geomorphic and biological indicators of paleoseismicity and holocene uplift rate at a coastal normal fault footwall western corinth gulf greece abstract the westernmost part of the gulf of corinth greece is an area of very fast extension and active normal faulting accompanied by intense coastal uplift and high seismicity this study presents geomorphic and biological evidence of holocene coastal uplift at the western extremity of the gulf where such evidence was previously unknown narrow shore platforms benches and rare notches occur mainly on holocene littoral conglomerates of uplifting small fan deltas they are perhaps the only primary paleoseismic evidence likely to provide information on earthquake recurrence on coastal faults in the specific part of the rift whereas dated marine fauna can provide constraints on the average holocene coastal uplift rate the types of geomorphic and biological evidence identified are not ideal and there are limitations and pitfalls involved in their evaluation in a first approach 5 uplifted paleoshorelines may be identified at 0 4 0 7 1 0 1 3 1 4 1 7 2 0 2 3 and 2 8 3 4 m a m s l probably forming after 1728 or 2250 cal b p a most conservative estimate for the average coastal uplift rate during the late holocene is 1 6 or 1 9 mm yr minimum with different amounts of reservoir correction some of the obtained radiocarbon ages of lithophaga sp allow for much higher holocene uplift rates of the order of 3 4 mm yr which cannot be discarded but require further research that the identified paleoshoreline record corresponds to episodes of coastal uplift only cannot be demonstrated beyond all doubt yet it appears the most likely interpretation given the geological and active tectonic context and present knowledge on eustatic sea level fluctuations in the mediterranean proving that the documented uplifts were abrupt i e arguably coseismic is equally difficult but rather probable five earthquakes in the last ca 2000 yr on the coastal fault zone that is responsible for the uplift compare well with historical seismicity and the results of recent on fault paleoseismological studies at the nearby eliki fault zone exact amounts of coseismic uplift cannot be determined precisely unless the rate of non seismic uplift of northern peloponnesus at the specific part of the corinth rift is somehow constrained

holocene and quaternary uplift in the central part of the southern coast of the corinth gulf greece abstract the southern coast of the gulf of corinth greece has long been recognized as an area of rapid quaternary uplift in a normal faulting environment but the amplitude dating and significance of this uplift remain a matter of debate mainly due to the scarcity of reliable and detailed estimates of holocene and longer term uplift evidence of holocene emergence is analysed for two sites in the most uplifted area of the southern coast of the gulf of corinth at mavra litharia the uppermost holocene marine limit has been identified at 9 3 m and dated about 7100 14 c years bp near platanos where the holocene marine limit is above 12 5 m in situ infralittoral boring shells at 11 5 m have been dated about 4800 14 c years bp average uplift rates can be estimated between 2 9 and 3 5 mm year at mavra litharia and possibly even greater ca 2 1 2 7 mm year near platanos the pattern of the variation of holocene uplift along the coast seems to mimic the pattern of late quaternary terraces well constrained in the eastern pattern of the gulf corinth xylokastro area

plateau icefields as contributing areas to valley glaciers and the potential impact on reconstructed elas a case study from the lyngen alps north norway

geological controls on pleistocene glaciation and cirque form in greece limestone and ophiolite rocks are common across the eastern mediterranean and many of the highest mountains are formed in these rock types in northwest greece pleistocene glacial erosion was much more effective on limestone terrain where pronounced glacial incision and subglacial glacio karst processes produced locally complex topography this enabled pleistocene glaciers to form on a range of slope orientations in contrast to ophiolite terrains where glaciers were strongly controlled by aspect on limestone terrains the largest ice masses formed on south facing slopes whereas in neighbouring higher mountains formed in ophiolite glaciers were much more restricted and predominantly formed on north and east facing slopes

the younger dryas in the eastern mediterranean abstract the younger dryas period is traced in pollen diagrams of the eastern mediterranean by means of radiocarbon dates the biostratigraphy in terms of pollen assemblages is compared with the absolute time scale the younger dryas as a pollen assemblage zone is at best vaguely visible in those parts that at present carry steppe or other open vegetation the part that nowadays carries forest produces pollen zones including the younger dryas which resemble those of parts of europe palynological developments in parts of the eastern mediterranean differ appreciably which implies that the vegetation developed differently also this suggests that the climatic development in the various parts of the region was not the same

glacial landforms and their paleoclimatic significance in sierra de guadarrama central iberian peninsula abstract this paper investigates the glacial evolution on the east face of pico de penalara 40 51 n 3 57 w 2428 m the highest elevation of sierra de guadarrama in the center of the iberian peninsula the geomorphologic stability of glacial landforms and permanence of snow cover were examined and 18 samples were selected for dating with cosmogenic isotope 36cl from moraine formations in four well differentiated phases as well as from a pre glacial periglacial blockfield and a glacial threshold near the headwall the results show the synchrony between the last glacial maximum lgm advance and most results obtained recently by cosmogenic dating in southern europe within the mis marine isotope stage 2 stadial but earlier than the global lgm i e between 25 and 19 ka bp there was slow glacial retreat with minor re advances between 19 and 16 ka and rapid deglaciation from 16 ka this paper presents initial results still pending confirmation for the minimum age of the periglacial summit block formation around 80 ka for the existence of moraine formations older than the last advance and for the existence of glaciers during the younger dryas stadial to explain the synchrony between two moraine formations at different altitudes this paper formulates the hypothesis of the secondary moraine evidenced in currently existing glaciers similar to those which existed on penalara

late pleistocene glacial events in the central apennines italy the study of glacial evidence in the gran sasso massif of the central apennines italy has allowed the last maximum advance and the subsequent stadial phases to be dated and the mean annual temperature and quantity of precipitation in the form of snow to be assessed for a number of periods the glaciers probably reached their maximum extension campo imperatore stade ca 22 60014c yr b p and started to retreat ca 21 000 yr b p leaving behind three recessional moraines after a first interstade fornaca interstade the fontari stade appears to have taken place shortly after 16 000 yr ago ca 15 000 yr ago the glacier started retreating leaving behind four more recessional moraines an interstade venacquaro interstade preceded the mount aquila stade datable at ca 11 000 yr b p a strong correlation is evident between the glacial phases on land and the isotopic variations in cores from the tyrrhenian sea

glacial history of mt chelmos peloponnesus greece mt chelmos in the peloponnesus was glaciated by a plateau ice field during the most extensive pleistocene glaciation valley glaciers radiated out from an ice field over the central plateau of the massif the largest glaciations are likely to be middle pleistocene in age smaller valley and cirque glaciers formed later and boulders on the moraines of these glacial phases have been dated using 36cl terrestrial cosmogenic nuclide exposure dating these ages indicate a late pleistocene age with glacier advance stabilization at 40 30 ka glacier retreat at 23 21 ka and advance stabilization at 13 10 ka this indicates that the glacial maximum of the last cold stage occurred during marine isotope stage 3 several thousand years before the global last glacial maximum marine isotope stage 2 the last phase of moraine building occurred at the end of the pleistocene possibly during the younger dryas

unravelling the patterns of alluvial fan development using mineral magnetic analysis examples from the sparta basin lakonia southern greece mineral magnetic analysis of b horizons of soils developing upon the surfaces of alluvial fans was undertaken in order to i differentiate and rank discrete fan surfaces by order of formation ii establish whether fan surfaces formed simultaneously in adjacent fan systems and iii deduce probable patterns of fan development the results of the analysis indicate that the greatest concentration of ferrimagnetic and anti ferromagnetic minerals occurs within soils which have developed upon the proximal fan surfaces with a progressive reduction in magnetic minerals in soils associated with medial and distal surfaces the build up of magnetic minerals in the proximal fan soils suggests that these surfaces formed first followed by the medial and distal surfaces with the exception of the kalivia sokas fan the majority of depositional events responsible for fan surface formation occurred simultaneously suggesting that adjacent fan systems share broadly similar depositional histories although the precise timing of depositional events is uncertain it is probable that by the end of the late pleistocene small largely undissected fans comprising two to three surfaces had formed at the start of the holocene fan systems experienced significant fanhead incision a net distal extension of the fan trench coupled with a progressive basinward shift of the locus of deposition during the middle and late holocene resulted in formation of medial and distal fan surfaces changes in climate are deemed to be the major control of fanhead incision fan trenching and fan surface formation however the likely effects of long term tectonic activity and approximately five thousand years of human occupation upon fan development in the sparta basin remain unclear copyright 2000 john wiley sons ltd

timing of glaciation during the last glacial cycle evaluating the concept of a global last glacial maximum lgm abstract it has long been known that mountain glaciers and continental ice sheets around the globe reached their respective maximum extent at different times during the last glacial cycle often well before the global last glacial maximum lgm c 23 19 ka which is formally defined by peaks in global sea level and marine oxygen isotope records however there is increasing evidence from around the world that it was not only mountain glaciers which were asynchronous with the global lgm but also some regions of the large continental glaciers the barents kara ice sheet in northern eurasia together with a majority of ice masses throughout asia and australasia reached their maximum early in the last glacial cycle a few thousand years before the global lgm period the east antarctic ice sheet also reached its maximum extent several millennia before the global lgm in numerous mountainous regions at high mid and low latitudes across the world glaciers reached their maximum extent before marine isotope stage mis 2 in mis 5 4 and 3 this is in contrast to most sectors of the laurentide ice sheet the cordilleran ice sheet the se sector of the fennoscandinavian ice sheet and the alpine ice sheet in central europe which appear to have reached their maximum close to the global lgm in mis 2 the diachronous maximum extents of both mountain glaciers and continental ice sheets during the last glacial cycle means that the term and acronym last glacial maximum lgm has limited chronostratigraphical meaning when correlating glacial deposits and landforms

a multiple dating method approach applied to the sanabria lake moraine complex nw iberian peninsula sw europe new evidence in the nw region of the iberian peninsula w42 n6 w of a glacial advance coeval with the global last glacial maximum lgm of the marine isotope stage 2 has been identified through a dataset of exposure ages based on 23 10 be concentration measurements carried out on boulder samples taken from a set of latero frontal moraines results span the interval 19 2e15 4 10 be ka matching the last deglaciation period when iberia experienced the coldest and driest conditions of the last 25 ka and are consistent with lateglacial chronologies established in other mountain regions from sw europe the extent of the lgm stade identified in this work is similar to the local maximum ice extent stade recorded and dated as prior to 33 ka using radiocarbon and optically stimulated luminescence this work showcases how multiple dating approaches and detailed geomorphological mapping are required to reconstruct realistic palaeoglacier evolution models

surface exposure dating of the flims landslide graubunden switzerland abstract sixteen boulder and bedrock surfaces related to the flims landslide volume 8 12 km3 were dated with 36cl and 10be exposure ages range from 4900 250 yr to 15 440 1480 yr including corrections made due to snow cover and karst erosion ages of 11 410 590 yr and 13 340 1090 yr were obtained on bedrock surfaces outside of the landslide zone these are minima for deglaciation of segnes valley and provide constraints on possible amounts of inherited nuclides based on seven boulder ages which range from 8200 260 to 9520 990 yr a mean of 8900 700 years is calculated for the flims landslide we exclude three outliers one significantly older and two significantly younger than the others and the ages from the cassons bedrock site from the mean calculation the latter is excluded as shielding due to snow and vegetation cover is difficult to constrain there the oldest boulder on the landslide yielded an age 15440 1480 yr more than 5000 years older than any other boulder age suggesting that it included the surface of the pre slide bedrock the exposure ages are consistent with a single failure event the erratics and patches of till lying on the landslide debris must have been carried piggy back on top of the landslide rather than having been deposited by the late pleistocene vorderrhein glacier the flims rockslide is about the same age as the kofels 9800 yr and kandertal 9600 yr rockslides all three occurred during the marked transition to warmer wetter conditions during the early holocene

calibration of cosmogenic 36cl production rates from ca and k spallation in lava flows from mt etna 38 n italy and payun matru 36 s argentina abstract published cosmogenic 36cl production rates from ca and k spallation differ by almost a factor of 2 in this paper we determine production rates of 36cl from ca and k in samples of known age containing little cl ca rich plagioclases and k feldspars were separated from a total of 13 samples collected on the surfaces of four basaltic lava flows at mt etna 38 n italy and from a trachyte lava flow at payun matru volcano 36 s argentina eruption ages determined by independent methods range between 0 4 and 32 ka sample site elevations range between 500 and 2500 m corresponding scaling factors were calculated using five different published scaling models four of which consider paleo geomagnetic field variations integrated over the exposure durations the resulting five data sets were then analyzed using a bayesian statistical model that incorporates the major inherent uncertainties in a consistent way spallation production rates from ca and k considering all major uncertainties are 42 2 4 8 atoms 36cl g ca 1 a 1 and 124 9 8 1 atoms 36cl g k 1 a 1 normalized to sea level and high latitude using the scaling method of stone 2000 scaling models that account for paleo geomagnetic intensity changes yield very similar mean values at most 4 if the uncertainties in the independent ages are neglected in the bayesian model the calculated element specific production rates would be about 12 higher our results are in agreement with previous production rate estimations both for ca and k if only low cl i e 20 ppm samples are considered

diatom response to the last glacial interglacial transition in the ioannina basin northwest greece implications for mediterranean palaeoclimate reconstruction uncertainty as to the pattern of lateglacial and early holocene climate change in the western balkans and greece has persisted despite extensive investigation of the ioannina i 284 lake sediment sequence northwest greece here we present a new diatom record from i 284 for this time period after dominance by eurytopic small fragilariales the lateglacial interstadial ca 14 9 12 7 cal kyr bp is marked clearly by a relative increase in planktonic cyclotella ocellata a return to small fragilariales from ca 12 7 to 11 6 cal kyr bp approximately coincides with the younger dryas chronozone it is followed by a major transition to dominance by cyclotella spp at the pleistocene holocene boundary we interpret these shifts as a response to both lake level and productivity change induced by shifts in effective moisture and temperature demonstrating that the diatom record provides the first strong evidence for a younger dryas event in northwest greece and for both warming and wetting during the lateglacial interstadial and early holocene we also present clear evidence for an abrupt phase of catchment instability during the early holocene in this case we must await the results of further research to test whether it was driven by climatic or tectonic forcing

an early advance of glaciers on mount akdag sw turkey before the global last glacial maximum insights from cosmogenic nuclides and glacier modeling abstract for the first time in turkey we report an early advance of glaciers before the broadly defined global last glacial maximum lgm forty one moraine boulders from three glacial valleys on mount akdag 36 54 n 29 57 e 3016 m southwest coast of turkey were dated with cosmogenic 36 cl valleys on the north side of the mountain were filled with few km long glaciers that terminated at elevations of about 2000 m above sea level a s l the pre lgm glaciations reached their maximum positions 2150 m a s l by 35 1 2 5 ka ago 1 ka 1000 calendar years the glaciers readvanced during the global lgm and reached their farthest locations 2050 m a s l by around 21 7 1 2 ka ago later glaciers retreated and shortly stabilized during the lateglacial at around 15 1 0 9 ka ago using the glacier modeling and paleoclimate proxies from the eastern mediterranean we estimated that if temperatures during the lgm were 8 11 c colder than modern which is suggested by paleotemperature proxies from the region precipitation was up to two times more than that of today previous estimates on southwest coast of turkey indicate a similar precipitation value while central turkey requires drier conditions implying regional heterogeneity on lgm climates in turkey

cosmogenic 36cl production rates from ca spallation in iceland abstract cosmogenic 36 cl concentrations were measured in whole rock basalt samples from twenty one surface sites on four radiocarbon dated postglacial lava flows in iceland the new 36 cl data are derived from splits of rock from the same suite of calibration sites used to determine cosmogenic 3 he production rates in recent work and thus allow a direct co calibration of production rates for these two widely used terrestrial cosmogenic nuclides ca spallation is the dominant 36 cl production reaction in our samples hence the calibration exercise is focused on this production pathway the four calibration flows yield mean ca spallation 36 cl production rates that agree within one standard deviation the grand mean ca spallation production rate from all four calibration flows in iceland is 57 5 atoms 36 cl g ca 1 yr 1 1 normalized to sea level at high latitudes with the standard atmosphere and falls within the range of values reported in previous 36 cl calibration studies we contend that the ca spallation 36 cl production rates in iceland are 17 higher than normalized values calibrated in western u s which is equivalent in direction and magnitude to the previously reported offset in calibrated 3 he production rates between these two regions relatively high terrestrial cosmogenic nuclide production rates in iceland are interpreted to reflect the time integrated impact of persistent low atmospheric pressure associated with the icelandic low the new 36 cl production rate calibrations contribute significantly to an understanding of the production systematics of this nuclide and enable accurate 36 cl surface exposure dating in iceland

the lateglacial and holocene environmental history of the ioannina basin north west greece this study centres on palaeoenvironmental analysis of the upper part of a long core from the partially drained tectonic ioannina basin north west greece the data span the lateglacial and holocene and comprise pollen mollusc magnetic susceptibility loss on ignition and particle size analyses these augment previously published ostracod and stable isotope data from the same sediment sequence the age model for the sequence is based on 19 ams dates five of which were obtained using a novel procedure for the separation of microcharcoal from sediment the pollen data suggest that although temperate woodland expanded at the beginning of the lateglacial only limited woodland contraction occurred during the younger dryas chronozone despite strong evidence for a sharp drop in sea surface temperature in the neighbouring adriatic at this time in contrast large scale vegetational and sedimentological changes occur in concert during the holocene some of which may be ascribed to human impact comparison with other records from the ioannina basin suggests that previous more littoral pollen sequences did not constitute a wholly representative record of lateglacial and holocene vegetational change

glacial activity and catchment dynamics in northwest greece long term river behaviour and the slackwater sediment record for the last glacial to interglacial transition woodward j c hamlin r h b macklin m g hughes p d lewin j 2008 glacial activity and catchment dynamics in northwest greece long term river behaviour and the slackwater sediment record for the last glacial to interglacial transition geomorphology 101 1 2 44 67 sponsorship uk science and engineering research council woodward the school of geography at the university of leeds hamlin and the university of cambridge hughes the uk natural environment research council gr9 2916 and ip 754 0302 funded the bulk of the analyses reported here specialissue sp iss si

relict rock glaciers as indicators of mediterranean palaeoclimate during the last glacial maximum late wurmian in northwest greece relict rock glaciers have been identified and mapped in the high cirques of mount tymphi in the pindus mountains of northwest greece they are periglacial forms and represent the most recent cold stage landforms in an area that displays widespread evidence of pleistocene glaciation it is likely that these features formed during the last glacial maximum late wurmian as talus rock glaciers and beneath small cirque glaciers as debris rock glaciers comparisons with modern rock glacier climate relationships suggests mean annual temperatures of ca 8 9 c lower than present at their time of formation this temperature reconstruction is in good agreement with recent palaeoclimatic reconstructions for the northern mediterranean based on a general circulation model moreover as rock glaciers are typical of cold and relatively dry mountain regions their presence is consistent with palaeobotanical and lake level data suggesting a cold and relatively dry climate for the last glacial maximum in greece however the presence of small cirque glaciers above some rock glaciers suggests that although precipitation must have been low enough to preclude glacier extension down to lower altitudes it was not so low as to inhibit glacier formation entirely copyright 2003 john wiley sons ltd

palaeogeography and 10be exposure age chronology of middle and late pleistocene glacier systems in the northern pyrenees implications for reconstructing regional palaeoclimates abstract we present constraints on the chronology palaeogeography and palaeoclimatic implications for western europe of middle and late pleistocene glaciation in the ariege catchment north eastern pyrenees based on 37 cosmogenic 10 be exposure ages obtained from moraines and glacially scoured bedrock exposures we have dated six regional glacial stades the chronology emphasises several conclusions that are new to the region i in the pyrenees the global lgm occurred several thousands of years after the maximum ice extent of the wurmian glaciation ii almost full glacier extent occurred again during the global lgm but only in the eastern pyrenees iii valley glaciers such as in the ariege trunk valley attained lengths of 25 km during the oldest dryas stadial the cosmogenic exposure ages additionally provide the first direct evidence of 10 km scale fluctuations of ice front positions during the late pleistocene glacial cycle probably at the time of marine isotope stage 3 as well as rare insights into middle pleistocene ice margin positions compared with existing evidence of glacial palaeogeography in other catchments of the pyrenan range the data also reveal a sharp contrast in relative ice extent between the glacierized catchments of the eastern pyrenees ariege carol malniu tet where wurmian mie and lgm ice fronts reached similar positions and the rest of the range where ice fronts at the time of the mis 2 and global lgm palaeotemperature minima lagged far behind the wurmian mie terminal moraines we ascribe this non uniform behaviour among catchments to non uniform palaeoclimatic conditions along the strike of the pyrenees a range of palaeoenvironmental proxies reviewed in the literature highlight a sharp difference in sea surface temperatures between the warmer western mediterranean and the cooler bay of biscay the consequences of such an e w temperature gradient on weather patterns during the global lgm are compatible with a strengthening of mediterranean low pressure systems particularly the semi permanent balearic low generating greater precipitation over the eastern pyrenees compared to atlantic weather systems further west

the campo felice late pleistocene glaciation apennines central italy study of the glacial deposits and lacustrine sediments of campo felice apennines central italy has enabled the glacial phases of the last 40 ka to be dated more precisely and has demonstrated that the maximum glacial advance did not occur in correspondence with the last global glacial maximum and with the coldest and most arid phase suggested by the pollen but in a period dated between about 33 and 27 ka characterized by a less extreme climate furthermore a glacial expansion took place also in the period prior to 35 ka correlation with the alpine glacial variations has shown that the apennine last glacial maximum occurred before that of the southern slope of the alps copyright 2012 john wiley sons ltd

geomorphology and quaternary stratigraphy the roles of morpho litho and allostratigraphy abstract the subdivision and ordering of quaternary sediments and landforms is very often based on geomorphology quaternary landforms such as moraines river terraces palaeoshorelines and indeed any other landform can be arranged and ordered in time based on their relative position in the landscape morphostratigraphy is the subdivision of sedimentary units primarily on the basis of surface form whilst surface form is often used as a criterion for separating sedimentary units morphostratigraphy also usually incorporates lithological criteria to aid stratigraphical subdivision and morpho and lithostratigraphy are often interlinked in quaternary science however another approach allostratigraphy has increasingly been applied to subdivide and order quaternary sediment landforms allostratigraphy uses discontinuities to subdivide sedimentary successions allostratigraphy enables lateral variations in lithology to be included within the same stratigraphical unit furthermore it enables lithologically similar sediments stacked on top of each other to be divided into separate units based on discontinuities this paper examines the applications of morpho litho and allostratigraphy to subdivide sediment landform assemblages and critically reviews their role in quaternary stratigraphy

controls on denudation rates in tectonically stable mediterranean carbonate terrain using cosmogenic isotopes and solute load analysis we quantify chemical weathering solutional erosion and denudation rates over variable time scales in a tectonically stable moderate relief carbonate terrain soreq drainage judea hills israel located in a semihumid mediterranean climate long term 10 4 yr denudation rates were calculated from 36 cl concentrations in 51 bedrock and sediment samples bedrock samples range in elevation 340 850 m hillslope gradient 0 30 and mean annual precipitation map 500 630 mm and vary in soil cover thickness 0 75 cm mg ca ratio 0 0 1 0 mol clay mineral contents 0 6 wt and mechanical strength 41 58 schmidt hammer rebound units soil pco2 values at a single location during the course of 1 yr range between 0 4 and 9 0 mmol mol 1 average long term denudation rate of exposed bedrock samples is 21 7 mm k y 1 field observations and 36 cl measurements indicate that soil pockets undergo cycles in the rate of deepening and that over 10 5 yr time scale average denudation rates beneath soil pockets are similar to those of exposed bedrock sediment samples yield even higher denudation rates which are probably anthropogenically induced but could also indicate that the sediment source is soil pockets long term denudation rates are decoupled from hillslope gradient elevation and rock strength denudation rates show a positive correlation with present day map values exhibit a complex relation with rock mg content and show a weak correlation with clay content annual chemical weathering rates were calculated from modern day solute load measured in waters of perched springs and the regional carbonate aquifer our results indicate that on annual decadal and 10 4 yr time scales chemical weathering and denudation are controlled by carbonate dissolution while mechanical processes are far less signifi cant overlap between the distributions of hco3 concentrations measured in runoff springs and the regional aquifer water suggests that chemical weathering focuses at the bedrock surface and therefore is comparable with solutional denudation this result is in contrast to the features of ancient fl uvial and colluvial activity steep nonconcave hillslopes and stream profi les and knickzones in the streams preserved in the present landscape such features were formed in response to mid pleistocene uplift and could have been preserved due to a decrease in stream power following the formation of subsurface drainage and the lowering in abrasive clast supply that followed the stabilization of hillslopes in the drainage long term denudation rates calculated from exposed bedrock samples are higher by factor of 1 4 relative to annual contemporary chemical weathering rates increased precipitation by a similar factor averaged over the last glacial and present interglacial can explain this difference

rates of tectonic uplift in the corinth and megara basins central greece we present evidence of the rates of late quaternary tectonic uplift that have affected parts of central greece during this period of active extension and basin formation dual lines of evidence indicate upper pleistocene to holocene uplift rates of the order of 0 3 mm yr 1 for the corinth and megara basins first u series disequilibrium ages of acropora sp corals from uplifted marine sediments are used to derive minimum average rates of vertical displacement since deposition second the geometries of cyclical transgressive sequences and of erosional terraces are consistent with the radiometric evidence and the known history of late quaternary sea level fluctuations two types of uplift are distinguished on the basis of structural relationships 1 fault block rotation about a horizontal axis tilting in response to footwall uplift on the active normal fault bounding the alkyonides gulf and 2 a more regional uplift which affects the corinth basin and peloponnesos to the south the results of u series dating are discussed in the light of initial 234u 238u activity ratios derived from the coral samples which are higher than for average marine waters 1 17 1 31 compared to 1 14 these values may be related to a variable freshwater input to the structurally confined gulf of corinth or alternatively they may reflect a previously higher global 234u 238u activity ratio in marine waters or post mortem enrichment in 234u although the mechanism of the latter is not yet understood

regional synthesis of mediterranean atmospheric circulation during the last glacial maximum atmospheric circulation leaves few direct traces in the geological record making reconstructions of this crucial element of the climate system inherently difficult we produced a regional mediterranean synthesis of paleo proxy data from the sea surface to alpine altitudes this provides a detailed observational context for change in the three dimensional structure of atmospheric circulation between the last glacial maximum lgm 23 000 to 19 000 years ago and the present the synthesis reveals evidence for frequent cold polar air incursions topographically channeled into the northwestern mediterranean anomalously steep vertical temperature gradients in the central mediterranean imply local convective precipitation we find the lgm patterns to be analogous though amplified to previously reconstructed phases of enhanced meridional winter circulation during the maunder minimum the little ice age

application of a degree day model to reconstruct pleistocene glacial climates there is empirical evidence of a nonlinear relation between annual precipitation or accumulation and summer mean temperature at the equilibrium line altitude ela on glaciers around the world the degree day model gives a similar relation between accumulation and summer temperature although instead of a single universal curve there is a family of curves depending upon the annual temperature range furthermore the degree day model also gives nonlinear relations between accumulation and annual mean temperature thus estimations of accumulation can be made from both summer and annual temperatures at the ela of former reconstructed glaciers such as those in greece this is particularly useful since these climatic variables have major implications for biological proxies such as vegetation history indicated in the pollen record and for periglacial proxies such as permafrost distributions indicated in the geomorphological record the close relationship between glaciers and climate provides one of the most precise methods for reconstructing former climates and offers considerable potential for resolving our understanding of pleistocene cold stage climates

timing of glaciation in the mediterranean mountains during the last cold stage recent research in the mountains of the mediterranean has attempted to establish the timing of the maximum extent of glaciers during the last cold stage several dating methods have been utilised and new dating frameworks have emerged in key areas in several places multiple dating techniques radiocarbon optically stimulated luminescence u series applied to glacial and associ ated sediments suggest that local glacier maxima preceded the global last glacial maximum lgm ca 18 14 c ka bp 21 cal ka bp by at least several thousand years studies in spain the pyrenees the maritime alps and turkey utilising cosmogenic isotope analyses 10 be and 36 cl have yielded glacial geochronologies with maxima that correlate closely with the marine isotope record of ice volume and the global lgm in some cases the use of different geochronological techniques has led to conflicting evidence for the timing of the local last glacier maxima in the same area from a palaeoclimate perspective glacier climate reconstructions for the local last glacier maxima in the mountains of central italy northern greece and western turkey indicate that climate was wet and cold in italy and greece the local glacier maxima preceded the driest part of the last cold stage as indicated by palaeoecological records by several thousand years for western turkey however recent cosmo genic exposure ages combined with glacier modelling suggest a local last glacier maximum charac terised by cold and wet conditions coinciding with the global lgm the available evidence indicates that a dichotomy is emerging not only in our understanding of the timing of glaciation across the mediterranean but also in the palaeoclimatic interpretations derived from glacial and palaeoecolo gical records copyright 2008 john wiley sons ltd

expression of the younger dryas cold event in the carpathian mountains ukraine past glacial activity in the ukrainian carpathian mountains is characterized by cirques glacial valleys and moraine ridges at altitudes between 1350 and 1850 m a s l although the geomorphology of this area was extensively studied the deposition time of these glacial forms and specifically the moraines was never determined we surveyed and mapped the geomorphology of the pozhezhevs ka glacial valley which is part of the charnogora ridge we used surface exposure dating and developed a data base of this area using remote sensing and geographic information system to understand the timing and nature of glacial event in the eastern carpathian mountains well developed continuous lateral frontal moraines cross the valley floor at 1400 m a s l ten sandstone boulders were sampled from one of these to determine the deposition time of the moraine samples were prepared at the glasgow university cosmogenic nuclide laboratory and analyzed at the suerc ams laboratory surface exposure ages were calculated using the cronus earth online 10be exposure age calculator our exposure ages for nine samples ukr 2 to ukr 10 range from 11 0 0 4 10be ka to 14 5 0 5 10be ka one sample ukr 1 produced no current and thus no exposure age is available the mean deposition time for the moraine ranges from 12 4 0 3 to 12 9 0 3 10be ka depending on choice of surface erosion and snow cover these results provide the first direct indication using surface exposure dating of a possible glacier response in the ukrainian carpathian mountains to a cold event contemporary with the younger dryas yd together with exposure ages from other mountain ranges across europe the new data provide direct chronological evidence for a widespread expression of the yd cold event outside the main ice margin limits left by the former scandinavian ice sheet

quaternary evolution of the corinth rift and its implications for the late cenozoic evolution of the aegean summary we present geological and morphological observations at different scales to constrain rates of faulting and the distribution of deformation in the seismically active aegean region we focus first on the 130 km long corinth rift an asymmetric graben where a flight of terraces of marine origin are uplifted we show that the edges of the terraces lie in the footwall of the normal fault bounding the corinth rift and correspond to sea level highstands of laic pleistocene age using a detailed analysis of aerial and spot imagery supported by field observations we have mapped 10 terrace platforms and strandlines ranging in elevation from 10 to 400 m over distances of 2 to 20 km from the fault the elevation of the terraces inner edges was estimated at 172 sites with an error of 5m this data set contains a precise description of the uplift and flexure of 10 different palaeohorizontal lines with respect to the present sea level to date the deformation we correlate the corinth terraces with late pleistocene oxygen isotope stages of high sea level stands and with global sea level fluctuations using a thick elastic plate model consistent with our current understanding of the earthquake cycle and a boundary element technique we reproduce the geometry of the shorelines to constrain both mechanical parameters and the slip on the fault we show that the seismogenic layer behaves over the long term as if its elastic modulus were reduced by a factor of about 1000 all the terraces are fitted for fault slip increasing in proportion to terrace age and the component of regional uplift is found to be less than 0 3 mm yr 1 the best fits give a slip rate of 11 3 mm yr 1 on the main rift bounding fault over the last 350 kyr other geological and morphologic information allows us to estimate the total age of the main fault 1 ma and to examine the mechanical evolution of the corinth rift the minimum observed sediment thickness in the gulf places an extreme check on the results of the modelling and a lower bound on slip rate of 6 7 mm yr 1 40 per cent less than estimated with modelling even this slip rate is nearly 10 times higher than for comparable features in most of the aegean and elsewhere in the world at a larger scale the spacing and asymmetry of the rift systems in the aegean suggest strain localization in the upper mantle with slow extension starting 15 myr ago or earlier the more recent 1 myr rapid phase of rifting in corinth partly reactivated this earlier phase of extension the younger faulting in corinth appears to result from its present location in the inhomogeneous stress field process zone of the south westward propagating tip of the southern branch of the north anatolian fault we extend these relations to propose a mechanical model for the late cenozoic evolution of the aegean as the arabia europe collision progressed in eastern turkey it caused anatolia to move to the west and the north anatolian fault to propagate into the aegean where the early slow extension started to be modified about 5 ma ago the process of propagation dramatically increased the activity of some but not all of the earlier rifts the model we present is compatible with tectonic observations as well as with the seismicity the palaeomagnetic rotations and the displacement field now observed with gps and slr

quaternary glacial history of mount olympus greece erosional and depositional evidence on mount olympus greece and across the adjacent piedmont provides clear indication that the mountain was more extensively glaciated over a longer period of time than has been previously reported the stratigraphic record of pleistocene holocene events on mount olympus is most clearly documented on the eastern piedmont where three discrete sedimentary packages units 1 3 each capped by a distinctive soil reflect glacial and nonglacial activity in the mount olympus region a working stratigraphic framework for sediments and soils is proposed and is tentatively correlated with a dated alluvial succession south of mount olympus we suggest that the oldest sedimentary package unit 1 predates 200 ka isotope stage 8 lithologic and pedologic equivalents of the piedmont stratigraphy are found within major valleys draining mount olympus as well as within cirque basins and on the summit plateau surface these deposits can be clearly tied to three stages of cirque development on the upland and at valley heads taken together upland and piedmont glacial features and deposits indicate the following general scenario 1 earliest glaciation isotope stage 8 produced upland ice and valley glaciers that extended as piedmont lobes east north and west of mount olympus 2 nonglacial interglacial conditions isotope stage 7 were accompanied by extensive erosion and subsequent pedogenesis 3 a second glaciation isotope stage 6 involved production of upland ice and valley glaciers that did not reach the piedmont 4 interglacial interstadial conditions isotope stage 5 provided time for stream erosion and substantial pedogenesis 5 final glaciation isotope stages 4 2 was restricted to valley heads no upland ice and glaciers that extended to mid valley positions 6 nonglacial conditions isotope stage 1 were associated with additional pedogenesis and stream incision the largest cirque on the mountain megali kazania may contain depositional evidence for neoglaciation study of the neotectonic history of the mount olympus region indicates that uplift has persisted throughout the mid pleistocene and holocene at a rate of about 1 6 m k y the total uplift since deposition of unit 2 is approximately 200 m

a stratigraphical basis for the last glacial maximum lgm abstract the last glacial maximum lgm is widely used to refer to the episode when global ice volume last reached its maximum and associated sea levels were at their lowest however the boundaries of the interval are ill defined and the term and acronym have no formal stratigraphical basis this is despite a previous proposal to define it as a chronozone in the marine records on the basis of oxygen isotopes and sea levels spanning the interval 23 19 or 24 18 ka and centred on 21 ka in terrestrial records the lgm is poorly represented since many sequences show a diachronous response to global climate changes during the last glacial cycle for example glaciers and ice sheets reached their maximum extents at widely differing times in different places in fact most terrestrial records display spatial variation in response to global climate fluctuations and changes recorded on land are often diachronous asynchronous or both leading to difficulties in global correlation however variations in the global hydrological system during glacial cycles are recorded by atmospheric dust flux and this provides a signal of terrestrial changes whilst regional dust accumulation is recorded in loess deposits global dust flux is best recorded in high resolution polar ice core records providing an opportunity to define the lgm on land and establish a clear stratigraphical basis for its definition on this basis one option is to define the global lgm as an event between the top end of greenland interstadial 3 and the base onset of greenland interstadial 2 spanning the interval 27 540 23 340 ka greenland stadial 3 this corresponds closely to the peak dust concentration in both the greenland and antarctic ice cores and to records of the global sea level minima this suggests that this definition includes not just the coldest and driest part of the last glacial cycle but also the peak in global ice volume the later part of the lgm event is marked by heinrich event 2 which reflects the onset of the collapse of the laurentide at c 24 ka together with other ice sheets in the north atlantic region a longer and later span for the lgm may be desirable although defining this in chronostratigraphical terms is problematic whichever formal definition is chosen this requires the contribution of the wider quaternary community

middle pleistocene cold stage climates in the mediterranean new evidence from the glacial record abstract a major reduction in summer temperatures during a middle pleistocene glacial cycle caused the most extensive glaciation recorded in the mediterranean region glaciers in the mountains of greece formed during marine isotope stage mis 12 474 000 427 000 years bp under climatic conditions characterised by mean summer temperatures at least 11 c cooler than today and annual precipitation of 2300 mm at the equilibrium line altitude 1741 m a s l this represents the coldest mean summer temperatures recorded in greece during at least the last 430 000 years later pleistocene glaciations mis 6 and 5d 2 were characterised by warmer summer temperatures and higher annual precipitation

combined numerical and geomorphological reconstruction of the serra da estrela plateau icefield portugal abstract the paper focuses on reconstructing a plateau icefield surface from field geomorphological data and a physical based glacier model the results allow the analysis of the patterns of glacial erosion and the estimation of the palaeo equilibrium line altitudes ela the study area is the serra da estrela a plateau in central portugal rising to 2000 m asl the glaciated area during the last maximum of the serra da estrela glaciation lmgse was 66 km 2 the reconstruction of the topography of the icefield and valley glaciers in the lmgse is based on the schilling and hollin model it iterates along the valley longitudinal profile and is based on the gradient on valley shape indices and on yield basal shear stresses these variables influence ice thickness and therefore also the slope of the ice surface allowing for its reconstruction the key variable is basal yield shear stress and its value was included in the model manually starting from the points of maximum extent of the valley glaciers and following a range known to occur in contemporary conditions the input values are validated by matching the resulting ice surface to geomorphological features where these are absent a constant value of 100 kpa was used the icefield was reconstructed from a radiating set of long sections along which ice thicknesses were calculated a dem of the ice surface was constructed allowing the estimation of the hypsometric curves of the distinct glacier catchments and the calculation of the palaeo elas the results show a regional ela at 1650 m asl with spatial variations across the icefield reflecting mainly the effect of eastward snow drift the lmgse glaciers were very sensitive to minor climatic changes especially due to the large area of the plateau icefield and to the positioning of the elas close to or in the flat part of the hypsometric curve the model of the ice surface is of significant value for the analysis of the patterns of glacial erosion at the landscape level in the serra da estrela most of the glacial erosion occurred near the plateau margins and in valley heads where glacier surface slope was steeper allowing for a faster ice flow and where ice flow concentrated strong glacier erosion in the zezere valley is linked to the tectonic setting but also to the confluence of glaciers and to the overfeeding of snow from the plateau

climate at the equilibrium line of glaciers the relationships between temperature precipitation and radiation on glacier equilibrium lines are investigated using 70 glaciers for which the mass balance and meteorological observations have been carried out for sufficiently long periods it is found that the characteristic climate at glacier equilibrium lines can be described using the summer 3 months temperature in a free atmosphere annual total precipitation and the sum of global and long wave net radiation all of these are measured at or very near the equilibrium line altitudes then it is shown how the shift of the equilibriumline will occur as a result of a climatic change finally the effect of the shift of the equilibrium line on the annualmean specific mass balance is analytically derived and compared with observations the present results make it possible to identify the altitudes in climate models where glacierization should begin and to evaluate the mass balance changes as a result of possible future changes in the climate

the glacial history of the pindus mountains greece abstract geomorphological evidence for pleistocene glaciation has been mapped in the pindus mountains of northwest greece and the chronology of glaciation in this area has been established through soil profile analysis and u series dating of secondary carbonates calcite formed within glacial deposits three glacial stages are evident in the sedimentological and geomorphological records the earliest and most extensive recorded glaciation predates 350 000 yr b p and was characterized by extensive valley glaciers and ice fields a more recent glaciation occurred before the last interglacial and was characterized by glaciers that reached midvalley positions the last phase of glaciation in greece is recorded by small cirque glacier moraines and relict periglacial rock glaciers the glacial and periglacial sequence on mount tymphi has been used in conjunction with a reference parastratotype the long lacustrine sequence at ioannina to provide a chronostratigraphical framework for cold stage deposits in g

the geomorphological impact of loch lomond younger dryas stadial plateau icefields in the central lake district northwest england detailed geomorphological mapping has revealed evidence for the development of plateau icefields in the central fells of the english lake district during the loch lomond younger dryas stadial ca 12 9 11 5 ka the largest plateau icefield system which covered an area of approximately 55 km2 including outlet glaciers was centred on high raise to the west smaller plateau icefields developed on grey knotts brandreth and dale head covering areas of 7 km2 and 3 km2 respectively the geomorphological impact of these plateau icefields appears to have been minimal on the summits where the survival of blockfields and other frost weathered debris mostly peat covered implies the existence of at least patches of protective cold based ice ice moulded bedrock at some plateau edges however documents a transition to wet based erosive conditions prominent moraine systems were produced by outlet glaciers which descended into the surrounding valleys where their margins became sediment traps for supraglacial debris and inwash in some valleys ice marginal moraines record successive positions of outlet glaciers which actively back wasted towards their plateau source this interpretation differs from that of previous workers who assumed an alpine style of glaciation with reconstructed glaciers emanating from corries and valley heads it is likely that plateau icefields were more common at this time in upland britain than hitherto has been appreciated

last glacial maximum and deglaciation of sierra de gredos central iberian peninsula abstract the study area is located in the sierra de gredos a portion of the sistema central range of central spain specifically in the gredos gorge on the north side of pico almanzor 2596 masl where glacial forms are present down to an altitude of 1410 m 10 km from the headwall this paper presents cosmogenic 36 cl surface exposure dates of four closely spaced lateral moraine ridges within the area of maximum advance of the ancient glacier 8 km from the headwall and two glacially polished bedrock thresholds 3 and 5 km from the headwall the dates are overall coherent and indicate a maximum advance at 26 24 ka subsequently the glacier front stabilized around its maximum position for 3 ka with small scale fluctuations resulting in small closely spaced moraines ridges glacier recession began after 21 ka accelerating sharply by 16 ka the glacier had probably disappeared from the gredos gorge by 15 ka there are no traces of older or more recent moraines than those dated in this study these results are in agreement with the well known late pleistocene climatic evolution of the northern atlantic and with the glacial chronology of the alps and other mediterranean mountains however the gredos gorge has no geomorphic evidence of the younger dryas cold event probably because of the low altitude and southern character of these mountains

beryllium boron and aluminum magnesium chronology of calcium aluminum rich inclusions in cv chondrites we have made be b measurements in six calcium aluminum rich inclusions cais mostly type b inclusions from cv chondrites and compared them to al mg measurements all cais show 10b excesses in melilite that are correlated with be b ratios the initial 10be 9be ratio inferred from the correlation line is 6 2 times 10 4 in contrast to the be b system in melilite the al mg system in anorthite is disturbed this is probably due to b diffusion in melilite being slow compared with mg diffusion in anorthite this suggests that be b chronology may be useful for measuring time differences of high temperature melting condensation etc events in the early solar system

geomorphology and style of plateau icefield deglaciation in fjord terrains the example of troms finnmark north norway in spite of a widespread distribution the way in which plateau icefields affect the glaciation and deglaciation of adjacent terrains is not particularly well known this paper aims to identify how the deglaciation of the fjord and plateau terrain of north norway has influenced the glacial geomorphology and relative sea level history of both local and adjacent areas and so serve as a model for interpreting similar areas along the continental margins of northwest europe and elsewhere the identification of moraines and their relationships with the main shoreline of northern norway allows the margins of the oksfjordjokelen svartfjelljokelen and langfjordjokelen plateau icefields to be identified in the adjacent terrains in locations where ice margins are uncertain it is also possible to reconstruct ice limits by means of glacier models appropriately constrained by known local conditions and dates earlier glacier margins characterised in north norway by ice shelves floating in the local inlets of major fjords also can be related to known regional shorelines the distribution of high shoreline fragments augmented by radiocarbon dates helps show the extent to which inter island channels and outermost parts of fjords can become deglaciated relatively early in comparison with published maps of regional deglaciation plateau icefield centred glaciation became important sometime after 14 000 14c yr bp and was characterised by glacier readvances up to and in some locations beyond earlier moraines and raised marine features although overlooked until recently the identification of the influence of plateau icefields on local glaciation and their interaction with local and regional marine limits is of great importance in accurate palaeoenvironmental reconstruction copyright 2002 john wiley sons ltd

late pleistocene and holocene sea level change in greece and south western turkey a separation of eustatic isostatic and tectonic contributions summary sea level change during late pleistocene and holocene times is a combination of eustatic isostatic and tectonic contributions in the central mediterranean sea region of greece and western turkey the isostatic components are important due to the changing gravitational potential of the earth the readjustment of the crust upon the removal of the large ice sheets and the addition of the meltwater into the oceans including the mediterranean changes in relative sea level due to these glacio hydro isostatic adjustments have reached amplitudes of 1 mm yr 1 during the last few thousand years a model for the isostatic contribution to sea level change including the movement of shorelines due to the combined eustatic isostatic changes is developed based on earth model and ice sheet parameters estimated from sea level observations from other areas comparisons of this model with observations of sea level change permit rates of vertical movement to be estimated for late holocene time allowance for the isostatic factors makes a significant difference to these rates the plains of argolis lakonia messinia and navarine in the southern peloponnese for example appear to be tectonically stable on time scales of a few thousand years and longer consistent with the position of the last interglacial shoreline close to the present day sea level the observations here of a rising sea level are largely the consequence of the glacio hydro isostasy and not of a long term tectonic process crete as a whole is subject to tectonic uplift but at variable rates and forms part of an arcuate zone of uplift extending from rhodes and karpathos in the east to kithera in the west at rates that locally exceed 4 mm yr 1 the southern shore of the gulf of corinthos is also subject to uplift at rates approaching 1 5 mm yr 1 these isostatically corrected estimates for the past few thousand years are in agreement with longer term estimates based on the position of the last interglacial shoreline only on the perachora peninsula do the tectonic rates over these two time intervals appear to be in disagreement with the late holocene rates being much higher than the long term rates

alluvial sediment sources in a glaciated catchment the voidomatis basin northwest greece x ray diffraction xrd of the fine matrix component of four alluvial units and modern channel sediments in the voidomatis river basin of northwest greece shows that fine sediment sources have changed considerably during the late quaternary the matrix fraction of the modern channel sediments is derived predominantly from erosion of local flysch rocks and soils during the last glaciation however the fine sediment load of the voidomatis river was dominated by glacially ground finely comminuted limestone materials limestone derived fine sediment is not produced in significant amounts under modern climatic conditions by combining this xrd work with a detailed programme of clast lithologic 1 analysis we have reconstructed former bedload and fine sediment load composition the lithological properties of both the coarse 8 256 mm and fine 63 m elements of the sediment load have varied markedly during the late quaternary a simple semiquantitative assessment of fine sediment mineralogy using diffractogram peak height data has provided a valuable complement to the information gathered from more traditional clast lithological techniques together in favourable geological settings fine fraction mineralogy and clast lithological analysis can provide a valuable tool for the reconstruction of late quaternary alluvial environments

late quaternary fluvial sedimentation in the voidomatis basin epirus northwest greece abstract detailed morpho and lithostratigraphic investigations allied with radiometric dating in the voidomatis basin epirus northwest greece have identified four quaternary terraced alluvial fills that range from middle pleistocene to historic in age major periods of alluviation during the late quaternary were associated with valley glaciation ca 26 000 20 000 yr b p and subsequent deglaciation ca 20 000 15 000 yr b p in the pindus mountains during late wurmian times and more recently linked to overgrazing sometime before the 11th century ad the late quaternary alluvial stratigraphy of the voidomatis river is more complex than the older fill and younger fill model outlined previously and it is suggested that these terms should no longer form the basis for defining alluvial stratigraphic units in the mediterranean basin

the last deglaciation in the picos de europa national park cantabrian mountains northern spain a sedimentological and geochemical study of the lago enol sequence cantabrian mountains northern spain together with detailed geomorphological mapping provides a first record of glacier evolution and climate change over the last 40 ka in the picos de europa national park the enol glacier retreated from its maximum extent prior to 40 ka bp as demonstrated by the onset of proglacial lacustrine sedimentation in two glaciated depressions the comella hollow to the north before 40 ka bp and the lago enol before 38 ka bp these results support previous evidence that the maximum extent of southern european glaciers occurred earlier than in northern europe alternation of homogeneous and laminated proglacial sediments during the glacier retreat illustrate a dynamic glacial evolution during the marine isotope stage mis 3 40 26 ka bp a slight warming is detected at 26 ka ago with the change from proglacial sediments in a lake located in contact to the glacier to glaciolacustrine sedimentation in a non contact or distal lake finally the onset of organic rich sediments took place at 18 ka ago this last transition occurred in two phases similarly to the north atlantic last termination suggesting a link between north atlantic deep water formation oscillations and palaeohydrological variability in the cantabrian mountains copyright 2009 john wiley sons ltd

late pleistocene piedmont glaciations in the eastern mediterranean insights from cosmogenic 36cl dating of hummocky moraines in southern turkey abstract we report the presence of late pleistocene piedmont glaciers represented by the largest hummocky moraine field observed in the eastern mediterranean the piedmont glaciers originated from the geyikdag ice cap 40 km 2 situated between 2350 and 2650 m above sea level a s l central tauride mountains of turkey and deeply carved the north facing hillslopes before reaching the namaras valley 2000 2050 m a s l the hummocky moraines resulted from in situ deposition of stagnant glacier ice where debris cover was heterogeneously distributed on the glacier surface thirty four boulders from hummocky disintegration lateral and terminal moraines from the namaras valley and the tributary susam valley 2100 2200 m a s l were dated by cosmogenic 36 cl surface exposure dating the moraine ages indicate three phases of deglaciation during the late pleistocene the oldest deglaciation occurred in the namaras valley at 18 0 1 1 ka ka thousand years ago towards the end of the last glacial maximum lgm and is recorded entirely by hummocky moraines we speculate that hummocky moraine forming processes with cycles of relief inversion gave rise to boulder apparent ages up to a few thousand years younger in our study area therefore 18 0 1 1 ka should be regarded as a minimum age with a probable true age much closer to the local lgm values 20 ka as observed in the surrounding mountains paleo piedmont glaciers also deposited several lateral moraines that are 50 m higher than the hummocky moraines although the lateral moraines probably represent the build up and the hummocky moraines the final phase of the same local lgm pulse both lateral moraines started to retreat from the late glacial 14 0 2 7 ka and gradually disappeared by mid holocene 5 2 1 0 ka encompassing the younger dryas yd stadial in the susam valley the late glacial is represented by a terminal moraine 13 4 1 5 ka the glacier retreat was very fast as indicated by an almost instantaneous disappearance of 5 km long susam valley glacier represented by disintegration and hummocky moraines 14 0 1 3 ka alternatively in case the oldest boulder age is taken into account the susam valley glacier can be also attributed to the late lgm 17 ka to late glacial 14 ka transition near the exit of the susam valley a right lateral moraine was deposited 11 6 1 3 ka ago confirming the presence of the yd in geyikdag comparable glacial chronologies were obtained from other turkish and mediterranean mountains

dating inset terraces and offset fans along the dehshir fault iran combining cosmogenic and osl methods summary be and 36 cl cosmic ray exposure cre and optically stimulated luminescence osl dating of offset terraces have been performed to constrain the long term slip rate of the dehshir fault analysis of cosmogenic 10 be and 36 cl in 73 surface cobbles and 27 near surface amalgamscollectedfrominsetterracesdemonstratestheoccurrenceofalowdenudationrateof 1mm a 1 and of a significant and variable inheritance from exposure prior to the aggradation of these alluvial terraces the significant concentrations of cosmogenic nuclides measured in the cobbles collected within the riverbeds correspond to 72 20 ka of inheritance the mean creageofthesurfacesamplescollectedontheolderterracet3is469 88kabuttheanalysis of the distribution of 10 be concentration in the near surface samples discard ages older than 412 ka the mean cre age of the surface samples collected on terrace t2 is 175 62 ka but the 10 be depth profile discard ages older than 107 ka for each terrace there is a statistical outlier with a younger age of 49 9 3 3 and 235 5 35 4 ka on t2 and t3 respectively the late sediments aggraded before the abandonment of t2 and inset levels t1 b and t1a yielded osl ages of respectively 26 9 1 3 21 9 1 5 and 10 0 0 6 ka for a given terrace the osl ages where available provide ages that are systematically younger than the cre ages these discrepancies between the cre and osl ages exemplify the variability of the inheritance and indicate the youngest cobble on a terrace that minimizes the inheritance is the most appropriate cre age for approaching that of terrace abandonment however the upper bound on the age of abandonment of a terrace that is young with respect to the amount of inheritance is best estimated by the osl dating of the terrace material for such terraces the cre measurements are complementary of osl dating and can be used to unravel the complex historyofweatheringandtransportinthecatchmentofdesertalluvialfans thiscomprehensive set of dating is combined with morphological offsets ranging from 12 2t o 380 20 m to demonstrate the dehshir fault slips at a rate in the range 0 9 mm yr 1 1 5 mm yr 1 t he variable inheritance exemplified here may have significant implications for cre dating in arid endorheic plateaus such as tibet and altiplano

the glacial history of the dinaric alps montenegro abstract large areas of montenegro were glaciated during the pleistocene this paper presents evidence from the massifs of central montenegro including durmitor and sinjajevina moracke planine maganik prekornica and vojnik glacial deposits have been subdivided on the basis of morphostratigraphy and soil weathering and 31 u series ages from cemented tills provided a geochronological framework the largest glaciation occurred before 350 ka when a series of conjoined ice caps over the massifs of central montenegro covered a total area of nearly 1500 km 2 these formed during mis 12 and correspond with the largest skamnellian stage glaciations in greece to the south later middle pleistocene glaciations occurred during the penultimate glacial cycle correlating with the vlasian stage in greece mis 6 when ice caps covered an area of 720 km 2 over central montenegro there is also geochronological evidence of glacial deposits dating from the interval between mis 12 and mis 6 before the interglacial complex of mis 7 this glaciation appears to have been very similar in extent to that which occurred during mis 6 the last glacial cycle in central montenegro was characterised by valley and cirque glaciers covering a total area of 49 km 2 it is very likely that glaciers have been present in the mountains of central montenegro during every glacial cycle since a small glacier still survives today the smaller glaciers of the last glacial cycle are likely to have been associated with summer temperatures that were warmer than those of earlier cold stages the striking contrast in the extent and thickness of ice cover during the cold stages of the pleistocene has an important bearing on the geomorphological and biological evolution of the balkans

quaternary glacial evolution in the central cantabrian mountains northern spain abstract the glacial evolution of the cantabrian mountains is not well known previous studies have focused on the extent of the glacial maximum and the presence of younger features in several massifs recently efforts have been made to date glacial periods particularly the glacial maximum this work presents a reconstruction of the glacial evolution in the cantabrian mountains providing data on the environmental characteristics and timing of the different stages from the quaternary glacial maximum to the little ice age the study area covers 3000 km 2 between the 4 58 w and 3 34 w and includes eleven massifs of the central area of the cantabrian mountains the selected sectors have an atlantic and atlantic mediterranean transitional climate and include the highest massifs above 2600 m and low altitude glacierised massifs lower than 2000 m glacial extent and evolution have been reconstructed on the basis of detailed geomorphological and morphostratigraphic mapping the equilibrium line altitude palaeo ela has been estimated for the different stages of each tongue the ela has been assessed by the aar and modified kurowski methods and altitude methods have been considered a numerical chronological framework is proposed using 17 ams radiocarbon and one osl data obtained in lake and bog deposits from three massifs four main glacial stages have been differentiated between 38 000 bp and the little ice age they correspond to different cold environments and the number of glacial stages varies from one to four among the different massifs conclusions are analysed in the context of the quaternary glacial evolution of other iberian mountains

synchronous last glacial maximum across the anatolian peninsula uludag is a prominent mountain in northwestern turkey where glacial deposits have been documented in the kovuk valley and the glacial history has been reconstructed based on 31 cosmogenic 10 be exposure ages from glacially transported boulders and bedrock the results suggest that the kovuk glacier began advancing before 26 5 1 6 ka it reached its maximum extent at 20 3 1 3 ka followed by a re advance at 19 3 1 2 ka both during the global last glacial maximum lgm within marine isotope stage 2 the timing of the lgm glaciations in the kovuk valley is consistent with the investigated lgm glaciations in other mountains of anatolia the mediterranean and the alps based on the geomorphological ice margin reconstruction and using the accumulation ablation area ratio aar approach the equilibrium line altitude ela of the kovuk lgm glacier was c 2000 m above sea level for an estimated aar of 0 67 this indicates a c 1000 m lowering of the ela for the lgm compared with the modern ela estimate these lines of evidence are consistent with the lgm glaciers that have been documented elsewhere in the anatolian mountains

pleistocene ice caps on the coastal mountains of the adriatic sea ice caps once covered large areas of mount orjen 1894 m on the adriatic coast of montenegro bosnia herzegovina croatia the largest ice cap covered an area of c 165 km2 and reached a maximum ice thickness of c 450 m in some areas reaching down to 500 m above modern sea level u series dating of secondary carbonates within moraines indicates that the most extensive glaciation occurred during the middle pleistocene correlating with a major phase of glaciation in greece to the south during mis 12 c 480 430 ka later less extensive glaciations are also recorded in the cirques and valleys and correlate with glaciations during mis 6 190 130 ka and mis 5d 2 110 11 7 ka each phase of glaciation would have required large amounts of snow accumulation under modern precipitation values which at c 5000 mm are some of the highest in europe mean annual temperatures would need to be only c 5 6 c lower in order to form similar sized glaciers today a mean annual temperature depression of 12 13 c would still require 1000 mm of snow accumulation water equivalent to balance ablation suggesting sustained moisture supply during pleistocene cold stages such sustained precipitation supply during pleistocene cold stages is likely to have been facilitated by major temperature contrasts between the european landmass and the mediterranean sea which are likely to have sustained lee side vortices to the south of the alps in the gulf of genoa and adriatic sea forming weak moisture bearing depressions which tracked across the eastern adriatic coastal mountains large ice caps on the dinaric alps would have blocked the inland penetration of these depressions resulting in much drier conditions in the balkan interior creating favourable conditions for the deposition of thick accumulations of loess the last glaciers on orjen formed during the younger dryas 12 9 11 7 ka and confirm the influence of north atlantic ocean circulation on pleistocene climate change in this part of the mediterranean

debris covered glaciers in the sierra nevada california and their implications for snowline reconstructions abstract ice walled melt ponds on the surfaces of active valley floor rock glaciers and matthes little ice age moraines in the southern sierra nevada indicate that most of these landforms consist of glacier ice under thin ca 1 10 m but continuous covers of rock fall generated debris these debris blankets effectively insulate the underlying ice and greatly reduce rates of ablation relative to that of uncovered ice such insulation explains the observations that ice cored rock glaciers in the sierra actually debris covered glaciers are apparently less sensitive to climatic warming and commonly advance to lower altitudes than do adjacent bare ice glaciers accumulation area ratios and toe to headwall altitude ratios used to estimate equilibrium line altitudes elas of former glaciers may therefore yield incorrect results for cirque glaciers subject to abundant rockfall inadvertent lumping of deposits from former debris covered and bare ice glaciers partially explains an apparently anomalous regional ela gradient reported for the pre matthes recess peak neoglacial advance distinguishing such deposits may be important to studies that rely on paleo ela estimates moreover matthes and recess peak ela gradients along the crest evidently depend strongly on local orographic effects rather than latitudinal climatic trends indicating that simple linear projections and regional climatic interpretations of ela gradients of small glaciers may be unreliable

extensional tectonics in mt parnon peloponnesus greece peloponnesus in the south western part of the aegean is formed by a heterogeneous pile of alpine thrust sheets that was reworked by normal faulting from upper miocene to recent times upper miocene lower pliocene extension in mt parnon was accommodated by several mappable brittle detachment faults that exhibit a top to the ne ene sense of shear the hanging wall of the detachments comprises a number of highly tilted fault blocks containing abundant evidence of intense internal deformation by normal faulting and layer parallel shearing contemporaneous with faulting these fault blocks are remnants of a cohesive extensional block that slipped to the ne ene and broke up along high angle normal faults that sole into or are cut by the detachments the largest part of this block is located at the eastern edge of the metamorphic core forming the hanging wall of east parnon high angle normal fault that excised part of the aforementioned detachments the lowermost metamorphic unit of the nappe pile does not seem to be affected by the previous extensional episode upper plate reconstruction shows that various units of the nappe pile were affected by high angle normal faults that linked to detachment faults in the weaker layers since the middle upper pliocene further exhumation of the metamorphic rocks has resulted in the formation of high angle normal faults overprinting neogene extensional structures and cut the entire nappe pile this new fault system tilted the earlier extensional structures and produced a ne sw coaxial deformation of mt parnon

cosmogenic chlorine 36 from calcium spallation calcium is a major target element for cosmogenic 36cl production consequently 36cl rapidly reaches detectable levels in minerals such as calcite and calcium feldspar exposed at the earth s surface spallation of calcium isotopes typically accounts for 80 90 of 36cl production in these minerals with subsidiary contributions from negative muon capture by 40ca and thermal neutron capture by 35cl to provide a basis for surface exposure dating we have calibrated cosmogenic 36cl production in calcium feldspar from the 17 300 year old tabernacle hill basalt at an altitude of 1445 m and an effective geomagnetic latitude of 40 9 the calcium spallation rate is 152 11 atoms g ca 1 a 1 the corresponding rate at sea level and high latitude is estimated at 48 8 3 4 atoms g ca 1 a 1 the muon capture rate used to derive these values is 8 8 2 2 atoms g ca 1 a 1 at the tabernacle hill site scaled from a value of 4 8 1 2 atoms g ca 1 a 1 at sea level and high latitude the calcium spallation rate determined in this study is in excellent agreement with previous whole rock calibration measurements at tabernacle hill when these are recalculated with respect to the absolute timescale the calibration of 36c1 production from calcium underpins development of an exposure dating technique for calcite due to its high calcium content the 36cl production rate in calcite is higher than in any other common rock forming mineral measurement of 36cl in calcite with an accelerator mass spectrometric detection limit of 5 103 atoms per gram allows dating of limestone surfaces exposed for periods ranging from 102 106 years alternatively erosion rates from less than 1 to greater than 1000 m per year can be determined in the case of eroding karst surfaces though the 36cl production rate is lower in calcium feldspar than in calcite measurements on this mineral will provide a useful means of dating young basalt lavas