in the Yusufeli region of the Eastern Pontides arc in NE Turkey reveals differences in their magma genesis, geological ages, and magma formation processes. The magmas of both intrusive complexes are derived from multiple mantle magma pulses and crystallized at upper crustal levels. Combining with previous research, the geochemical compositions and spatial relationships of the two intrusive complexes provide insights into the southward subduction of the Paleotethys oceanic lithosphere in the Early to Late Jurassic.
JOURNAL OF PETROLOGY
(2021)
Article
Geochemistry & Geophysics
Jean-Baptiste Jacob, Emilie Janots, Stephane Guillot, Daniela Rubatto, Kevin Freville, Jeremie Melleton, Michel Faure
Summary: The Oisans-Pelvoux massif in the Western Alps records high temperature metamorphism and intense migmatization during the Variscan orogeny. New findings of high pressure mafic granulites provide insights into the early evolution of the unit, with relics of Mn-rich garnet cores revealing prograde stages and HP assemblages indicating peak-P conditions and subsequent decompression to HT granulite-facies conditions.
Article
Geochemistry & Geophysics
Masoumeh Zare-Shooli, Zahra Tahmasbi, Songjian Ao, Hua-Feng Zhang, Adel Saki, Ahmad Ahmadi-Khalaji, Chris Yakymchuk, Rasoul Esmaeili, Orhan Karsli
Summary: Migmatites in the Boroujerd region of Western Iran are associated with felsic and mafic magmatism, with the relationship between partial melting and magmatism being unclear. U-Pb zircon geochronology was used to determine the timing of anatexis in four metapelite migmatite samples. The detrital zircons in the migmatites correspond to the Paleozoic and Mesozoic magmatism in the region, while zircon rims and neoblastic grains suggest contact metamorphism and partial melting due to Middle Jurassic magmatism.
Article
Multidisciplinary Sciences
Yang Yang, Bin Xiong, Sanxi Peng, Siqin Liu, Hanbo Chen, Tianyu Zhang
Summary: This paper summarizes the mechanism and impact of magmatic rock intrusion into coal seams, introduces the characteristics and detection method of transient electromagnetic method (TEM), and analyzes its effectiveness in detecting the ranges of intruded coal seams.
Review
Geology
Y. Yilmaz, E. Yigitbas
Summary: The Eastern Pontides are the northeasternmost component of the Anatolian orogen and are closely associated with the evolution of the Ankara-Erzincan Suture. It records the geological events from the opening to the elimination of the surrounding oceans. The Pontides experienced four collisional events throughout its development, including forearc-arc collision and continent-arc collision.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geochemistry & Geophysics
Rongsong Tian, Xi Wang, Rongfeng Ge, Wenbin Zhu, Guoai Xie
Summary: This study investigates the early to middle Paleozoic tectonic evolution of the Alxa block using geochronological and geochemical analyses of igneous and metamorphic rocks. The results show that the northern margin of the Alxa block exhibits similar characteristics to the Bainaimiao arc, indicating a western extension of the arc. In contrast, the Alxa block experienced continental arc magmatism triggered by southward subduction of the Paleo-Asian Ocean. Regional metamorphic events further support arc-continent collision in the northern Alxa block. These findings suggest that the Alxa block was likely part of the North China Craton during the early Paleozoic.
Article
Mathematics
G. Metafune, L. Negro, C. Spina
Summary: This article studies elliptic and parabolic problems governed by the singular elliptic operators in the half-space.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2022)
Article
Geology
Emre Aydincakir, Cem Yucel, Abdullah Kaygusuz, Ozgur Bilici, Keewook Yi, Youn-Joong Jeong, Z. Samet Guloglu
Summary: The plutonic rocks in the Eastern Pontides in NE Turkey have been studied using new geochemical, isotopic and geochronological data. Two different plutons were identified, one formed by partial melting of a depleted mantle and the other formed by partial melting of an enriched mantle metasomatized by slab-derived sediments. These rocks provide insights into the tectonic events during the Middle Jurassic, related to the closure of the Paleotethys oceanic slab.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geochemistry & Geophysics
Anwesa Banerjee, N. Prabhakar, Nicole Sequeira, Nathan Cogn, Abhijit Bhattacharya
Summary: The study reveals the convergence of Aravalli Delhi Fold Belt and Central Indian Tectonic Zone in the GC sector of west-central India. Through analysis of deformation structures, metamorphic phase equilibria, and geochronological-geochemical data, the dynamics of the Early Neoproterozoic CITZ-ADFB accretion are addressed. The findings provide insights into the crustal convergence and rock evolution processes.
Article
Geosciences, Multidisciplinary
T. S. Petry, R. P. Philipp, D. I. G. Cabrita, D. L. Jamal, R. Machado, C. Lana
Summary: The rocks from the Chidzolomondo Complex in the Southern Irumide Belt in NW Mozambique provide new insights into the subduction and accretionary phases of the belt's evolution. These rocks exhibit different chemical compositions and ages, which also provide evidence for the metamorphic processes and formation.
PRECAMBRIAN RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Abdullah Sar, Sevcan Kurum, Ahmet Feyzi Bingol
Summary: This study investigates the magmatic evolution of the Eastern Pontides orogenic belt in northeastern Turkey using new zircon U-Pb ages, Lu-Hf isotopes, and whole-rock geochemical and Sr-Nd isotopic analyses. The results suggest a heterogeneous magma source, possibly derived from a juvenile lower crust. Additionally, the magmatism in the area is associated with the collision of the Anatolide Taurid Platform with the Pontides.
JOURNAL OF EARTH SCIENCE
(2023)
Article
Geology
Remziye Akdogan, Istvan Dunkl, Aral I. Okay, Xiumian Hu, Gultekin Topuz
Summary: Apatite fission-track and (U-Th)/He ages from Carboniferous to Eocene siliciclastic rocks in the Istanbul Zone of NW Turkey suggest three major deformation and uplift/exhumation phases. These phases are attributed to orogeny, accretion of oceanic plateaus, and closure of oceanic domains in the region.
INTERNATIONAL GEOLOGY REVIEW
(2022)
Article
Geosciences, Multidisciplinary
A. M. Celal Sengor, Nalan Lom, Cengiz Zabci, Gursel Sunal, Tayfun Oner
Summary: The Saharides, a major Neoproterozoic orogenic system in North Africa, formed between 900 to 500 Ma ago, involving subduction-accretion complexes and the formation of new continental crust. The evolution of the Saharides was driven by subduction and strike-slip stacking of arc material, without continental collisions. The entire Sahara region is underlain by a double orocline structure, similar to the Hercynian double orocline in western Europe and northwestern Africa.
INTERNATIONAL JOURNAL OF EARTH SCIENCES
(2022)
Review
Geosciences, Multidisciplinary
A. M. Celal Sengor, Gursel Sunal, Boris A. Natal'in, Rob van der Voo
Summary: The Altaids is the largest orogenic belt in Central Asia formed by Turkic-type orogeny, with a duration of 600 million years and a continental crust growth rate similar to the Phanerozoic. The methods used to reconstruct the history of the Altaids can also be applied to late Precambrian orogens, but cannot establish a biostratigraphy. Detailed knowledge of the strain histories in soldering orogenic belts is crucial for accurate reconstruction.
EARTH-SCIENCE REVIEWS
(2022)
Article
Geology
Gursel Sunal, Ali Akin, M. Korhan Erturac, Cemre Ay, Istvan Dunkl
Summary: The Almacik Block is a tectonic sliver formed during the activity of the North Anatolian Fault Zone. The study analyzes magmatic rocks using the zircon U-Pb method and examines the palaeo-exhumation evolutions of different tectonic zones using the zircon (U-Th)/He technique.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geosciences, Multidisciplinary
Semih Can Ulgen, A. M. Celal Sengor, Mehmet Keskin, Namik Aysal, Tayfun Oner
Summary: Late Cretaceous dykes and volcano-sedimentary units were discovered in Istanbul, Turkey, along with the Cavusbasi pluton. These findings suggest the presence of a magma plumbing system and a controlling structure for the dyke system.
INTERNATIONAL JOURNAL OF EARTH SCIENCES
(2022)
Article
Geosciences, Multidisciplinary
Aral I. Okay, Andrew R. C. Kylander-Clark
Summary: Detrital zircon ages from Upper Cretaceous sandstones in the Pontides and Anatolide-Tauride Block reveal differences in zircon compositions between the two regions. The absence of sediment transport between the two blocks during the latest Cretaceous suggests an earlier deformation event in the Bornova Flysch Zone related to ophiolite obduction. The predominance of Carboniferous detrital zircons highlights the significance of Carboniferous magmatic activity in the Anatolide-Tauride Block.
INTERNATIONAL JOURNAL OF EARTH SCIENCES
(2023)
Article
Geology
Donna L. Whitney, Jonathan R. Delph, Stuart N. Thomson, Susan L. Beck, Gilles Y. Brocard, Michael A. Cosca, Michael H. Darin, Nuretdin Kaymakci, Maud J. M. Meijers, Aral I. Okay, Bora Rojay, Christian Teyssier, Paul J. Umhoefer
Summary: Escape tectonics is a mechanism for the formation of new plates, in which lithospheric fragments move laterally along strike-slip faults in response to collision. Analysis of thermochronology data and seismic images near the East Anatolian fault zone provides insights into the development of the Anatolian plate and escape system. The younger ages of rocks in and near the EAFZ, as well as the presence of strong Arabian lithospheric mantle beneath the Anatolian crust, suggest that thermal activity and underthrusting of Arabian lithosphere played a fundamental role in the formation of the Anatolian plate and escape system.
Article
Geology
Cumhur Babaoglu, Gultekin Topuz, Aral I. Okay, Serhat Koksal, Jia-Min Wang, Fatma Toksoy-Koksal
Summary: This paper investigates the petrology and age of the volcanism in the Istanbul Zone, NW Turkey. It discovers minor alkaline basalt and acidic volcanic rocks that date back to approximately 261 million years ago. It suggests that the volcanism occurred in an extensional setting concurrent with the northward subduction of the Palaeo-Tethys beneath the Sakarya and Istanbul zones after the Variscan orogeny.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geology
Ezgi Saglam, Turgut Duzman, Cemre Ay, Aral I. Okay, Gultekin Topuz, Gursel Sunal, Ercan Ozcan, Demir Altiner, Aynur Hakyemez, Jia-Min Wang, Andrew R. C. Kylander-Clark
Summary: During the Late Cretaceous, a 2700 km-long magmatic arc extended from the Lesser Caucasus through the northern margin of the Pontides into ABTS in the Balkans. The arc magmatism started in the Turonian, peaked in the middle Campanian, and became rare after the late Campanian. The magmatism showed calc-alkaline to high-K calc-alkaline composition and subduction geochemical signatures.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geosciences, Multidisciplinary
A. M. Celal Sengor, Demir Altiner, Cengiz Zabci, Guersel Sunal, Nalan Lom, Esref Aylan, Tayfun Oner
Summary: The Cimmerian Continent is a narrow continental strip that rifted from the Gondwana-Land margin during the Permian and collided with the Laurasian margin sometime between the latest Triassic and the late Jurassic. It did not leave Gondwana-Land in one piece, but separated into several parts, with the northern part forming a large island arc type ribbon continent. The northern margin of the Cimmerian Continent is of Pacific-type and not Atlantic-type. The continent had a serpentine motion as it traversed the Tethyan realm and had a complex internal tectonics.
EARTH-SCIENCE REVIEWS
(2023)
Article
Geochemistry & Geophysics
Aral I. Okay, Ercan Ozcan, Muzaffer Siyako, Kerem A. Burkan, Andrew R. C. Kylander-Clark, Michael D. Bidgood, David Shaw, Michael D. Simmons
Summary: The Thrace Basin, with its complex tectonic history, is a challenging case for classification. New geochronological and biostratigraphic data provide insights into its tectonic evolution, revealing that the basin primarily contains early Oligocene siliciclastic turbidites sourced from the Rhodope Complex. The exhumation of the northern Rhodope Complex coincided with the main subsidence in the Thrace Basin, suggesting a connection between crustal rotation and basin development.
Article
Geosciences, Multidisciplinary
Ali Osman Yucel, Ercan Ozcan, Rita Catanzariti, Aynur Hakyemez, Aral I. Okay, Attila Ciner, Ali Akin
Summary: New field observations and discovery of calcareous nannofossils and planktonic foraminifera in the shallow-marine Cayraz Formation in Haymana Basin, Central Anatolia, allows for the revision of its stratigraphy and the establishment of a biostratigraphic scheme. Calcareous nannofossils in the upper part of the underlying Eskipolatli Formation suggest the initiation of the Cayraz shelf system in the middle Ypresian, while marly parts of the Cayraz Formation indicate Zone CNE6 in the late Ypresian. Hemipelagic marls in the upper part of the formation yield calcareous nannofossils indicating Zone CNE9 and CNE10 in the lower samples, and Zone CNE12 in the upper samples. The same beds also yield planktonic foraminifers indicating Zone E8 and E9. The end of shallow-marine sedimentation in the Cayraz section is proposed to be in the middle Lutetian.
TURKISH JOURNAL OF EARTH SCIENCES
(2023)
Article
Geology
Donna L. Whitney, Jonathan R. Delph, Stuart N. Thomson, Susan L. Beck, Gilles Y. Brocard, Michael A. Cosca, Michael H. Darin, Nuretdin Kaymakci, Maud J. M. Meijers, Aral I. Okay, Bora Rojay, Christian Teyssier, Paul J. Umhoefer
Summary: This study provides insights into the development of the new plate and escape system by using thermochronology data and seismic images. It is found that the rocks near the East Anatolian fault zone are significantly younger, indicating thermal activity triggered by strike-slip faulting. The images also reveal that the underthrusting of the strong Arabian lithosphere played a crucial role in the localization of the fault zone and the formation of the Anatolian plate and escape system.
Article
Paleontology
Ercan Ozcan, Ali Osman Yucel, Simon F. Mitchell, Johannes Pignatti, Michael D. Simmons, Aral Okay, Levent Sina Erkizan, Munire Nur Gultekin
Summary: This article introduces a unique combination of carbonate-clastic and larger benthic foraminifera in the middle to upper Eocene of northwest Turkey, and describes a newly discovered genus of larger benthic foraminifera, Caudriella. The study reveals the distribution of Caudriella in both the Caribbean and Western Neo-Tethys regions. Comparative analysis of the embryonic-nepionic stages of Caudriella and the emendation of its diagnosis are also conducted.
JOURNAL OF FORAMINIFERAL RESEARCH
(2022)