development of the kembos and eynif structural poljes morphotectonic evolution of the upper manavgat river basin central taurides turkey abstract the study area is the upper manavgat river basin it is located in the western part of the central taurides two significant geomorphic features of this basin are the kembos and eynif structural poljes this study focuses on the tectonic impacts on the development of poljes and the morphotectonic evolutionary history of the study region the data were obtained through a detailed mapping of the faults rocks and geomorphic features the evolutionary history of the basin begins with the nw se trending karstic paleovalleys which first formed on the erosional surfaces that are part of the early and middle miocene contractional tectonic regime the tributaries which developed under the influence of the nw se trending pliocene strike slip faults joined the main trunk of the manavgat river starting at the beginning of the quaternary the tensional tectonic regime became prominent and then a series of graben horst structures appeared the eynif and kembos poljes formed within two of these structures the underground capture of surface water occurred in the grabens the waters of both poljes drain through swallow holes into the manavgat river and then in to the mediterranean sea the regional uplift rates the downcutting rates are as follows 0 36 mm y in the late miocene tortonian messinian 0 06 mm y in the pliocene and 0 18 mm y in the quaternary periods which are based on the geopmorphic data obtained from high erosional surfaces and the manavgat river valley the average downcutting uplift rate is 0 18 mm y in this region

late quaternary landscape evolution in the atlantic plateau brazilian highlands tectonic and climatic implications of fluvial archives abstract this paper identifies and discusses the major phases of relief evolution resulting from fluvial processes during the late quaternary in the quadrilatero ferrifero qf region atlantic plateau and contextualises them as strong indicators of the past tectonic and climatic influences on landscape evolution in the brazilian highlands seven regional phases of fluvial level development terraces and modern floodplains were identified based on geomorphological and stratigraphic aspects and dated between 83 ka and the present although older records occur in some valleys up to 140 ka they are poorly preserved and therefore ambiguous in interpretation river valleys in the qf are generally narrow and deeply dissected favouring intense erosion processes thus inhibiting the preservation of early and middle quaternary fluvial archives most of the seven phases identified were followed by periods of river downcutting into bedrock however river incision rates vary significantly and indicate that the paraopeba river catchment belongs to a more active tectonic block there was an association of the regional phases with climatic oscillations that may have influenced the rhythms of the fluvial incision driest coldest periods were marked by the formation of fluvial depositional successions with duricrusts repeated formation of terraces with conglomeratic duricrusts may be related to lower rates of river incision in some valleys some other factors such as the existence of knickpoints the size of each river catchment and its position in the regional river system trunk river or tributary as well as in the regional tectonic arrangement may have influenced the capacity of the rivers to respond differently to the same climatic and tectonic regional events

a case for a downwasting mountain glacier during termination i vercenik valley northeastern turkey field evidence of palaeoglacial records in the vercenik valley in the eastern black sea mountains was examined and 19 samples for surface exposure dating with cosmogenic 10 be were collected with the aim of increasing knowledge on the amplitude and frequency of palaeoglacier advances in anatolia glacial erosional features were mapped and the flow directions of the palaeoglaciers were determined the vercenik palaeoglacier advanced before 26 1 k 1 2 k yr the last glacial maximum lgm advance continued until 18 8 k 1 0 k yr the vercenik palaeo glacier collapsed during termination i after 17 7 k 0 8 k yr there was no more ice in the main valley the vercenik palaeoglacier most probably then separated into five small glaciers that were restricted to the tributary valleys among these the hemsin palaeoglacier completed its recession around 15 7 k 0 8 k yr on the basis of glacial erosion features a lateglacial glacier advance can be identified evidence of the little ice age advance appears to be absent the results from this valley system seem to be consistent with the first results from the adjacent kavron valley and with the anatolian lgm palaeoclimate the sea surface temperature minima in the western mediterranean the deposition of red clay layers in the black sea and deposition of the heinrich 1 layer in the north atlantic copyright 2007 john wiley sons ltd

stratigraphy and age of the cappadocia ignimbrites turkey reconciling field constraints with paleontologic radiochronologic geochemical and paleomagnetic data the stratigraphy and age of the neogene cappadocia ignimbrites central turkey have been inferred in previous studies from fieldwork and k ar age determinations the resulting stratigraphic schemes however differed from each other suggesting that further studies were required to produce a reliable succession in this paper we examine the chronostratigraphy of mammalian remains recovered in the continental sediments interbedded with the cappadocia ignimbrites using recent advances in mammalian chronostratigraphy we evaluate selected taxa and faunal associations to place new and independent constraints on the ignimbrite ages the biostratigraphically bracketed ages concur with some published radiometric dates but they disagree with others principally at localities where major stratigraphic discrepancies have arisen in the literature in order to reconcile these apparent inconsistencies we combine at selected sites our field observations with the biostratigraphic and radiometric age limits and we compare these with the available geochemical and magnetic data this allows us to present revised age estimates and a revised stratigraphy which includes the correlation of the local sofular deposits with the large volume gordeles ignimbrite the issues faced in this study apply to other ignimbrite provinces in the world for instance ignimbrite eruption frequency in cappadocia is higher than the resolution of many published k ar ages furthermore different k ar ages have led to the description of individual and distinct ignimbrites that fieldwork and geochemical data allow to merge into a single ignimbrite argon loss from pumice samples leading to radiometric rejuvenation provides a likely explanation for most stratigraphic discrepancies cappadocia is the only documented ignimbrite field in which the chronostratigraphy of vertebrate remains provides better constraints on some ignimbrite ages than scattered k ar dates we further argue that k ar dates from the cappadocia area are too imprecise to establish a reliable magnetostratigraphic scheme for the ignimbrite succession with the exception of the not vert similar2 8 ma valibaba tepe ignimbrite

fluvial response to climate change during and after the last glacial maximum in central anatolia turkey abstract fluvial response to climate change during and after the last glacial maximum lgm included incision aggradation phases recorded in sediment cores from the valley floor of the kizilirmak in central anatolia a numerical chronology was established by ams dating of fluvial sediments and ar ar dating of a basalt sample capping the youngest terrace late pleistocene terrace indicating that the main incision phase was completed at the end of the lgm the succeeding aggradation phase in the valley took place from the end of the lgm onwards it appears that the major climatic transition from the lgm to the late glacial gave rise to aggradation in the fluvial system and this event seems to be consistent with the timing of the regression phase of pluvial lakes and the termination of paleoglacier advances in the high mountains of anatolia this study of fluvial systems in anatolia indicates that the coldest periods are not always characterized by fluvial aggradation

the obliquity controlled early pleistocene terrace sequence of the gediz river western turkey a revised correlation and chronology the buried early pleistocene river terrace record of the gediz river around kula western turkey has previously been considered to span the time interval equivalent to marine isotope stages mis 58 37 c 1 6 1 2 ma with the frequency of terrace formation mirroring obliquity driven climate change whereas progressive pleistocene incision of the gediz river is seen as a response to regional uplift the timing of fluvial incision leading to terrace formation and subsequent new floodplain development is believed to be climate controlled with incision deposition cycles resulting from varying sediment discharge conditions a direct consequence of changing climate and related vegetation change new outcrop observations downstream of the original field area alongside recently published geochronological data and improved understanding of the volcanic sequence all now suggest that the previously published interpretation is incorrect here we present a revised stratigraphy based upon terrace gradients of c 0 004 0 005 previously 0 001 in which 11 terraces are identified but only terraces gt11 the oldest to gt6 pre lava incursion predate volcanism the available geochronology suggests that terraces gt6 post first lava incursion to gt1 relate to the time interval mis38 28 c 1 26 1 ma however despite penecontemporaneous volcanism terrace formation continues to reflect sediment discharge changes predominantly controlled by regional climate change

chronology of the yellow river terraces at qingtong gorge ne tibet insights into evolution of the yellow river since the middle pleistocene abstract the formation and abandonment of fluvial terraces provide key records of past climatic changes and regional tectonics that reflect the evolution of rivers at the northeastern periphery of the tibetan plateau the yellow river flows through the qingtong gorge a deep canyon incised through the niushou shan a flight of 8 fluvial terraces preserved along the canyon four of which t2 t3 t6 and t8 were dated using osl and cosmogenic nuclide exposure dating the results show that the four terraces were formed at 51 6 2 9 ka 60 7 14 4 8 3 ka 346 1 30 27 3 ka and 580 640 ka respectively precise measurement of terrace heights suggests that the average incision rate of the yellow river over the past 350 ka was 200 m ma and increased significantly in the past 60 ka analysis of the relationship between the observed incision histories with regional climatic records and local tectonics suggests that climatic variations since the late quaternary drove cutting and abandonment of the terraces during progressive tectonic growth of the niushou shan our results provide constraints on the timing of incision and linkage of various segments of the modern yellow river fluvial network

vent distribution and its relation to regional tectonics cappadocian volcanics turkey abstract the distribution of polygenetic and monogenetic volcanoes of the neogene quaternary cappadocian volcanic province cvp is analyzed to investigate the relationship between vent location and regional tectonic lineaments two fault systems exist in the province one system miocene quaternary tuzgolu ecemis system is oblique whereas the other system late miocene pliocene cvp system is parallel to the long axis of the cvp the polygenetic volcanoes are aligned parallel to the second system but concentrate around the major faults of the first system regional offsets are proposed along the first fault system based on the distribution of the polygenetic volcanoes the monogenetic volcanoes group into five geographically distinct clusters in the western part of the cvp the monogenetic cones are aligned parallel to the cvp system whereas in the central part the cones are fed by dikes injected along the recent fractures of the tuzgolu ecemis system in the eastern part the monogenetic cones form along the radial fractures of the erciyes composite volcano

volcanological evolution of mount erciyes stratovolcano and origin of the valibaba tepe ignimbrite central anatolia turkey abstract mount erciyes 3917 m is the largest stratovolcano of central anatolia turkey the volcanological evolution of mount erciyes from pliocene quaternary to historical times exhibits two distinct stages 1 koc dag and 2 erciyes during the koc dag stage basaltic and andesitic lava flows were emitted from the cinder cones of kizil tepe and topakkaya tepe then koc dag pyroclastics were emplaced leading to a caldera collapse of 14 18 km in diameter with a volume estimated at 110 km3 two eruption phases separated by scoria fall and mud flow deposits are recognised associated with the caldera forming event during phase 1 plinian fall and pumice flows were emplaced on the eastern part of the volcano plinian fall deposits occur more than 50 km away from the source area the volume of tephra is estimated at 63 3 km3 16 km3 dense rock equivalent dre including 62 km3 of plinian fall and 1 3 km3 pumice flow deposits phase 2 mainly consists of pyroclastic flow deposits two pumiceous flow units and valibaba tepe ignimbrite vti the pumiceous flow deposits 4 2 km3 dre extend 30 km from the inferred source area towards the north and northeast the final pyroclastic flows of phase 2 occurred 2 8 ma ago and produced the vti the vti is a low aspect ratio welded ignimbrite and its volume is estimated at 40 km3 dre plinian fall deposits 0 8 km3 dre preceded the vti and are only observed on the eastern part of the volcano covering an area of 1500 km2 during the erciyes stage two eruptive cycles are defined the first cycle 2 6 0 17 ma is characterised by effusive extrusive and weakly explosive activity with emplacement of andesitic lava flows dacitic dome flows basaltic andesite lava flows and andesitic cones the second cycle involved dacitic extrusive and explosive activity located at the summit area and produced block and ash flows derived from rhyodacitic domes plinian fall surge and pumice flow deposits were emplaced prior to rhyodacitic dome extrusions the last event was the emplacement of debris avalanche deposits related to sector collapse caldera

paleoglacial records from kavron valley ne turkey field and cosmogenic exposure dating evidence abstract kavron valley lies in the kackar mountain range of northeastern anatolia and is a north south oriented typically u shaped glacial valley consisting of a main and three tributary valleys the quaternary units that outcrop in this valley have been mapped and 22 samples have been processed for surface exposure dating using cosmogenic 10 be according to the 10 be ages the advance of the kavron paleoglacier began at least 26 0 1 2 kyr ago with the last glacial maximum lgm advance continuing until 18 3 0 9 kyr after this time the kavron paleoglacier receded although the magnitude of this recession is still unknown subsequent to this retreat the glacier most probably separated into three smaller glaciers that were restricted to the tributary valleys ifrit derebasi and mezovit paleoglaciers the main valley was definitely ice free by 15 5 0 7 kyr ago with the mezovit paleoglacier completing its recession around 15 5 0 6 kyr a late glacial advance took place around 13 0 0 8 to 11 5 0 8 kyr and little ice age moraines appear to be absent our results from the kavron valley system seem to be consistent with the lgm paleoclimate record of anatolia which has been delineated by data gathered from lowlands and lakes the deposition of red clay layers in the northwestern black sea and the deposition of heinrich 1 layers in the north atlantic

river terrace systems in north west europe an archive of environmental change uplift and early human occupation abstract staircases of large scale aggradational river terraces are a notable feature of many valleys in the temperate lattitudes particularly in areas beyond the reach of the erosive activities of pleistocene ice sheets it is now recognized that the cyclic fluctuations of climate during the quaternary have driven the generation of terraces through the direct and indirect influence of both temperature and precipitation on fluviatile activity where fossiliferous deposits are preserved within terrace sequences it is often possible to date these and to correlate them with the oceanic record thus providing an important framework for the evidence of environmental change on land middle and late pleistocene terraces in different areas can commonly be seen to have formed in synchrony with glacial interglacial cycles or with longer periodicity megacycles climatic forcing alone is insufficient to cause terraces to form however uplift is also necessary so that terrace sequences can provide a useful record of crustal movement in northwest europe where some of the best known studies of river terrace sequences have been carried out the fluviatile deposits are also an important repository for palaeolithic artefacts from which a record of early human occupation can be reconstructed

cold and wet last glacial maximum on mount sandiras sw turkey inferred from cosmogenic dating and glacier modeling abstract in situ cosmogenic 36 cl was measured in boulders from moraines on mount sandiras 37 1 n 28 8 e 2295 m the southwestern most previously glaciated mountain in turkey valleys on the north side of the mountain were filled with 1 5 km long glaciers that terminated at an altitude of 1900 m the glacial activity on mount sandiras correlates with the broadly defined last glacial maximum lgm the maximum glaciation occurred approximately 20 4 1 3 ka 1 1 ka 1000 calendar years ago when glaciers started retreating and the most extensive moraines were deposited the glaciers readvanced and retreated by 19 6 1 6 ka ago and then again by 16 2 0 5 ka using the glacier modeling and the paleoclimate proxies from the eastern mediterranean we estimated that if temperatures during lgm were 8 5 11 5 c lower than modern precipitation was up to 1 9 times more than that of today thus the local lgm climate was cold and wet which is at odds with the conventional view of the lgm as being cold and dry in the region

morphotectonic evolution of mavibogaz canyon and sugla polje sw central anatolia turkey abstract this study focuses on the morphotectonic evolutionary history of two significant geomorphic features sugla structural border polje and mavibogaz canyon located within the sugla seydisehir akoren kavakkoy and bozkir grabens in the central taurides data were obtained by detailed field mapping of faults rocks and geomorphic features three phases of tectonic deformation were determined the three erosional surfaces developed especially in the form of tectonically controlled steps during oligocene early miocene middle miocene and late miocene early pliocene sequentially southwest to northeast trending karstified hanging paleovalleys are present on the high erosional surfaces which have been attributed to the end of early miocene and late miocene faulting induced tectonic movements enabled the formation of sugla seydisehir paleograben in early miocene we suggest that the mavibogaz canyon was formed by captures at the beginning of late miocene and late pliocene and by incision in late pliocene quaternary depending on the headward erosion of carsamba river starting from the beginning of quaternary a tensional neotectonic regime became prominent and then a series of modern graben horst structures formed along the reactivated older grabens one of these is the sugla seydisehir reactivated graben sugla structural border polje developed within the graben total visible tectonic subsidence of the polje is 134 m underground capture of surface water occurred on the southern slopes of the graben waters of sugla polje are transported intermittently into konya basin on the surface and into the mediterranean basin via natural swallow holes beach deposits water marks cliffs and notches marking the late pleistocene lake level 10 m and two perched corrosion surfaces 50 and 22 m were detected around the polje

geochemical features of collision related volcanic rocks in central and eastern anatolia turkey in central and eastern anatolia volcanism related to continental collision occurred in neogene to quaternary times major and trace element compositions 87sr86 sr and k ar ages were determined for volcanic rocks from selected volcanoes in this region 87sr86 sr for basalts from erciyes volcano in the eastern part of central anatolia as well as ararat nemrut and karacadag volcanoes in eastern anatolia are in the range 0 7035 0 7040 these ratios are higher than those of n type morb but overlap arc volcanic rock values this suggests that the mantle source which was possibly contaminated by fluids and melts with higher87sr86 sr during the pre collisional events has similar sr isotopic compositions in wide areas of the eastern part of central anatolia and eastern anatolia even across the collision plate boundary in addition chemical compositions of the mantle source are not homogeneous with respect to hfs element contents indicating that the slab derived components resulting from past subductions are not homogeneously distributed the mantle source beneath the western part of central anatolia which corresponds to the transitional region from collision tectonics in the east to subduction tectonics in the west has different chemical and sr isotopic signatures from other parts of anatolia in the western part of central anatolia the87sr86 sr of basaltic rocks from three regions characterized by monogenetic volcanoes are in the range 0 70427 to 0 70581 and differ from region to region in spite of indistinguishable chemical compositions this indicates either source heterogeneity on a small scale or different contributions of local crustal contaminants calc alkaline lavas from ararat and kars in eastern anatolia have chemical compositions with subduction signatures inherited from pre collision subduction events in contrast the chemical and sr isotopic features of volcanic rocks from erciyes volcano in central anatolia indicate that the combined process of fractional crystallization of basaltic magma and crustal assimilation without injection of slab derived components is the dominant process generating calc alkaline andesite under the collision tectonics regime operating in this region

dating quaternary volcanism and incision by the river tigris at diyarbakir southeast turkey new high precision ar ar dating of basalt underlying the city of diyarbakir southeast turkey constrains the quaternary incision history of the river tigris strengthening the pre existing chronology based on magnetostratigraphy and k ar dates the basalt which overlies tigris terrace gravel 70 m above the river is part of the karacadag shield volcano complex centred ca 60 km to the southwest the reverse magnetised diyarbakir basalt one of relatively few flow units to reach the tigris valley axis has been dated to 1196 19 ka 2 two lower terraces have been recognised in the diyarbakir area 46 and 32 m above the present river with at least one other further downstream from this evidence the rate of middle late pleistocene incision by the tigris can be estimated it probably reached ca 0 07 mm a 1 reflecting the characteristic global increase in uplift rates observed at that time copyright 2007 john wiley sons ltd

slow stick slip of antigorite serpentinite under hydrothermal conditions as a possible mechanism for slow earthquakes slow earthquakes characterized by a different scaling law to regular earthquakes have been detected at the hydrated plate interface in the subduction zones but the generating mechanism of them remains almost unexplored frictional experiments on antigorite serpentinite under hydrothermal conditions are conducted to assess the distinct scaling law of slow earthquakes slow stick slip was observed at temperatures that were close to the dehydration temperature of antigorite which is resulted by the localized dehydration of serpentine in the shear zone the occurrence of slow stick slip is consistent with the temperature range found in the corner of the mantle wedge in sw japan and cascadia where slow earthquakes occur the laboratory slow stick slip shows a similar scaling law of slow earthquakes but distinct from that of regular earthquakes we propose that the shear induced dehydration of the serpentine play an important role for the generation of slow earthquakes

semi brittle deformation of antigorite serpentinite under forearc mantle wedge conditions abstract serpentinization of the mantle wedge immediately above a subducting slab is a key process controlling the strength contrast between the slab and the overriding nominally anhydrous i e olivine rich mantle to assess the influence of serpentinite rheology on the degree of decoupling between the slab and mantle wedge we conducted axial compression tests on partially foliated antigorite serpentinite using a modified griggs type apparatus at confining pressures pc of 1 0 2 5 gpa temperatures t of 300 600 c and a strain rate of 1 5 10 5 s 1 with increasing temperature the dependence of maximum differential stress i e strength on pc changes from positive to flat suggesting an increasingly important contribution from plastic deformation microstructural observations show that increasing temperature promotes a transition in deformation mechanisms from distributed inter and intra granular microcracking to comminution and kinking localized within a through going shear zone the ductile to brittle transition can be attributed to the operation of thermally activated processes such as dislocation glide and grain boundary sliding in aligned antigorite grains comparison with strength data for dunite demonstrates that in the semi brittle regime the strength contrast between antigorite and olivine is

river incision and terrace formation in the late cenozoic of europe abstract late cenozoic environmental changes which affected european rivers are reviewed focusing especially on those of mid pleistocene times c 1 2 0 8 ma or around mis 22 and thereafter these involved dominating but fluctuating cold climate periglacial conditions shorter but major episodes of glaciation and brief interglacials there were also related sea level and tectonic responses the known history of european rivers in this period is individually varied but is predominantly marked by multiple stages of episodic incision the form of which changed in style at around the mid pleistocene transition it is suggested that the nature of climatic oscillations the dating of incision episodes and the processes that achieve this incision are as yet insufficiently understood fluvial process studies suggest that the onset of incision may broadly relate to changes in slope discharge sediment load and calibre and bedrock erodibility and these may all have been transformed as the direct or indirect result of mid pleistocene climatic changes common properties of basal sediments on strath terraces suggest that it was during the extended but variable cold stage episodes that both valley deepening and lateral widening occurred and that climatic change was the principal driver of episodic deep valley incision

cause and effect in mediterranean erosion the role of humans and climate upon holocene sediment flux into a central anatolian lake catchment abstract the debate in historical geomorphological studies about the causes of erosion in regions such as the mediterranean has been long standing the relative roles of climate change and human impacts can be difficult to disentangle in the absence of highly resolved chronologies here we reconstruct the erosion history of a small lake catchment in central anatolia located on the edge of one of the mediterranean s most iconic badland landscapes in cappadocia because these lake sediments are annually laminated precisely dating clastic inwash layers and calculating recurrence intervals and flux rates is possible lake cores have been analysed for xrf elemental geochemistry and via thin sections along with proxies for hydroclimate oxygen isotopes and land cover pollen peaks in titanium along with other detrital elements and changes in clastic layers indicate increased sediment influx into nar lake between 9300 and 8000 cal bp ceramic neolithic when obsidian mining took place nearby and again more importantly during the last 2500 years iron age to modern the latter exhibiting three phases of enhanced catchment erosion multiproxy comparisons show that these phases were related primarily to periods of increased human impact on vegetation and soils around the lake most sediment influx has been in the form of turbidites linked to the presence of a fan delta at the lake edge although this store does not appear to have significantly delayed sediment delivery from eroding hillslopes to the lake bed the marked increase in detrital influx during the late holocene implies that badland development in the lake catchment is recent and largely anthropogenic rather than ancient and of climatic causation and probably involving stream capture the record also shows that sediment influx diminished markedly at times when human land use disintensified which in turn indicates that hillslope degradation is reversible with appropriate land management

environmental and climatic changes during the last 20 000 years at lake tuz central turkey abstract our study demonstrates the importance of detailed lithostratigraphic and biostratigraphic analyses of deposits of lake side terraces and alluvial fans in attempts to identify fluctuations of climate characteristics such as precipitation and evaporation rates and of local conditions for water balance changes in the central part of turkey during the last 20 000 years lake tuz basin central part of the anatolian plateau turkey had two high lake level stages dated as about 20 000 17 000 years ago and about 13 000 years ago at the high lake stages water level rose more than 15 m higher than the present lake level and the lake area spread widely to near the southern edge of the basin as inferred by lithologic and chronological investigation of drilling cores in the holocene lake level fell and the southeast part of the basin became extensive lake terraces alluvial fans have formed along the edge of the upland area on the terraces in the holocene stratigraphy and dating of the fan deposits show the fluctuations in the depositional rates of the fans major formative stages of the fans are dated about 7000 5500 and 2500 2000 years bp and several times of minor stages probably 4300 and 3000 years bp occurred between the two major stages our archaeological research shows that there are strong relationships between the distributions of archaeological sites of this area and the above geo environmental histories

seismic attenuation beneath northeastern japan constraints on mantle dynamics and arc magmatism we apply a three step approach to estimate three dimensional 3 d p wave attenuation qp 1 structure beneath northeastern japan first corner frequencies of earthquakes are determined using the spectral ratio method for s coda waves then whole path attenuation terms t and site amplification factors are simultaneously estimated by a joint inversion the set of t is finally inverted for 3 d attenuation structure the results show that the mantle wedge has low attenuation in the fore arc and high attenuation in the back arc a depth profile of qp 1 in the back arc mantle is explained by attenuation expected for a two dimensional 2 d thermal model with qp qs 2 and grain sizes of 1 and 3 cm however an inclined high attenuation zone observed in the back arc mantle wedge which is interpreted as an upwelling flow shows higher attenuation than that calculated from the 2 d thermal model the higher seismic attenuation is probably caused by the concentration of partial melt in the upwelling flow a combined interpretation of seismic attenuation and velocity structures further suggests that the degree of partial melt in the upwelling flow varies along the arc and that volcanoes are clustered transverse to the arc below which the upwelling flow contains a higher degree of melt these observations indicate that magmatism is controlled by a mantle wedge process that depends strongly on spatial variations in the degree of partial melt in the upwelling flow our results further imply the breakdown of hydrous minerals in a hydrous layer above the pacific plate at a depth of 120 km

late pleistocene intraplate extension of the central anatolian plateau turkey inferences from cosmogenic exposure dating of alluvial fan landslide and moraine surfaces along the ecemis fault zone here we documented the vertical displacement slip rate extension rate and geochronology of normal faults within a narrow strip along the main strand of the ecemis fault zone the kartal cevizlik and lorut faults are normal faults that have evident surface expression within the strip terrestrial cosmogenic nuclide geochronology revealed that the kartal fault deformed the 104 2 16 5 ka aged alluvial fan surface and the cevizlik fault deformed the 21 9 1 8 ka old moraine and talus fan surfaces our topographic surveys indicated 120 10 m and 13 1 1 4 m surface breaking vertical displacements along the kartal and cevizlik faults respectively accordingly we suggest a 1 15 0 21 mm a 1 slip rate and 0 66 0 12 mm a 1 extension rate for the last 104 2 16 5 ka on the kartal fault and a 0 60 0 08 mm a 1 slip rate and 0 35 0 05 mm a 1 extension rate for the last 21 9 1 8 ka on the cevizlik fault we believe that these structures are an integral part of intraplate crustal deformation in the central anatolia they imply that intraplate structures such as the ecemis fault zone may change their mode through time presently the ecemis fault zone has been deformed predominantly by normal faults the presence of steep preserved fault scarps along the kartal cevizlik and lorut faults point to surface breaking normal faulting away from the main strand and particularly signify that these structures need to be taken into account for regional seismic hazard assessments

late cenozoic surface uplift revealed by incision by the river euphrates at birecik southeast turkey incision by the river euphrates has created a dramatic erosional landscape in the northern arabian platform in se turkey we obtain accurate heights of its terrace deposits in the birecik area using differential gps and summarise evidence regarding heights of late miocene basalt flows and low altitude wetland sediments we thus estimate 600 m of uplift since the early late miocene 9 ma represented by 270 m of fluvial incision the difference reflecting downstream channel lengthening as the coastline has retreated to the persian gulf 1400 km away the oldest recognised sediments inset below this level form a thick aggradation between 100 and 130 m above the present level of the euphrates we estimate that this accumulated during 5 3 ma when uplift rates were low such that aggradation was necessary to maintain a downstream channel gradient in response to the coastal retreat palaeolithic artefacts have been reported locally in euphrates deposits up to 80 m above present river level which we tentatively date to 1 8 ma the euphrates subsequently incised to within 10 m of its present level before aggrading 45 m higher in the late early pleistocene the final 55 m of incision reflects the increase in uplift rates observed worldwide in the early middle pleistocene following the mid pleistocene revolution

paleomorphology of the northwestern of the quadrilatero ferrifero central brazil stratigraphic and geochronological evidence of a pleistocene alluvial fan system abstract this paper presents data on the fragments of ancient sedimentary deposits placed around the piedade and casa branca streams important right bank tributaries of the paraopeba river from these data it was possible to establish a picture regarding the paleomorphology and paleodrainage of the area the methodological steps adopted consisted of the definition of sedimentary facies as well as the establishment of their sedimentary provenance u pb method in detrital zircons and deposition age osl in quartz through the facies analyses it was possible to show channel facies gt associated with debris flows gmm and sieve deposits gh in the sedimentary provenance stage spectra of ages congruent with those found in literature for the moeda and caue formations were identified suggesting that the moeda mountain range is a source area we also analyzed data on the sediments of the current bed which indicate the same provenance showing that the current courses constitute an embedded analog of the paleochannels the data herein obtained corroborate the hypothesis that the eastern periphery of the bonfim complex was dominated by a system of alluvial fans between 9 5 1 and 15 5 1 6 ka before present whose remnants are preserved on the current hilltops and mid slopes of the basement landscape

late pleistocene evolution of the rhine meuse system in the southern north sea basin imprints of climate change sea level oscillation and glacio isostacy high resolution continuous core material geophysical measurements and hundreds of archived core descriptions enabled to identify 13 late pleistocene rhine meuse sedimentary units in the infill of the southern part of the north sea basin the netherlands northwestern europe this sediment record and a large set of optical stimulated luminescence dates 14c dates and biostratigraphical data allowed to establish detailed relationships between climate change sea level oscillation glaciation history and the sedimentary development of the rhine fluvial system during the last glacial cycle marine isotope stages 5e 2 eemian weichselian a well preserved eemian sediment record was encountered as the infill of a late saalian mis6 subglacial basin part of this record reflects groundwater rise controlled fine grained sedimentation as a result of postglacial early eemian sea level rise it shows strong analogy to developments known from the holocene rhine meuse delta outside of the glacial depressions near coastal deposits are only fragmentarily preserved the early glacial rhine sediment record is dominated by organic debris and peat layers marking landscape stability and low fluvial activity part of this record may have been formed under near coastal conditions significant amounts of reworked marine biomarkers in the lag deposits of early pleniglacial mis4 fluvial systems indicate that this period is characterized by extensive reworking of older mis5 near coastal sediments despite the marked early pleniglacial climatic cooling input of new sediment from the drainage basin was relatively low a feature that is related to the presence of regolith protective relic soil complexes in the basin during the early middle pleniglacial a major rhine avulsion indicates the system was in an aggrading mode and that sediment supply into the lower reaches of the rhine had strongly increased this increase in sediment supply coincided with the timing of major climate cooling that occurred from 50 to 45 ka onwards the increase in sediment supply is related to final breakup of the soil complexes in the drainage basin after 24 ka a strong input of coarse grained gravelly sediments was observed which indicates a strong increase in physical weathering processes and periglacial controlled supply of bedload sediment in the catchment a time delay between climate change 30 ka and channel belt aggradation 24 ka is explained as a result of transport path length between source and sink and or effects of higher continental runoff rates after 22 ka the late middle pleniglacial late pleniglacial and lateglacial rhine meuse record testifies for strong influence of glacio isostatic controlled differential upwarping of the study area glacio isostatic controlled forebulge upwarping and lateral valley tilting is shown to have deflected rhine meuse channel belts after 35 ka glacio isostatic upwarping is seen as the main cause for strong incision during the first phase of the late pleniglacial 30 24 ka at later stage glacio isostatic controlled incision was overruled due to high climate controlled sediment input from the catchment and probably initial glacio isostatic subsidence migration of channel belts towards the direction of the former centre of glacio isostatic uplift indicates that glacio isostacy influenced rhine meuse paleogeography until far into the lateglacial 2007 elsevier ltd all rights reserved

vegetation and climate of anatolia and adjacent regions during the last glacial period abstract reinterpretation of vegetation and climatic conditions of anatolia and neighboring regions during last glacial 30 15 cal ka bp have been done using a non quantitative biomization approach based on previously published plant functional types the results suggest that the climate was cold and humid before 25 cal ka bp and also during the period 23 19 cal ka bp except east anatolia forest vegetation was 80 90 of the land cover in the northwestern anatolia and black sea coast and 50 60 along the mediterranean coast at the same period during heinrich event 2 from 25 to 23 cal ka bp steppe vegetation dominated the anatolian region due to the sudden change to very cold and arid conditions approximately between 18 and 16 cal ka bp in the late glacial during heinrich event 1 a brief interval of cold and arid conditions resulted in weaker steppe vegetation over some part of anatolia around at 15 cal ka bp suitable climatic conditions for forest vegetation prevailed across a great part of anatolia except for eastern anatolia and western iran which are highlands

a new intracontinental transcurrent structure the central anatolian fault zone turkey abstract recent neotectonic studies including remote sensing aerial photographs geological field mapping on various scales and measured stratigraphic section substantiate the existence of a large sinistral intracontinental transcurrent structure which we call the central anatolian fault zone cafz this is an approximately 730 km long 2 km to 80 km wide ne trending active sinistral strike slip fault zone that cuts across the anatolian plateau between duzyayla in the northeast and anamur county in the southwest it continues onward beneath the eastern mediterranean sea and determines the boundary of the antalya and adana basins as far as to the west of cyprus the cafz is a very young neotectonic structure it resulted from the reactivation and propagation of an older paleotectonic structure the so called ecemi s corridor in both nne and sw directions across the inner tauride suture in the plio quaternary times based on geometric discontinuities the cafz is divided into 24 segments each of them is characterized by a number of strike slip morphotectonic features reflecting recent motions the easternmost part of the anatolian platelet is being deformed internally by several dextral to sinistral intraplate strike slip faults these are the lake salt fault zone lsfz the salanda fault sf the cafz the goksu yazyurdu fault zone gyfz and the malatya ovacik fault zone mofz they take up lesser motion and are younger than boundary faults of the anatolian platelet the gyfz and mofz splay from the natf cut across the anatolian platelet and then meet to the eatf whereas other faults are confined into the anatolian platelet and seem to be independent structures however present day structural pattern of all these intraplate faults and boundary faults of the anatolian platelet indicates a regional strain pattern of nnw sse directed shortening and ene wsw directed extension and they seem to have developed to accommodate northward motion of the arabian plate since late early pliocene times

late cenozoic uplift of the amanos mountains and incision of the middle ceyhan river gorge southern turkey ar ar dating of the duzici basalt using the ar ar technique we have obtained the first numerical dates for the pleistocene volcanism along the valley of the river ceyhan in the duzici area of southern turkey in the western foothills of the amanos mountains our six dates indicate a single abrupt episode of volcanism at 270 ka we have identified a staircase of 7 fluvial terraces at altitudes of up to 230 m above the present level of the ceyhan using the disposition of the basalt as an age constraint we assign these terraces to cold climate stages between marine oxygen isotope stages 16 and 2 indicating rates of fluvial incision equated to surface uplift that increase upstream through the western foothills of this mountain range at between 0 25 and 0 4 mm a 1 extrapolation of these uplift rates into the axis of the range suggests that the entire 2300 m of present day relief has developed since the mid pliocene a view that we confirm using numerical modelling since 3 7 ma the amanos mountains have formed a transpressive stepover along the northern part of the dead sea fault zone where crustal shortening is required by the geometry using a physics based technique we have modelled the overall isostatic response to the combination of processes occurring including crustal thickening caused by the shortening erosion caused by orographic precipitation and the resulting outward flow of mobile lower crustal material in order to predict the resulting history of surface uplift this modelling suggests that the effective viscosity of the lower crust in this region is in the range 1 2 1019 pa s consistent with a moho temperature of 590 10 c the latter value being in agreement with heat flow data this modelling shows that the nature of the active crustal deformation is now understood to first order at least in this key locality within the boundary zone between the african and arabian plates the structure and geomorphology of which have been fundamentally misunderstood in the past

pliocene and quaternary regional uplift in western turkey the gediz river terrace staircase and the volcanism at kula abstract along the upper reaches of the gediz river in western turkey in the eastern part of the aegean extensional province the land surface has uplifted by 400 m since the middle pliocene this uplift is revealed by progressive gorge incision and its rate can be established because river terraces are capped by basalt flows that have been k ar and ar ar dated at present the local uplift rate is 0 2 mm a 1 uplift at this rate began around the start of the middle pleistocene following a span of time when the uplift was much slower this was itself preceded by an earlier uplift phase apparently in the late late pliocene and early early pleistocene when the uplift rate was comparable to the present the resulting regional uplift history resembles what is observed in other regions and is analogously interpreted as the isostatic response to changing rates of surface processes linked to global environmental change we suggest that this present phase of surface uplift amounting so far to 150 m is being caused by the nonsteady state thermal and isostatic response of the crust to erosion following an increase in erosion rates in the late early pleistocene most likely as a result of the first large northern hemisphere glaciation during oxygen isotope stage 22 at 870 ka we suggest that the earlier uplift phase responsible for the initial 250 m of uplift resulted from a similar increase in erosion rates caused by the deterioration in local climate at 3 1 ma this uplift thus has no direct relationship to the crustal extension occurring in western turkey the rate and sense of which are thought not to have changed significantly on this time scale our results thus suggest that the present often deeply incised landscape of western turkey has largely developed from the middle pleistocene onwards for reasons not directly related to the active normal faulting that is also occurring the local isostatic consequences of this active faulting are instead superimposed onto this background of regional surface uplift modelling of this surface uplift indicates that the effective viscosity of the lower continental crust beneath this part of turkey is of the order of 1019 pa s similar to a recent estimate for beneath central greece the lower uplift rates observed in western turkey compared with central greece result from the longer typical distances of fluvial sediment transport which cause weaker coupling by lower crustal flow between offshore depocentres and eroding onshore regions that provide the sediment source

chemical controls on fault behavior weakening of serpentinite sheared against quartz bearing rocks and its significance for fault creep in the san andreas system 1 the serpentinized ultramafic rocks found in many plate tectonic settings commonly are juxtaposed against crustal rocks along faults and the chemical contrast between the rock types potentially could influence the mechanical behavior of such faults to investigate this possibility we conducted triaxial experiments under hydrothermal conditions 200 350 c shearing serpentinite gouge between forcing blocks of granite or quartzite in an ultramafic chemical environment the coefficient of friction of lizardite and antigorite serpentinite is 0 5 0 6 and increases with increasing temperature over the tested range however when either lizardite or antigorite serpentinite is sheared against granite or quartzite strength is reduced to 0 3 with the greatest strength reductions at the highest temperatures temperature weakening and slowest shearing rates velocity strengthening the weakening is attributed to a solution transfer process that is promoted by the enhanced solubility of serpentine in pore fluids whose chemistry has been modified by interaction with the quartzose wall rocks the operation of this process will promote aseismic slip creep along serpentinite bearing crustal faults at otherwise seismogenic depths during short term experiments serpentine minerals reprecipitate in low stress areas whereas in longer experiments new mg rich phyllosilicates crystallize in response to metasomatic exchanges across the serpentinite crustal rock contact long term shear of serpentinite against crustal rocks will cause the metasomatic mineral assemblages which may include extremely weak minerals such as saponite or talc to play an increasingly important role in the mechanical behavior of the fault our results may explain the distribution of creep on faults in the san andreas system

evaluation of the relative tectonic activity in the eastern lake van basin east turkey abstract the eastern part of the lake van basin van region turkey is controlled by reverse faults such as the gurpinar everek and alakoy faults these represent the major tectonic structures within the van region and have caused many devastating earthquakes based on quantitative analyses the quaternary activity and topographic relief control of each of these faults was investigated the gurpinar everek and alakoy faults are restricted to the southern slopes of the guzelsu everek and karasu basins respectively analyses of the mountain front sinuosity smf and valley floor width to height ratio vf suggest high activity along the gurpinar fault the everek fault and the western part of the alakoy fault furthermore based on the integration between smf and vf the estimated uplift rates were observed to increase from north to south the gurpinar and everek hanging wall blocks are characterized by uplift rates of 0 5 mm yr 1 whereas the alakoy fault exhibited a rate of 0 05 to 0 5 mm yr 1 these faults produce knickpoints or knickzones complex basin hypsometric curves and high values of the stream length gradient index based on these geomorphic analyses it was established that the tectonic activity of both the gurpinar and everek faults is greater than that of the alakoy fault

fluvial response to precipitation variations since 36 ka in the hunshandake sandy land in north china abstract the hunshandake sandy land which is highly sensitive to climate change is located in north china along the margins of the area influenced by the east asian monsoon the upper reach of the xilamulun river which drains the hunshandake sandy land provides an opportunity to test the response of a river landform within a sandy region to climate change we investigated terraces at 4 sites along a 38 km long stretch and performed osl dating on 26 terraces the dating results revealed 23 terraces with unsaturated ages ranging from 0 3 ka to 36 2 ka the observed relationship between the terrace heights and ages is abnormal i e the terrace age does not increase with the terrace height in this case aeolian and fluvial interactions were analyzed and a precipitation dominated terrace formation model was developed higher terraces formed when the riverbed aggraded due to decreased sediment discharge and increased aeolian sand input during a period of reduced precipitation in contrast lower terraces developed when the riverbed eroded during a period of enhanced precipitation we conclude that the terraces along this hunshandake sandy land river respond to precipitation changes even in the absence of background uplift

response of the selle river to climatic modifications during the lateglacial and early holocene somme basin northern france abstract research on lateglacial sequences from the selle valley leads to an overview of its evolution in relation to climatic variations between the end of the weichselian upper pleniglacial and the beginning of the holocene the first major modification of the fluvial morphology is dated at the upper pleniglacial lateglacial transition 13 000 14 c yr bp at that time the response to climatic improvement and environmental modifications is marked by downcutting and evolution from a braided river to a transitional river pattern bolling infilling in the newly created channels after a short cold phase recorded in a thin calcareous bed at the top of the bolling peat attributed to the older dryas dr ii the allerod is characterized by the deposition of organic overbank silts within a large single channel meandering system in lower slope environments this period is also marked by slow rates of colluvial accumulation and by the development of upbuilding soils allerod soil on the other hand the end of the lateglacial is characterised by the infilling of the whole valley by fine calcareous overbank silts during the younger dryas cold phase overflow of a large single channel and lateral input of chalk mud a second major downcutting phase occurs at the beginning of the holocene at around 10 000 bp in parallel with another rapid climatic improvement and the renewed spread of vegetation from a general point of view the evolution of fluvial environments in the selle valley is comparable with many other river valleys in nw europe showing that fluvial systems react very quickly to climatic variations of short duration 1000 to 100 years finally in the upper selle river incision events occur clearly before the main modifications of the vegetal cover they are most likely linked to a rapid shift in the balance between water discharge and sediment supply caused by climate modifications shift to more temperate and oceanic conditions and the resulting environmental changes cessation in aeolian sedimentation strong reduction of slope processes permafrost disappearance and soil development

the fluvial cycle at cold warm cold transitions in lowland regions a refinement of theory abstract a previously established non linear theory of river cyclicity as a response to climate change states that short phases of fluvial instability occur both at the transition from relatively warm temperate to cold periglacial and from relatively cold to warm periods such instability typically starts with vertical erosion successively followed by sedimentary fill of the erosive scar in spite of frequent confirmation of this theory by geomorphological reconstructions a few problems arise first there are fewer incision phases than climatic transitions secondly remnants of erosion at cold warm transitions are scarce in contrast to obvious erosion relics at warm cold transitions furthermore it appears that the incision style is strikingly different at both kinds of climatic transitions similarly the long stable phases are also expressed in terms of different floodplain development in cold and warm periods these arguments require a modification of the general non linear theory at the transition from relatively temperate to colder conditions rivers transformed gradually from a regular low energy single channel course to a periodically high energy multi channel type the latter braided type is characterized by intense lateral movement rather than by deep vertical erosion this results in a well expressed morphology of wide extensive floodplains and terraces in contrast the linear and constrained meandering channels incise with small width depth ratio and build floodplains of limited lateral extent consequences are twofold 1 the spatial limitation of the deeply incised meandering valleys at the beginning of warm periods counts against their recognition 2 relatively strong lateral migration of the braided rivers removes most traces of previous meandering systems which contrasts with the limited lateral activity of confined meandering channels it means that in a warm cold warm alternation generally only one phase of vertical erosion is preserved the one that is caused by the high energy braided river at the start of the cold period

tectonic and climatic controls on quaternary fluvial processes and river terrace formation in a mediterranean setting the goksu river southern turkey climate and tectonics effect the fluvial evolution of the mediterranean mut basin the basin contains a river terrace staircase of 16 levels t16 t1 ranging from 365 to 10a m above the current goksu river in its middle and lower sections these river terraces records tectonic uplift in the mut basin optically stimulated luminescence osl dating of the fluvial sediments of the youngest terrace t16 provides a chronology for the assessment of the important impacts of climatic changes the ages from the youngest river terrace deposits in t16 may be subdivided into two intervals 1 239 194 7 ka during the later part of marine oxygen isotope stage mis 7 implying that the aggradation of t16 started in the final phase of this warm period and 2 187 9 171 ka during much of mis 6 thus it appears that the goksu river continued depositing sediment from an interglacial into a glacial time the differences in climate driven fluvial evolution between this mediterranean fluvial system and the classical well studied temperate periglacial river systems in europe may be the result of different vegetation cover and greater thaw of more intense snowfalls 2018 university of washington published by cambridge university press

the dune systems of the konya plain turkey their relation to environmental changes in central anatolia during the late pleistocene and holocene abstract several sand flats located on the northern shores of the late pleistocene palaeolake of the konya plain inner anatolia turkey are related to changes in lake levels in this paper the two main dune systems are mapped according to their geomorphological sedimentological and dynamic characteristics and their significance is discussed with regard to the environmental changes since the late pleistocene both at time of the former lake and during the drier periods of the holocene cross sections show the relationship of the dunes to the topography of the basement analyses of the sand fraction show distinct characteristics in size distribution quartz and shell contents wind erosion effects on the quartz grains and petrographic composition interpretation of the results coupled with information provided by the geomorphology of the dune systems studied in the field and from aerial photographs and satellite images highlights the importance and variations in time of local factors such as prevailing winds sand sources changes in lake levels and vegetation a chronology of the main sand fields is proposed based on the evidence of three main droughts during the upper pleistocene the older one much eroded maximum height 3 m covers a limestone surface at 50 m above the bottom of the dried lake an optical scanning luminescence osl date shows a last period of accumulation at 14 328 3220 years the younger one maximum height 12 m has moved over the emerged late pleistocene lacustrine marls an osl date gives an age of 5674 988 years for the last accumulation period evidence of very recent activation of this younger dune system is apparent as a result of overgrazing and excessive land reclamation a third period of dominant wind action and dune construction is responsible for the installation of a younger and thin dune field over the mid holocene lacustrine deposits of the karapinar lake the success of the stabilization programme of the dunes over the last 30 years shows that the last period of dune movement is not related to climate change but to overpressure on the land due to the needs and activities of an increasing population

a new regime of slab mantle coupling at the plate interface and its possible implications for the distribution of volcanoes abstract we investigate the effects of a thin low viscosity layer just above the subducting slab on 3d thermal and flow structure in the mantle wedge by taking northeast japan as an example the low viscosity layer assumed here is needed to explain the observed low surface heat flow and low seismic attenuation in the forearc by decoupling the mantle from the subducting slab we find that when the viscosity in the low viscosity layer is sufficiently low along arc component of the flow arises inside the layer and produces along arc temperature variation it can also be considered as the along arc changes in the degree of slab mantle coupling at the plate interface the onset time and the characteristic wavelength of the 3d flow depend on the viscosity and the extent of the low viscosity layer in order to explain the observed spatial and temporal changes in the distribution of quaternary volcanoes in northeast japan the viscosity and the thickness of the low viscosity layer need to be 5 10 18 pa s and 6 km respectively the model proposed here is based on an assumption which is simpler and better constrained by observations compared to previous models therefore it could be an alternative explanation of the distribution of volcanoes in northeast japan

quaternary uplift of the northern margin of the central anatolian plateau new osl dates of fluvial and delta terrace deposits of the kizilirmak river black sea coast turkey abstract we analysed the interplay between coastal uplift sea level change in the black sea and incision of the kizilirmak river in northern turkey these processes have created multiple co genetic fluvial and marine terrace sequences that serve as excellent strain markers to assess the ongoing evolution of the pontide orogenic wedge and the growth of the northern margin of the central anatolian plateau we used high resolution topographic data osl ages and published information on past sea levels to analyse the spatiotemporal evolution of these terraces we derived a regional uplift model for the northward advancing orogenic wedge that supports the notion of laterally variable uplift rates along the flanks of the pontides the best fit uplift model defines a constant long term uplift rate of 0 28 0 07 m ka for the last 545 ka this model explains the evolution of the terrace sequence in light of active tectonic processes and superposed cycles of climate controlled sea level change our new data reveal regional uplift characteristics that are comparable to the inner sectors of the central pontides accordingly the rate of uplift diminishes with increasing distance from the main strand of the restraining bend of the north anatolian fault zone nafz this spatial relationship between the regional impact of the restraining bend of the nafz and uplift of the pontide wedge thus suggests a strong link between the activity of the nafz deformation and uplift in the pontide orogenic wedge and the sustained lateral growth of the central anatolian plateau flank

linking slab break off hellenic trench retreat and uplift of the central and eastern anatolian plateaus abstract the central and eastern anatolian plateaus are integral parts of the world s third largest orogenic plateau in the past decade geophysical surveys have provided insights into the crust lithosphere and mantle beneath eastern anatolia these observations are now accompanied by recent surveys in central anatolia and new data constraining the timing and magnitude of uplift along its northern and southern margins together with predictions from geodynamic models on the effects of various processes on surface deformation and uplift the observations can be integrated to identify probable mechanisms of anatolian plateau growth a changeover from shortening to extension along the southern margin of central anatolia that is coeval with the start of uplift can be most easily associated with oceanic slab break off and tearing this interpretation is supported by tomography deep seismicity or lack thereof and gravity data based on the timing of uplift geophysical and geochemical observations and model predictions slab break off likely occurred first beneath eastern anatolia in middle to late miocene time and propagated westward toward cyprus by the latest miocene alternatively the break off near cyprus could have occurred in late pliocene to early pleistocene time in association with collision of the eratosthenes seamount continental fragment with the subduction zone uplift at the northern margin of central anatolia appears to result from crustal shortening starting in the late miocene or early pliocene which has been linked to the broad restraining bend of the north anatolian fault the uplift history of the interior of central anatolia since the late miocene is unclear although shortening there appears to have ended by the late miocene followed by ne sw extension this change in the deformation style broadly coincides with faster retreat of the hellenic trench as well as uplift of the northern and southern margins of central anatolia these different events throughout the plateau may be linked as faster retreat of the hellenic trench has been predicted to occur after slab break off which could have induced extension of central anatolia and helped to form the north anatolian fault through accelerated westward movement of anatolia relative to eurasia correlative geochronologic evidence that we summarize here supports the hypothesis that the geodynamic activity throughout the aegean anatolian domain starting in latest miocene to early pliocene time defines a series of events that may all be linked to slab break off

from pleniglacial to holocene a 14c chronostratigraphy of environmental changes in the konya plain turkey abstract in the endoreic semi arid konya basin on the central anatolian plateaux long term hydrological evolution has left various landforms and lacustrine deposits reflecting the regional climatic evolution as well as human influence on the local environments this paper presents results from a cooperative programme grouping several institutes from turkey and france on lacustrine marshy and aeolian sediment sequences of upper pleistocene and holocene age the detailed study of environmental evolution is based on the reconstruction as well as on the characterization of the extension and contraction phases of wetlands occupying the lowest parts of the konya plain a soil and a marsh layer are 14c dated ca 28 000 25 000 yr bp three phases of pleniglacial from ca 22 000 to 17 000 yr bp high lake levels are distinguished complementary osl dates on aeolian dunes confirm the occurrence of two drought periods the first occurs around the start of the late glacial the second after the mid holocene climatic optimum the latter being in phase with a similar drought in other eastern mediterranean regions after 17 000 yr bp no lacustrine phase reached as high a level as the pleniglacial lake during the late glacial a shallow freshwater lacustrine phase is identified from 12 500 to 11 000 yr bp the late glacial to holocene transition corresponds to a general absence of deposits and dateable material thus suggesting a period of drought to which no aeolian features have so far been related the holocene environmental evolution shows a period of marsh and shallow lake extansion from 6000 to 5500 yr bp this wetter period is interrupted by the second drought ca 5500 yrs bp as indicated by aeolian dune activity during the late holocene a renewal of marshes as well as soil development on slopes can be interpreted either as climatic changes or as impacts of human use of water and soil resources during prehistoric and historic times

tectonic implications of fluvial incision and pediment deformation at the northern margin of the central anatolian plateau based on multiple cosmogenic nuclides 1 we document quaternary fluvial incision driven by fault controlled surface deformation in the inverted intermontane gok rmak basin in the central pontide mountains along the northern margin of the central anatolian plateau in situ produced 10be 21ne and 36cl concentrations from gravel covered fluvial terraces and pediment surfaces along the trunk stream of the basin the gok rmak river yield model exposure ages ranging from 7 1 ka to 346 45 ka and average fluvial incision rates over the past 350 ka of 0 28 0 01 mm a 1 similarities between river incision rates and coastal uplift rates at the black sea coast suggest that regional uplift is responsible for the river incision model exposure ages of deformed pediment surfaces along tributaries of the trunk stream range from 60 5 ka to 110 10 ka demonstrating that the thrust faults responsible for pediment deformation were active after those times and were likely active earlier as well as explaining the topographic relief of the region together our data demonstrate cumulative incision that is linked to active internal shortening and uplift of 0 3 mm a 1 in the central pontide orogenic wedge which may ultimately contribute to the lateral growth of the northern anatolian plateau

fairy chimney erosion rates on cappadocia ignimbrites turkey insights from cosmogenic nuclides abstract cappadocia in the central anatolian plateau of turkey is famous for its unique landscape and unusual rock formations the development of this landscape dates back to late miocene epoch c 10 million years when volcanoes spread pyroclastic deposits over an area of about 20 000 km 2 the volcanism continued for several millions of years and laid down thick and colorful ignimbrite layers the evolution of the cappadocian landscape starts with nearly horizontal plateaus which are then dissected usually along cooling fractures to form mushroom like structures hoodoos locally known as fairy chimneys different layers of ignimbrites have different resistance to erosion softer layers necks are easier to erode compared to the harder ignimbrites caps when the chimneys are isolated the caps play an important role in slowing further erosion of softer layers when the caps finally drop or completely erode away the soft necks of the chimneys are quickly destroyed here for the first time we have determined the bedrock erosion rates at the three evolution stages of fairy chimneys using the cosmogenic chlorine 36 36 cl the pre chimney plateaus stage the chimney stage and the post chimney stage the data show that the plateaus erode at a very low rate between 0 58 0 02 cm ky and 0 93 0 05 cm ky when dissection of a plateau starts the erosion rate increases to about 4 5 0 6 cm ky the caps of chimneys have erosion rates between 3 21 0 36 cm ky and 3 39 0 36 cm ky once the chimneys disappear erosion rates increase significantly to 28 0 9 9 cm ky

multi proxy records of quaternary fluvio lacustrine sediments around lakes eymir and mogan ankara central anatolia turkey this paper presents the mineralogical geochemical palynological and stable isotopic compositions of the late pleistocene holocene fluvio lacustrine sediments around lakes eymir and mogan ankara central anatolia it is based on the interpretation of the multi proxy records in conjunction with the geochronological data in eight different sections the comparison between the increase decrease in the abundances of carbonates and total clay assemblages is correlated with the changing abundance of coniferous forests and herbaceous plants mainly asteraceae and chenopodiaceae 13c and 18o values and molecular weathering ratios of the sediments revealing the hydrolysis evaporation and leaching together with chemical index of alteration cia provide insight into the climatic changes in the study area between 11 899 and 1428 cal year bp relatively higher total clay amount 18o of around 8 and higher cia 40 with higher hydrolysis suggest humid conditions during 11 899 6448 cal year bp between 6448 and 5763 cal year bp sediments show oscillations between high and relatively low values of the proxy data implying intercalation of dry and wet seasons the last period recorded between 5763 and 1428 cal year bp is realized with high calcite precipitation low total clay and low cia and relatively higher salinization which directly characterize aridity

climatically controlled terraces in uplifting mountain areas abstract terraces in tectonically active mountains and uplands record both tectonic uplift and rhythmic climatic variations the author discusses the question of how to distinguish the role of both tectonic and climatic factors in central europe with quaternary uplift of the order of 50 100 m climatically controlled terraces are well developed cold stage aggradation is recognised through the interfingering of periglacial alluvial slope and loess deposits erosional activity prevailed in transitional periods then follows a discussion of difficulties connected with the construction of timing and rate of tectonic uplift based on the depth of incision in the bedrock and on facies differentiation the examination of changes in longitudinal profiles of river valleys indicates that unrejuvenated upper valley courses cannot be used for the reconstruction of tectonic uplift finally the author presents several types of adaptation of tectonically determined downcutting and aggradation to quaternary climatic cyclicity

climate controlled river terrace formation in the kizilirmak valley cappadocia section turkey inferred from ar ar dating of quaternary basalts and terraces stratigraphy abstract this study was carried out on the cappadocia section of the kizilirmak river valley the longest river completely within the borders of turkey 1355 km a staircase of fifteen terraces found in the valley is maintained against erosion at elevations up to 160 m above the current river level the gulsehir karaburna quatenary basalts four basalt flows which cap four terraces were numerically dated for the first time using the ar ar technique the evren ridge basalt 1 160 m above the river level and capping terrace 1 was dated to 1989 4 38 9 ka the karaburna basalt plateau 2 is 128 m above the river level and caps terrace 4 and was dated to 1228 2 46 4 ka the tuzkoy basalt plateau 3 29 m above the river level and capping terrace 12 was dated to 403 8 9 8 ka and the karniyarik hill basalts 4 at 4 5 m above the river level and capping terrace 15 were dated to 96 0 13 0 ka these basalt ages provide minimum ages for the underlying fluvial deposits on the one hand these data show that kizilirmak river incised its valley by 160 m during the last 2 ma of its evolution on the other hand by using terrace sequences and basalt ages the time averaged incision rate of the river during the last 2 ma was determined as approximately 0 08 mm a 1 but important variations within that time span are also apparent the highest incision rate during this period was determined to be 0 12 mm a 1 between the late early and mid middle pleistocene from the numerical chronology terrace stratigraphy and paleosol records it is suggested that the main incision phases of the kizilirmak river led to terrace formation during the cold periods and the deposition phases occurred during the warm periods including cold warm transitions as a result of assigning terraces to marine oxygen isotope stages it was inferred that nearly all terrace levels had formed during the eccentricity driven climate cycles in association with high uplift rates which were interpreted as being complete in the valley

climatically controlled river terrace staircases a worldwide quaternary phenomenon a comparison of fluvial terrace sequences from around the world based on data collected as part of international geoscience programme igcp project no 449 has revealed significant patterns river terraces provide important records of uplift which is essential for their formation and of landscape evolution their cyclic formation however almost invariably seems to have been a response to climatic fluctuation sequences in the european core area of igcp 449 which has the longest and most extensive research history have been used as templates for worldwide comparison there is evidence for a global acceleration of uplift at the time of and perhaps in response to the mid pleistocene revolution when climatic fluctuation switched to 100 kyr milankovitch cycles terraces formed prior to this generally consist of wide aggradational sheets that probably each represent formation over several 41 kyr cycles subsequently river valleys became more steeply entrenched and terraces formed in response to the stronger 100 kyr climatic forcing in many cases at approximately one per cycle this paper uses the new data resource to explore differences between records in different climate zones between sequences with variable numbers of middle late pleistocene terraces and between systems in which the all important incision event has occurred in different parts of climatic cycles key records discussed include european examples from the rhine thames somme dniester dnieper don volga and aguas from asia the gediz turkey and orontes syria from north america the south platte and colorado from south africa the vaal and sundays from australia the shoalhaven and from south america the amazon paraguay and tributaries of the colorado and negro

uplift driven valley incision and climate controlled river terrace development in the thames valley uk abstract the sequence of terraces of the river thames in southeast england has previously been shown to span the period from the earliest pleistocene to the present this terrace sequence contains biostratigraphical and sedimentary evidence that testifies to the high amplitude climatic changes of the quaternary large scale fluvial incision resulting in basin wide terrace formation appears to have been concentrated at the warming limbs of the major climatic glacial interglacial cycles when sediment supply was greatly reduced this incision and subsequent valley floor widening created the accommodation space for the later aggradation of the terrace sediments during the following warm cold transitions and during the cold stages when high sediment supply conditions prevailed although the timing of terrace aggradation may be controlled by climate change the progressive valley incision recorded by terrace staircases cannot easily be explained in terms of quaternary climatic change alone and recently developed models suggest that long term incision by the thames has been driven by uplift this paper presents an overview of the available terrace data and tabulates incision amounts and rates between key stratigraphic horizons superimposed upon these broad changes revealed by the complex internal sedimentary architecture of many terrace sediments are the geomorphological system responses to both higher frequency climate driven changes and more localized intrinsic fluvial system adjustments

mio pliocene basin development in the eastern part of the cappadocian volcanic province central anatolia turkey and its implications for regional tectonics the cappadocian volcanic province cvp comprises predominantly of a thick succession of volcanogenic rocks and interbedded siliciclastic sediments of middle miocene to recent age in central anatolia turkey the conditions of basin development in the eastern part of the cvp have been elucidated by using sedimentological and geomorphological approaches the prevailing tectonic regime its extent and causes are also discussed sedimentological analysis supported by geomorphological observations revealed a major ne trending probably normal border fault and its several synthetics this tectonic element constitutes the se margin of the basin and divided the cvp from the tauride range during middle miocene to pliocene the basin fill in the study area comprises gravelly alluvial fans near the border fault while fluvial clastics and lacustrine carbonates dominate towards the centre some pyroclastic rocks and lava flows are also made part of the fill the southeastern basin margin is characterized morphologically by a number of uplifted basement blocks probably associated with synthetic faults and some deeply incised canyons in the footwall these canyons were subsequently filled with a mid pliocene ignimbrite sheet and represent the sediment supply conduits to the basin the cessation of filling in the basin was determined by strike slip faults that uplifted and detached the basin about 2 6 ma this date also marks the onset of the neotectonic period in the region the overall extensional tectonic regime inferred for the eastern cvp appears coeval with events recognised in the southern basins i e adana and mut basins and the eastern mediterranean some physical connections between these basins also have been demonstrated it is suggested that the cvp and the southern basins were all created during a phase of extension resulting from continued northward subduction of the african plate beneath the eurasia during the late cenozoic

quaternary uplift rates of the central anatolian plateau turkey insights from cosmogenic isochron burial nuclide dating of the kizilirmak river terraces the central anatolian plateau cap in turkey is a relatively small plateau 300 400 km with moderate average elevations of 1 km situated between the pontide and tauride orogenic mountain belts kizilirmak which is the longest river 1355 km within the borders of turkey flows within the cap and slowly incises into lacustrine and volcaniclastic units before finally reaching the black sea we dated the cappadocia section of the kizilirmak terraces in the cap by using cosmogenic burial and isochron burial dating methods with 10be and 26al as their absolute dating can provide insight into long term incision rates uplift and climatic changes terraces at 13 20 75 and 100 m above the current river indicate an average incision rate of 0 051 0 01 mm yr 51 1 m ma since 1 9 ma using the base of a basalt fill above the modern course of the kizilirmak we also calculated 0 05 0 06 mm yr mean incision and hence rock uplift rate for the last 2 ma although this rate might be underestimated due to normal faulting along the valley sides it perfectly matches our results obtained from the kizilirmak terraces although up to 5 10 times slower the quaternary uplift of the cap is closely related to the uplift of the northern and southern plateau margins respectively

an obliquity controlled early pleistocene river terrace record from western turkey investigation of the pleistocene sequence of the gediz river western turkey has revealed a record of early pleistocene river terraces eleven terraces spanning the interval from 1 67 to 1 245 million years ago mis 59 37 are preserved beneath basaltic lava flows the high number of terraces over this short time period reflects high frequency sedimentation incision cycles preserved due to the fortuitous combination of relatively high uplift rates 0 16 mm yr 1 and progressive southwards valley migration comparison of this record with odp967 from the eastern mediterranean basin suggests a link between the production of terraces and obliquity driven 41 000 year climate cycles in the early pleistocene

north atlantic control on precipitation pattern in the eastern mediterranean black sea region during the last glacial based on proxy records from western black sea cores we provide a comprehensive study of climate change during the last glacial maximum and late glacial period in the black sea region for the first time we present a record of relative changes in precipitation for nw anatolia based on variations in the terrigenous supply expressed as detrital carbonate concentration the good correspondence between reconstructed rainfall intensity in nw anatolia and past western mediterranean sea surface temperatures ssts implies that during the glacial period the precipitation variability was controlled like today by mediterranean cyclonic disturbances periods of reduced precipitation correlate well with low ssts in the mediterranean related to heinrich events h1 and h2 stable oxygen isotopes and lithological and mineralogical data point to a significant modification in the dominant freshwater sediment source concomitant to the meltwater inflow after 16 4 cal ka bp this change implies intensification of the northern sediment source and with other records from the mediterranean region consistently suggests a reorganization of the atmospheric circulation pattern affecting the hydrology of the european continent the early deglacial northward retreat of both atmospheric and oceanic polar fronts was responsible for the warming in the mediterranean region leading simultaneously to more humid conditions in central and northern europe

glaciations and paleoclimate of mount erciyes central turkey since the last glacial maximum inferred from 36cl cosmogenic dating and glacier modeling abstract forty four boulders from moraines in two glacial valleys of mount erciyes 38 53 n 35 45 e 3917 m central turkey dated with cosmogenic chlorine 36 36cl indicate four periods of glacial activity in the past 22 ka 1 ka 1000 calendar years last glacial maximum lgm glaciers were the most extensive reaching 6 km in length and descending to an altitude of 2150 m above sea level these glaciers started retreating 21 3 0 9 ka 1 ago they readvanced and retreated by 14 6 1 2 ka ago lateglacial and again by 9 3 0 5 ka ago early holocene the latest advance took place 3 8 0 4 ka ago late holocene using glacier modeling together with paleoclimate proxy data from the region we reconstructed the paleoclimate at these four discrete times the results show that lgm climate was 8 11 c colder than today and moisture levels were somewhat similar to modern values with a range between 20 more and 25 less than today the analysis of lateglacial advance suggests that the climate was colder by 4 5 6 4 c based on up to 1 5 times wetter conditions the early holocene was 2 1 4 9 c colder and up to twice as wet as today while the late holocene was 2 4 3 c colder and its precipitation amounts approached to similar conditions as today our paleoclimate reconstructions show a general trend of warming for the last 22 ka and an increase of moisture until early holocene and a decrease after that time the recent glacier terminates at 3450 m on the northwest side of the mountain it is a remnant from the last advance possibly during the little ice age repeated measurements of glacier length between 1902 and 2008 reveal a retreat rate of 4 2 m per year which corresponds to a warming rate of 0 9 1 2 c per century