Browsing by Author "Kaymakci, Nuretdin"

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Age and Kinematics of the Burdur Basin: Inferences for the Existence of the Fethiye Burdur Fault Zone in Sw Anatolia (Turkey)
(Elsevier, 2018) Ozkaptan, Murat; Kaymakci, Nuretdin; Langereis, Cor G.; Gulyuz, Erhan; Ozacar, A. Arda; Uzel, Bora; Sozbilir, Hasan
The Burdur Basin is a late Miocene to Pliocene fluvio-lacustrine basin in SW Anatolia. It is developed within the postulated Fethiye-Burdur Fault Zone, which was argued to be a sinistral strike-slip fault zone developed in response to propagation of the Pliny-Strabo STEP fault into SW Anatolia (Turkey). In order to assess the presence and tectonic characteristics of the fault zone, we conducted a paleomagnetic study in the Burdur basin that involved rock magnetic experiments, Anisotropy of Magnetic Susceptibility (AMS) measurements and developing a magnetostratigraphy for dating purposes. The obtained age model constrains most part of the tectonic evolution of the basin. The well exposed (similar to 270 m thick) Burdur section revealed 3 normal and 2 reverse polarity magnetozones. We propose that the Burdur Formation spans most of the Gauss Chron (similar to 3.4-2.5 Ma) which implies a sedimentation rate of > 18 cm/kyr. The AMS results in the section indicate NW-SE directed extension. In addition, we have also conducted kinematic analyses from 1790 fault slip data collected at 44 sites distributed within the supposed Fethiye Burdur Fault Zone in the region. The results indicate that the region has been developed under a NW-SE directed extensional deformation regime and was dominated by NE-SW striking normal faults from late Miocene to recent. Few NW-SE striking normal faults with strike-slip components are categorized as transfer faults, which accommodated differential stretching between the Burdur and Cameli basins. Stretching amounts increase southwards demonstrating a dextral transtensional character of the transfer faults. We have not observed any significant strike-slip motion along the NE-SW striking faults, which challenges the presence and sinistral transcurrent nature of the supposed Fethiye Burdur Fault Zone.
Deformation in Sw Anatolia (Turkey) Documented by Anisotropy of Magnetic Susceptibility Data
(Amer Geophysical Union, 2021) Ozkaptan, Murat; Gulyuz, Erhan; Uzel, Bora; Langereis, Cor G.; Ozacar, A. Arda; Kaymakci, Nuretdin
Convergence between the Eurasian and the African plates in the West Anatolian-Aegean region results in a trench retreat due to slab roll-back and tearing of the subducted African lithosphere. The upper plate response of this process gave way to back-arc extension in the region. We have conducted a very detailed anisotropy of magnetic susceptibility (AMS) study on the Neogene rocks in SW Anatolia to unravel the style and magnitudes of deformation. For this purpose, from 83 sites in 11 structurally homogeneous domains, 1,680 paleomagnetic samples were analyzed. The results show that AMS fabrics are related to the tectonic deformation and that the magnetic lineation (maximum susceptibility axis, k(1)) is parallel to inferred maximum extension, while minimum susceptibility (k(3)) is typically normal to the bedding plane, corresponding to a preserved compaction associated with deposition fabric. The intermediate axis (k(2)) is parallel to a second extension direction and indicates that the region has been under the control of multi-directional extension during the Neogene. Two main magnetic lineation directions are identified and represent Oligocene to middle Miocene E-W, and late Miocene to Pliocene NW-SE oriented extension. The magnetic lineation directions are dominantly parallel or perpendicular to the general strikes of the normal faults. The results show that the deformation in the region resembles two differentially stretched rubber sheets under the influence of SW oriented extension, exerted by the southward retreating Eastern Mediterranean subduction system.
Kinematic and Thermal Evolution of the Haymana Basin, a Fore-Arc To Foreland Basin in Central Anatolia (Turkey)
(Elsevier, 2019) Gulyuz, Erhan; Ozkaptan, Murat; Kaymakci, Nuretdin; Persano, Cristina; Stuart, Finlay M.
Gondwana (Tauride/kirsehir blocks) and Eurasia (Pontides) derived continental blocks delimit the Haymana basin, central Turkey, to the south and the north, respectively. The boundaries of these blocks define the IzmirAnkara-Erzincan and Intra-Tauride Suture zones which are straddled by a number of Late Cretaceous to Oligocene marine to continental basins. The Haymana Basin is located at the junction of the IAESZ and ITSZ and comprises Upper Cretaceous to Middle Eocene basin infill deposited in response to the interaction of these blocks. The basin provides a unique opportunity to unravel spatio-temporal relationships related to the timing of late stage subduction history of Neo-Tethys Ocean and subsequent collision of the intervening continental blocks. We have conducted a multidisciplinary study in the region that includes mapping of major structures combined with fault kinematic analyses. E-W striking folds dominate the basin, cross-section balancing of these structures indicates around 25% roughly N-S shortening in the region. Paleostress studies indicate that the basin was initially subjected to N-S to NNE-SSW extension until the middle Paleocene (phase 1) and then N-S directed syn-depositional compression and coeval E-W directed extension until the middle Miocene (phase 2) implying strike-slip deformation and pure shear shortening in the basin. These different deformation phases are attributed to first fore-arc (subduction) basin development then foreland (collision) stages of the basin. Apatite (U-Th)/He dating of 5 samples indicate that exhumation of the SE segment of the basin started in early Oligocene, whereas the NW segment of the basin exhumed in the early Miocene. The differential uplift is possibly related to progressive north-westwards movement of Derekby basin bounding fault at the north. We propose that the Haymana basin evolved from extensional forearc basin during the late Cretaceous to early Paleocene and foreland basin after the terminal subduction and subsequent collision of Tauride and Pontide blocks.
Late Neogene Oroclinal Bending in the Central Taurides: a Record of Terminal Eastward Subduction in Southern Turkey
(Elsevier Science Bv, 2016) Koc, Ayten; van Hinsbergen, Douwe J. J.; Kaymakci, Nuretdin; Langereis, Cornelis G.
The Tauride fold-thrusts belt formed during similar to S-N convergence between Africa and Eurasia since Cretaceous time. The western end of the central Taurides strike NW-SE, highly obliquely to the overall convergence direction, and connect to the NE-SW Beydaglan-Lycian Nappe flank of the western Taurides, forming the so-called 'Isparta Angle'. In Neogene time, the western and central Taurides and the inner part of the Isparta Angle became overlain by Neogene sedimentary basins including Manavgat, Koprucay and Aksu, characterized by marine clastics and carbonates. The eastern limb of the Isparta Angle experienced multidirectional Miocene to Present extension, whereas E-W shortening affected the marine sedimentary basins in the heart of the Isparta Angle. To quantitatively reconstruct the Neogene kinematic evolution of the Taurides, towards restoring the subduction system accommodating Africa-Eurasia convergence, we paleomagnetically assess if and when vertical axis rotations affected the Manavgat, Koprucay, and Aksu basins in Early Miocene to Pliocene times. We show that the northern Koprucay Basin rotated similar to 20-30 degrees clockwise, the Manavgat Basin underwent similar to 25-35 degrees counterclockwise rotation, and the Aksu Basin underwent no rotation since the Early-Middle Miocene. It was previously shown that the Beydaglari region underwent a post-Middle Miocene similar to 20 degrees counterclockwise rotation. These results show that the prominent oroclinal salient geometry of the western Taurides thus acquired, at least in part, since Miocene times, that the Koprucay Basin rotated relative to the Aksu Basin along the Aksu thrust, and that the Beydaglari platform rotated relative to the Aksu Basin along the Bucak thrust, which must have both been active until Late Neogene time. This synchronous E-W shortening in the heart of the Isparta Angle, and multidirectional extension in its eastern limb may be explained by relative westward retreat of an eastward dipping subducting Antalya slab that has previously been imaged by seismic tomography and a Benioff zone. The Neogene Bucak thrust west of the Aksu Basin may represent the most recent surface expression of the Antalya subduction zone. (C) 2015 Elsevier B.V. All rights reserved.
Magnetostratigraphy and Paleoecology of the Hominid-Bearing Locality, Corakyerler, Tuglu Formation (Cankiri Basin, Central Anatolia)
(Taylor & Francis inc, 2016) Kaya, Ferhat; Kaymakci, Nuretdin; Bibi, Faysal; Eronen, Jussi T.; Pehlevan, Cesur; Erkman, Ahmet C.; Fortelius, Mikael
Ouranopithecus turkae, from the late Miocene of Corakyerler in Central Anatolia, is considered one of the last known occurrences of great ape in the eastern Mediterranean. The Corakyerler fauna has previously been correlated with MN 11 to early MN 12 on the basis of biochronology, and its faunal composition has been found to contrast with those from contemporaneous sites. In this paper, we present the magnetostratigraphy of the Corakyerler site and an expanded interpretation of its paleobiogeographical and paleoecological contexts. The paleomagnetic results reveal two intervals of normal polarity and an intervening interval of reversed polarity in the main fossiliferous section. Of the three likely age correlations spanning 8.13-7.15Ma (MN 11-MN 12), we favor correlation with chron 4n, with a possible age range of the fossiliferous deposit between 8.11 and 7.64Ma (late MN 11). The geographic distribution of genus-level faunal similarity and mean hypsodonty show that Corakyerler is a typical representative of the Pikermian chronofauna with a wide range of faunal similarity, including late Miocene localities from the eastern Mediterranean, eastern Asia, and eastern Africa. Lithological and sedimentological characteristics of the fossiliferous horizon, however, indicate a lacustrine depositional environment and relatively humid local conditions within the more arid regional context. This special setting could explain the unexpected occurrence of a hominid primate at Corakyerler.Citation for this article: Kaya, F., N. Kaymakci, F. Bibi, J. T. Eronen, C. Pehlevan, A. C. Erkman, C. G. Langereis, and M. Fortelius. 2016. Magnetostratigraphy and paleoecology of the hominid-bearing locality Corakyerler, Tulu Formation (Cankr Basin, Central Anatolia). Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2015.1071710.
A Miocene Onset of the Modern Extensional Regime in the Isparta Angle: Constraints From the Yalva‡ Basin (Southwest Turkey)
(Springer, 2016) Koc, Ayten; Kaymakci, Nuretdin; van Hinsbergen, Douwe J. J.; Vissers, Reinoud L. M.
The pre-Neogene Tauride fold-and-thrust belt, comprising Cretaceous ophiolites and metamorphic rocks and non-metamorphic carbonate thrust slices in southern Turkey, is flanked and overlain by Neogene sedimentary basins. These include poorly studied intra-montane basins including the Yalva double dagger Basin. In this paper, we study the stratigraphy, sedimentology and structure of the Yalva double dagger Basin, which has a Middle Miocene and younger stratigraphy. Our results show that the basin formed as a result of multi-directional extension, with NE-SW to E-W extension dominating over subordinate NW-SE to N-S extension. We show that faults bounding the modern basin also governed basin formation, with proximal facies close to the basin margins grading upwards and basinwards into lacustrine deposits representing the local depocentre. The Yalvac Basin was a local basin, but a similar, contemporaneous history recently reconstructed from the AltA +/- napa Basin, similar to 100 km to the south, shows that multi-directional extension dominated by E-W extension was a regional phenomenon. Extension is still active today, and we conclude that this tectonic regime in the study area has prevailed since Middle Miocene times. Previously documented E-W shortening in the Isparta Angle along the Aksu Thrust, similar to 100 km to the southwest of our study area, is synchronous with the extensional history documented here, and E-W extension to its east shows that Anatolian westwards push is likely not the cause. Synchronous E-W shortening in the heart and E-W extension in the east of the Isparta Angle may be explained by an eastwards-dipping subduction zone previously documented with seismic tomography and earthquake hypocentres. We suggest that this slab surfaces along the Aksu thrust and creates E-W overriding plate extension in the east of the Isparta Angle. Neogene and modern Anatolian geodynamics may thus have been driven by an Aegean, Antalya and Cyprus slab segment that each had their own specific evolution.
Miocene Tectonic History of the Central Tauride Intramontane Basins, and the Paleogeographic Evolution of the Central Anatolian Plateau
(Elsevier, 2017) Koc, Ayten; Kaymakci, Nuretdin; Van Hinsbergen, Douwe J. J.; Kuiper, Klaudia F.
Marine Lower-Upper Miocene deposits uplifted to > 2 km elevation in the Tauride mountains of southern Turkey are taken as evidence for the rise of a nascent plateau. The dynamic causes of this uplift are debated, but generally thought to be a regional dynamic topographic effect of slab motions or slab break-off. Immediately adjacent to the high Tauride mountains lie the Central Tauride Intramontane Basins, which consist of Miocene and younger fluvio-lacustrine basins, at much lower elevations than the highly uplifted marine Miocene rocks. These basins include the previously analyzed Altinapa and Yalvac basins, as well as the until now undescribed rigin Basin. In this paper, we aim to constrain the paleogeography of the Central Tauride Intramontane Basins and determine the role of the tectonics driving the formation of the high Miocene topography in southern Turkey. Therefore, we provide new data on the stratigraphy, sedimentology and structure of the continental Ilgin Basin. We provide an 40Ar/39Ar age of 11.61 +/- 0.05 Ma for pumice deposits in the stratigraphy. We provide paleostress inversion analysis based on growth faults showing that the basin formed during multi-directional extension, with NE-SW to E-W dominating over subordinate N-S extension. We conclude that major, still-active normal faults like the Aksehir Fault also controlled Miocene Ilgin basin formation, with proximal facies close to the basin margins grading upwards and basinwards into lacustrine deposits representing the local depocenter. The Ilgin Basin was a local depocenter, but it may have connected with the adjacent Altinapa Basin during high lake levels in late Serravallian time. The Ilgin Basin and the other continental basins provide key constraints on the paleogeography and tectonic history of the region. These continental basins were likely close to the paleocoastline during the Late Miocene after which there must have been major differential uplift of the Taurides. We suggest that the extension we documented in the Central Tauride intramontane basins are in part responsible for the major topography that characterizes the Central Taurides today. The causes of extension remain engmatic, but we suggest that the tomographically imaged Antalya Slab may have caused the contemporaneous formation of NE-SW trending syn-contractional basins in the west and NW-SE trending Central Tauride intramontane basins in the east by slab retreat. Our study highlights that the Neogene deformation history, and perhabs even active tectonics, may be strongly affected by complex slab geometry in SW Turkey, and that crustal deformation plays an important role in generating the Miocene Tauride topography. The role of this crustal deformation needs to be taken into account in attempts to explain the ride of the Taurides and the evolution of the Anatolian Plateau. Marine Lower-Upper Miocene deposits uplifted to > 2 km elevation in the Tauride mountains of southern Turkey are taken as evidence for the rise of a nascent plateau. The dynamic causes of this uplift are debated, but generally thought to be a regional dynamic topographic effect of slab motions or slab break-off. Immediately adjacent to the high Tauride mountains lie the Central Tauride Intramontane Basins, which consist of Miocene and younger fluvio-lacustrine basins, at much lower elevations than the highly uplifted marine Miocene rocks. These basins include the previously analyzed Altinapa and Yalvac basins, as well as the until now undescribed rigin Basin. In this paper, we aim to constrain the paleogeography of the Central Tauride Intramontane Basins and determine the role of the tectonics driving the formation of the high Miocene topography in southern Turkey. Therefore, we provide new data on the stratigraphy, sedimentology and structure of the continental Ilgin Basin. We provide an 40Ar/39Ar age of 11.61 +/- 0.05 Ma for pumice deposits in the stratigraphy. We provide paleostress inversion analysis based on growth faults showing that the basin formed during multi-directional extension, with NE-SW to E-W dominating over subordinate N-S extension. We conclude that major, still-active normal faults like the Aksehir Fault also controlled Miocene Ilgin basin formation, with proximal facies close to the basin margins grading upwards and basinwards into lacustrine deposits representing the local depocenter. The Ilgin Basin was a local depocenter, but it may have connected with the adjacent Altinapa Basin during high lake levels in late Serravallian time. The Ilgin Basin and the other continental basins provide key constraints on the paleogeography and tectonic history of the region. These continental basins were likely close to the paleocoastline during the Late Miocene after which there must have been major differential uplift of the Taurides. We suggest that the extension we documented in the Central Tauride intramontane basins are in part responsible for the major topography that characterizes the Central Taurides today. The causes of extension remain engmatic, but we suggest that the tomographically imaged Antalya Slab may have caused the contemporaneous formation of NE-SW trending syn-contractional basins in the west and NW-SE trending Central Tauride intramontane basins in the east by slab retreat. Our study highlights that the Neogene deformation history, and perhabs even active tectonics, may be strongly affected by complex slab geometry in SW Turkey, and that crustal deformation plays an important role in generating the Miocene Tauride topography. The role of this crustal deformation needs to be taken into account in attempts to explain the ride of the Taurides and the evolution of the Anatolian Plateau.
Neogene Kinematics of the Potwar Plateau and the Salt Range, Nw Himalayan Front: a Paleostress Inversion and Ams Study
(Taylor & Francis inc, 2022) Qayyum, Abdul; Poesse, Jorik Willem; Kaymakci, Nuretdin; Langereis, Cornelis G.; Gulyuz, Erhan; Ahsan, Naveed
We provide new kinematic data from the Potwar Plateau (Pakistan) to evaluate the tectonic evolution of the region during the Neogene. The plateau is bound by two major strike-slip faults in the west and the east, accommodating its southwards translation. We have recognized two Neogene deformation phases in the plateau, based on paleostress inversion and Anisotropy of Magnetic Susceptibility (AMS) tensors. The first phase lasted until the early Pliocene and was characterized by vertical minor stress and N-S compression, implying thrust tectonics. The second deformation phase is characterized by a near-vertical intermediate principal stress and near-horizontal major and minor stresses, interpreted to be associated with strike-slip tectonics since the late Pliocene. K-int vectors from 21 sites are relatively compatible with the major principal stress orientations (sigma(1)) and indicate two distinct domains. This is possibly because K-min orientations are related to compaction, whereas K-int orientations were always parallel to tectonic shortening and hence compression direction during both strike-slip (post-late Pliocene) and thrusting (pre-late Pliocene) phases. These phases are characterized by swapping of (sigma(2)) and (sigma(3)) orientations while (sigma(1)) maintained its orientation. The most prominent change occurs at the western part of the Potwar Plateau, where major principal stress directions (sigma(1)) and K-int axes fan out south-westwards. The eastern domain is dominated by NE-SW trending folds and thrust faults, which are absent in the western domain. These structural features are interpreted to be the result of the distribution of deposits of the Neoproterozoic Salt Range Formation as a substratum below the Potwar Plateau. The Salt Range Formation is very thick and widespread in the west area and almost absent in the east. This factor led to unconstrained southwards gliding of the Potwar Plateau over the salt deposits in the west as opposed to frictional sliding and substantial internal deformation in the east.
Paleobathymetric Evolution of the Miocene Deposits of the Gombe Sector of the Lycian Foreland and Aksu Basins in Antalya, Turkey
(Tubitak Scientific & Technological Research Council Turkey, 2020) Sis, Fatih Seckin; Kouwenhoven, Tanja; Koc, Ayten; Kaymakci, Nuretdin
The evolution of the Lycian Foreland and Aksu basins are associated with the Africa-Eurasia convergence and collision of intervening continental blocks. Both basins developed around the Beydaglari, a Mesozoic carbonate platform, which constitutes the main component and western limb of the Isparta Angle. The Gombe Basin is an integral part of the Lycian Foreland Basin that comprises mainly Eocene to Late Miocene turbidites, onto which the allochthonous Lycian and Antalya nappes thrust over. The Aksu Basin, however, developed in the inner part of the Isparta Angle and is bounded by the Aksu Thrust in the east. During their evolution, these basins experienced significant bathymetric changes, possibly due to vertical motions and variations in the sediment supply. This study provides a detailed analysis of the paleobathymetric evolution of these basins. This conducted paleobathymetric study was based on the determination of the depositional depth by the abundance ratio of planktonic versus benthic foraminifera, which is the function of the water depth. The percentage of planktonic foraminifera relative to the total foraminifer population (%P) increases from shallow to deep water. However, some benthic foraminifera species are directly affected by the oxygen level of the bottom water, rather than by paleobathymetry, i.e. stress markers, and were discarded in the calculation. Additionally, the dissolution of the foraminifera has the potential for miscalculations, since planktonic foraminifera are more prone to dissolution than benthic ones. Nevertheless, the obtained quantitative results were verified and validated qualitatively by specific benthic depth markers that lived at specific depth ranges. Aksu Basin had a shallowing trend, and the sedimentation rate exceeded the subsidence in the middle of the section. Calculated depths for the Gombe Basin indicated depths around 1000 m, which was contrary to the high sedimentation rates indicated by the turbiditic facies of the basin infills.
Paleomagnetic Evidence for Upper Plate Response To a Step Fault, Sw Anatolia
(Elsevier Science Bv, 2018) Kaymakci, Nuretdin; Langereis, Cor; Ozkaptan, Murat; Ozacar, A. Arda; Gulyuz, Erhan; Uzel, Bora; Sozbilir, Hasan
Pliny-Strabo Trench is a Subduction Transform-Edge Propagator (STEP) Fault developed on the northern edge of the subducted African Oceanic Lithosphere. It connects the Aegean and Cyprian trenches in the Eastern Mediterranean convergent system. Although, deep geometry of the STEP fault and associated slab tear in mantle are imaged, its shallow vertical and lateral continuation in the crust and impact on the over-riding plate are still unknown. Thus, we have studied SW Anatolia, the candidate site where this structure could propagate laterally and vertically, for its vertical axis rotations using paleomagnetic tools. In this study, more than 2000 paleomagnetic samples were collected and analysed from 86 different sites which were later classified into 11 separate geographic domains displaying similar tectonic characteristics. Moreover, available paleomagnetic data in the literature were parametrically resampled, analysed and combined with our data. In the region, there is a positive correlation between rotation amounts and sample ages supporting continuous deformation throughout the Neogene period. The spatial variations of results indicated that the study area can be divided into three main domains based on vertical axis rotations. From the south to the north these domains include SW Anatolian domain with similar to 20 degrees counter-clockwise rotation, Burdur-Dinar-Ulubey domain with similar to 4 degrees counter-clockwise rotation and northern areas characterized by clockwise rotations. The identified domains of counter-clockwise rotation are separated by a well-defined NW-SE striking Acipayam Transfer Zone and there is no differential rotation in agreement with the presence of NE-SW striking shear zone in the region. Therefore, we concluded that the Pliny-Strabo STEP Fault have not propagated into the over-riding plate as a shear zone. This implies that there is no evidence to support the presence of alleged Fethiye-Burdur Fault Zone as suggested, and its existence is dubious. (C) 2018 Elsevier B.V. All rights reserved.
Repeated Reactivation of Clogged Permeable Pathways in Epithermal Gold Deposits: Kestanelik Epithermal Vein System, Nw Turkey
(Geological Soc Publ House, 2018) Gulyuz, Nilay; Shipton, Zoe K.; Kuscu, Ilkay; Lord, Richard A.; Kaymakci, Nuretdin; Gulyuz, Erhan; Gladwell, David R.
This study presents a detailed study of the dimensions, geometry, textures and breccias of a well-exposed epithermal vein system, the Kestanelik gold deposit in the Biga Peninsula, NW Turkey, and investigates the permeability enhancement mechanisms in epithermal gold deposits. Here mineralization is associated with quartz veins up to 13.6 m thick. Vein textures and breccia components indicate repeated sealing and subsequent brecciation of wall rock and pre-existing vein infill. Field and petrographic analyses characterize east-west-trending veins as left lateral faults, whereas NE-SW-trending veins are extensional (Mode I) fractures. Cataclasite and tectonic breccia of wall rocks and early quartz, hydrothermal crackle breccias, and matrix-supported chaotic breccias of pre-existing vein infill, all of which are cemented by late iron-oxide-bearing quartz, indicate that co-seismic rupturing and hydraulic fracturing are two major permeability enhancement mechanisms. In addition, transient variations in local stress direction, caused by syn-mineralization dyke intrusion, may have enhanced permeability on misoriented surfaces and at locations where the dip changes. This study emphasizes the importance of understanding structural geology and kinematics as controls on the location of boiling and mineralization mechanisms in epithermal gold deposits.