Reconciling the stratigraphy and depositional history of the Lycian orogen-top basins, SW Anatolia

Terrestrial fossil records from the SWAnatolian basins are crucial both for regional correlations and palaeoenvironmental reconstructions. By reassessing biostratigraphic constraints and incorporating new fossil data, we calibrated and reconstructed the late Neogene andQuaternary palaeoenvironments within a regional palaeogeographical framework. The culmination of the Taurides inSWAnatolia was followed by a regional crustal extension from the late Tortonian onwards that created a broad array of NE-trending orogen-top basins with synchronic associations of alluvial fan, fluvial and lacustrine deposits. The terrestrial basins are superimposed on the upper Burdigalian marine units with a c. 7 myr of hiatus that corresponds to a shift from regional shortening to extension. The initial infill of these basins is documented by a transition from marginal alluvial fans and axial fluvial systems into central shallow-perennial lakes coinciding with a climatic shift from warm/humid to arid conditions. The basal alluvial fan deposits abound in fossil macro-mammals of an early Turolian (MN11–12; late Tortonian) age. The Pliocene epoch in the region was punctuated by subhumid/humid conditions resulting in a rise of local base levels and expansion of lakes as evidenced by marsh-swamp deposits containing diverse fossilmammal assemblages indicating late Ruscinian (lateMN15; late Zanclean) ageWe are grateful for the support of the international bilateral project between The Scientific and Technological Research Council of Turkey (TUBITAK) and The Russian Scientific Foundation (RFBR) with grant a number of 111Y192. M.C.A. is grateful to the Turkish Academy of Sciences (TUBA) for a GEBIP (Young Scientist Award) grant. T.K. and S.M. are grateful to the Ege University Scientific Research Center for the TTM/002/2016 and TTM/001/2016 projects. M.C.A., H.A., S.M. and M.B. have obtained Martin and Temmick Fellowships at Naturalis Biodiversity Center (Leiden). F.A.D. is supported by a Mehmet Akif Ersoy University Scientific Research Grant. T.A.N. is supported by an Alexander-von-Humboldt Scholarship. L.H.O. received support from TUBITAK under the 2221 program for visiting scientists

The stress states acting in the Hatay region [Hatay bölgesinde etkin gerilme durumlari]

In this study, the Plio-Quaternary to present-day stress regimes, acting in the Hatay region, which is located at the northeastern corner of East Mediterranean region, were determined. The modern stress state is obtained from inversion of focal mechanism solutions of shallow earthquakes. The inversion provides that the present-day stress field is dominantly extensional stress regime with NE-trending ?3 axis. The stress regime determined by inversion of slip-vectors measured on active fault planes confirms that the present-day stress regime is extensional in the study area. Both the fault kinematic analysis and the chronology between slip-vectors show that the stress state changed from old strike-slip to younger extensional stress regime consistent with NE-trending ?3 axis. The change between strike-slip and extensional stress regime probably occured during Quaternary time. The both stress regimes, consistent with NE-trending extensional axis (?3), induce left lateral displacement on East Anatolian Fault and Dead Sea Fault directions. The stress regimes prevailing in the Hatay region, result probably from the coeval influence of the boundary forces due to subduction i.e., Cyprus arc, in the southwest and to the thrust zone (Bitlis suture zone) in the northeast. However, we assume that subduction prosess played a dominant role to occurrence of NE-SW extensional stress regime in the Hatay region

Quaternary stress regime change in the Hatay region (SE Turkey)

In this study we determine the Plio-Quaternary to present-day stress regime acting in the Hatay region located at the northeastern corner of the East Mediterranean region. The modern state of stress is obtained from inversion of focal mechanism solutions of shallow earthquakes. This inversion identifies a dominantly extensional stress regime with a NE-trending ?Hmin (?3) axis at the present-day. The stress regime determined from inversion of slip-vectors measured on fault planes confirms that this regime is extensional in the studied area. Both the kinematics and chronologies of fault slip-vectors show that the stress state changed from an earlier strike-slip regime to a younger extensional stress regime with a consistent NE-trending ?Hmin (?3) axis. The change from strike-slip to extensional stress regimes probab y occurred during the Quaternary. Regionally, both stress regimes induce sinistral displacement on the East Anatolian Fault and Dead Sea Fault systems. The North Anatolian Fault (NAF) is a dextral strike-slip fault which runs about 1400 km from east to west and has been active since collision between the Eurasian and Arabian plates. Together with the sinistral East Anatolian fault, the NAF intracontinental deformation zone contributes to the westward extrusion of Anatolia as a consequence of northward drift of Arabia. Consequently, the Late Cenozoic stress regimes acting in the Hatay region result from the coeval influence of forces due to: (1) the subduction processes in the west and southwest; (2) the continental collision in the east, and (3) the westward escape of the Anatolian Block. However, the timing of the temporal stress transition suggests that the Quaternary stress regime change resulted from subduction processes with the extensional stress regime in the Hatay region being mainly attributable to roll-back of the Mediterranean subducted slab along the Cyprus Arc

The changing nature of aminoglycoside resistance mechanisms and prevalence of newly recognized resistance mechanisms in Turkey

ObjectiveTo determine the most frequently occurring individual and combined resistance mechanisms in Gram-negative bacteria resistant to any of the clinically available aminoglycosides in Turkey, and to compare these mechanisms with those found in smaller, earlier studies.MethodsAminoglycoside resistance mechanisms in Gram-negative isolates resistant to either gentamicin, tobramycin, netilmicin or amikacin collected in different regions of Turkey were evaluated both phenotypically and genotypically using 12 aminoglycosides and up to 22 aminoglycoside resistance gene probes.ResultsAmong 696 aminoglycoside-resistant Gram-negative bacteria, resistance rates were very high for gentamicin (94.5%), tobramycin (82.4%), netilmicin (53.6%), and amikacin (49.7%). Although isepamicin was the most active aminoglycoside against Gram-negative bacteria, increased resistance (29.7%) was found and resistance rates were higher than those in most of the other countries surveyed in earlier studies. The most common aminoglycoside resistance mechanisms (AAC(3)-II (GTN), AAC(6')-I (TNA), and ANT(2”)-I (GT)) in the earlier studies were also found in the present isolates of Klebsiella spp., Enterobacter spp. and Escherichia coli, with increased complexity. In addition to these old mechanisms, two new aminoglycoside resistance mechanisms, namely AAC(6')-III (TNAI) and AAC(6')-IV (GTNA), were also found at significant frequencies (11.9% and 26.9%, respectively) in these isolates of Enterobacteriaceae (n = 435). Among the isolates of Pseudomonas spp. (n = 150), in addition to the increased complexity of enzymatic resistance mechanisms (AAC(3)-I (16.6%), AAC(6')-II (29.3%), AAC(6')-III (19.3%), ANT(2”)-I (40%)), permeability resistance seemed to be responsible for the high rates of resistance to aminoglycosides.ConclusionThe results of this study indicated increased resistance to clinically available aminoglycosides, including isepamicin, even though it was the most active, as a result of both the presence of new aminoglycoside resistance mechanisms and the increased complexity of all mechanisms, including permeability resistance, particularly in Pseudomonas in Turkey

Plio-Quaternary Stress State in the Burdur Basin, SW-Turkey

This study defines the Plio-Quaternary to present day stress regime in the Burdur Basin, located at the northeastern end of the Fethiye-Burdur Fault Zone in SW Turkey. This fault length, which is considered the landward continuation of the Pliny-Strabo trench, is an important feature in SW Turkey. The inversion slip vectors measured on fault planes indicate a consistent normal faulting stress regime during Plio-Quaternary time, continuing into recent times as indicated by earthquake focal mechanism inversions. Both states have consistent NW-SE trending horizontal minimum stress axes (?3). The orientation of fault sets is predominantly around the NE-SW direction in the major Fethiye-Burdur Fault Zone, making the extension NW-SE. The mean stress ratio is 0.74 indicating a triaxial stress state, which is clearly different from radial extension. The NW-SE extension is probably responsible for the formation of the Burdur Basin during Plio-Quaternary time. This extension, which is probably caused by slab-pull force due to the subduction process along the Cyprus arc, produces a dominant normal motion along the FBFZ. © 2013 Elsevier B.V.107Y321This work was financially supported by TUBITAK-ÇAYDAG (Project no: 107Y321 ). The authors would like to thank Catherine Yiğit for assistance with English exposition that improved recent version of the text. The authors are also grateful to the anonymous reviewers for their valuable comments and suggestions that greatly improved the quality of the manuscript

Plio-quaternary stress regime in Eşen Çay Basin, SW Turkey

The Plio-Quaternary Eşen çay Basin is situated at the junction of Hellenic and Cyprus arcs in southwestern Turkey. The basin is important for understanding the tectonic evolution of the region in relation to the Hellenic and Cyprus arcs. Fault data from unconsolidated Pliocene and Quaternary deposits, as well as from pre-Pliocene lithologies, areanalysed in order to reconstruct the evolution of the stress field evolution from Pliocene onwards. Inversion of measured fault slip vector data identifies two main stress states: extensional and strike-slip. Both states are characterized by a NE-SW-trending minimum horizontal stress axis (?Hmin = ?3). The mean R value is 0.67, indicating a triaxial state of stress. The inversion also indicates the existence of extensional and strike-slip faulting characterized by a NW-SE-trending ?3 axis. This indicates a change in the direction of the minimum horizontal stress axis (?3) from a NW-SE-trending ?3 that dominated prior to Quaternary to a NE-SW-trending ?3 that dominated during Quaternary up to actual time. © The Geological Society of London 2013

Upper crust response to geodynamic processes beneath Isparta Angle, SW Turkey: Revealed by CMT solutions of earthquakes

The Isparta Angle is an important area of SW Anatolia where extensions in all directions (N-S, NE-SW, NW-SE and E-W) meet. These extensions were determined by normal faulting structures as well as by shallow earthquakes. All extensions, except the E-W one, were attributed to the deviatoric stresses in relation to slab forces and/or extrusion of Anatolia. The moment tensor inversion of 40 shallow earthquakes which occurred in the inner part of the Isparta Angle give focal mechanisms mostly indicating normal faulting. Inversion of all focal mechanisms of the earthquakes obtained from the moment tensor inversion yields normal faulting characterized by an approximately E-W (N268°E) ?3 axis. The calculated stress ratio R is 0.6944 indicating a triaxial stress state. Commonly accepted geodynamic models for the eastern Mediterranean region do not include plate boundary forces acting in the east or west direction. Our hypothesis is that the cause of the E-W extension is the combined forces of Gravitational Potential Energy and the hot asthenosphere upwelling through a tear fault in the subducted African plate between the Hellenic and Cyprus arcs beneath the Isparta Angle. © 2016 Elsevier B.V.107Y321This work was financially supported by TUBİTAK-ÇAYDAG (Project no: 107Y321 ). The authors would like to thank Catherine Yiğit for assistance with English that improved a recent version of the text. The authors are also grateful to the anonymous reviewers for their valuable comments and suggestions that greatly improved the quality of the manuscript

Late Cenozoic stress state distributions at the intersection of the Hellenic and Cyprus Arcs, SW Turkey

The history of the Late Cenozoic stress regime was determined for an area between the gulfs of Fethiye and Antalya. Fault kinematic analysis and inversion of focal mechanisms of shallow earthquakes reveal significant evolution of the regional stress regime in SW Anatolia, i.e., the area of interaction between the Hellenic and Cyprus arcs, from the Mio-Pliocene to the present time. Fault kinematic analysis yields two different normal faulting stress regimes along the southwestern part of Fethiye-Burdur Fault zone, e.g., in and around Çameli Basin (Zone A1) and two different strike-slip to normal faulting stress regimes characterized by a roughly orthogonal set of extensional axes between Fethiye and Demre (Zone B) with an older NW–SE ?3 axis for Mio-Pliocene and a younger NE–SW ?3 axis for Plio-Quaternary time. Inversion of focal mechanisms of the earthquakes occurring in Zone A1 provides an extensional stress state with approximately N-S ?3 axis. Inversion of those occurring in Zone B, south of Zone A1, yields a dominantly strike-slip stress state with a NE-SW ?3 axis and a NW-SE ?1 axis respectively. The inversion slip vectors from fault planes yield a consistent normal faulting stress regime in Burdur Basin and its surroundings (i.e., along the northeastern part of Fethiye-Burdur Fault Zone, (Zone A2)) during Plio-Quaternary, continuing into recent time as indicated by earthquake focal mechanism inversions. Both states have a consistent NW–SE ?3 axis. Fault kinematic analysis indicates NW-SE extension acting in Zone C (subarea between Demre and Antalya), south of Zone A2, during Mio-Pliocene time. The inversion of focal mechanisms yields normal faulting also characterized by a consistent NW-SE ?3 axis. The nearly orthogonal extensional stress regimes (NW-SE and NE-SW) obtained by inversion of both measured and seismic faults seem to have been acting contemporaneously with each other at different intensities from the Mio-Pliocene onwards in SW Turkey. This may be attributed to the geodynamic effects related to the subduction of the African plate beneath Anatolia diffusing along the Hellenic and Cyprus arcs and in the west-southwestward extrusion of Anatolia. The cause of the early NW–SE extension is the slab-pull force due to the subduction process along the Cyprus arc, considered to be dominant until the Plio-Quaternary in the western part of the study area in zones A1 and B. The dominant status of the Cyprus arc continues today in the eastern part of study area in zones A2 and C. The later NE–SW to present day approximately N–S extension, dominant since the Plio-Quaternary, is related to the combined forces of the Anatolian extrusion and the subduction process along the Hellenic arc. © 2016 Elsevier Ltd107Y321This work was financially supported by TUBİTAK-ÇAYDAG (Project no: 107Y321 ). The authors would like to thank Catherine Yiğit for assistance with English that improved a recent version of the text. The authors are also grateful to the two anonymous reviewers for their valuable comments and suggestions that greatly improved the quality of the manuscript