biostratigraphical correlation of the campanian maastrichtian boundary lagerdorf hemmoor northwestern germany dsdp sites 548a 549 and 551 eastern north atlantic with palaeobiogeographical and palaeoceanographical implications a correlation of the campanian maastrichtian boundary is attempted using foraminiferal and nannoplankton data from two areas the eastern north atlantic and northwestern germany the boreal benthic and tethyan planktonic foraminiferal zonation schemes are applied to site 548a where both foraminiferal groups occur frequently a direct comparison of both biozonations reveals that the base of the maastrichtian according to planktonic foraminifers has to be placed in the upper campanian of the boreal benthic foraminiferal biozonation which concurs with the nannoplankton results the tethyan middle and upper maastrichtian are probably equivalent to the upper maastrichtian in the boreal sense the bases of the maastrichtian substages are thus diachronous between the boreal and tethyan realms palaeotemperatures which were estimated using the oxygen isotopic composition of the goban spur chalks indicate in combination with palaeowind directions that the faunal and floral distribution pattern recorded is the result of a stable warm water outflow from the northwest european epicontinental seas through the channel area to the celtic shelf sea and goban spur this mechanism appears to have been a dominant separating factor of the boreal and tethyan bioprovinces on the western european shelf

tidal modeling of an ancient tide dominated seaway part 1 model validation and application to global early cretaceous aptian tides abstract the utility of deep time global paleotidal modeling is evaluated with a series of modeling experiments focused on the early cretaceous aptian the results from a series of paleobathymetry sensitivity experiments indicate that despite paleogeographic and paleobathymetric uncertainty appropriate use of global paleotidal models complements and enhances stratigraphic and sedimentological methods before being applied to global paleotidal modeling the imperial college ocean model icom is validated for the computation of modern global tides the icom results only deviate slightly from a state of the art published model and were achieved with considerably less computational expense and without data assimilation the results from global paleotidal modeling of the early cretaceous aptian were assessed by comparison with the published geological record icom predicts high mesotidal to macrotidal ranges on the arabian platform around india especially to the north and west along the pacific coast between north and south america northeast of australia and around southeast asia the model predicts low microtidal ranges in the proto south atlantic ocean and weddell sea a further validation test assessed the ability of the model to predict the dominant tidal constituents diurnal or semidiurnal in the aptian lower greensand seaway of southeastern england and northern france during the aptian this region was connected to the boreal proto atlantic and neotethys oceans and now preserves superbly documented tidal deposits the model predicts low microtidal ranges in the proto central atlantic ocean and boreal ocean suggesting that they had little impact on tides in the lower greensand seaway higher tidal amplitudes especially of diurnal once daily tides are predicted in the northwestern neotethys ocean suggesting that this ocean was an important source of tidal energy to the lower greensand seaway sensitivity tests to paleogeographic and paleobathymetric uncertainty indicate that the model predictions are robust the prediction of predominantly diurnal tides is supported by published analyses of large dune scale deposits in the lower greensand of southeast england

seasonal changes in beach morphology along the sheltered coastline of perth western australia abstract seasonal change in beach morphology is traditionally ascribed to a variation in the incident wave energy level with calm conditions in summer resulting in wide beaches with pronounced subaerial berms and energetic conditions in winter causing narrow beaches with nearshore bar morphology the coastline of perth western australia is characterised by a large seasonal variation in the incident wave height and local beaches exhibit a distinct seasonal change in morphology however these morphological changes are better explained by a seasonal reversal in the littoral drift direction than by variations in the incident wave energy conditions in summer when northward sediment transport prevails due to sea breeze activity beaches located south of coastal structures headlands or rocky outcrops become wider due to the accumulation of sediment against the obstacle these beaches will subsequently erode in winter during storms when the longshore sediment transport is toward the south in contrast beaches located north of obstacles will become narrower during summer and wider during winter the usefulness of the dimensionless fall velocity h b w s t where hb is the breaker height ws is the sediment fall velocity and t is the wave period as a predictor of presence absence of bar morphology and beach type was investigated it was found that fluctuates around the threshold of bar formation 1 5 2 over a variety of time scales daily weekly and seasonally these temporal variations in in conjunction with the relatively low wave energy level that characterises the coast negates the development of beach and nearshore morphology that is in equilibrium with the hydrodynamic conditions as a result bar occurrence and beach type can not be readily predicted using along the perth coast

paraglacial adjustment of alluvial fans to the last deglaciation in the snežnik mountain dinaric karst slovenia abstract glaciokarst depressions are major glacigenic depocenters in the dinaric mountain karst areas and often store important information about the timing and nature of glacial processes and paraglacial sediment reworking this study focuses on praprotna draga which is one of the largest glaciokarst depressions in the sne nik mountain dinaric karst with an area of 3 4 km2 and a maximum depth of 140 m the western slopes of the depression are characterized by undulated moraine morphology and alluvial fans are filling its entire floor we present the results on the thickness origin and age of the sediment infill using a complementary geomorphological sedimentological geophysical and dating approach distribution of moraines point to two glacial advances that were associated with two main alluvial fan aggradation phases recognized using the electrical resistivity tomography measurements the youngest alluvial deposits were sampled for cosmogenic 36cl analysis using amalgamated carbonate pebbles the depth profile of 36cl concentrations suggests an age of 12 3 1 7 ka when assuming a likely denudation rate of 20 mm ka 1 since the existence of the younger dryas glaciers in the study area is climatically difficult to explain we tentatively propose that the youngest alluvial deposition in praprotna draga took place after the glacier retreat during the paraglacial period our findings suggest that the time window of paraglacial adjustment in the sne nik mountain was brief and likely conditioned by quick recolonization with vegetation and inefficient surface runoff on deglaciated karst terrain

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

morphodynamics along a micro tidal sea breeze dominated beach in the vicinity of coastal structures abstract the present study investigates the seasonal and interannual morphodynamics on a micro tidal sea breeze dominated tropical beach located in the northern yucatan peninsula mexico the coastal dynamics in the study area are controlled by both local sea breeze and synoptic central american cold surge cacs scale atmospheric events however the net westward littoral drift is dominated by more persistent sea breeze events the field study was conducted along a 2 km stretch of sandy beach located in the vicinity of two coastal structures one hundred beach surveys 2000 beach profiles were undertaken between may 2015 and june 2019 on a weekly and bi weekly basis to investigate beach morphodynamics empirical orthogonal function eof analysis of the morphological features are used to identify the dominant modes of beach variability the first and second spatial eof modes explain the beach long term trend and rotation respectively the first spatial mode is highly influenced by the presence of the structures for all morphological features the second spatial mode associated to beach rotation shows accretion erosion eastward westward of the structures during spring summer fall winter months field observations were employed to correlate the beach response with physical parameters i e water level and wave parameters the long term trend of the shoreline and subaerial volume show no significant correlations with the physical parameters whereas the temporal mode of the high water contour presents a step like behavior which is correlated to the still water level on the other hand beach rotation is highly correlated to the seasonal variability of wave parameters field observations suggest that increase of cacs events activity and water level during el nino 2015 2016 winter season enhanced decreased the beach rotation translation implying a high beach sensitivity to climate variability in this region

microfossil assemblages as key to reconstruct sea level fluctuations cooling episodes and palaeogeography the albian to maastrichtian of boreal and peri tethyan russia

hummocky moraines in the namaras and susam valleys central taurids sw turkey abstract late quaternary glacial features have been found in the central taurid mountains in u shaped valleys located at an altitude of more than 2000 m and surrounded by mountain ranges reaching 2850 m no present day active glaciers exist in this area where the snowline elevation lies at about 3500 m the namaras valley and its tributary susam valley are characterized by coarse loose material forming chaotic knob and kettle topography mounds 1 10 m high and 10 30 m wide are separated by 5 30 m wide several meters deep irregular depressions the upper surfaces of the mounds are covered by angular to subangular limestone pebbles and blocks and internal sediments show a typical diamicton appearance with pebbles suspended in a muddy to sandy matrix these chaotic structures are interpreted as hummocky disintegration moraines from former active glaciers successive cross valley morainic ridges up to 200 m high and several hundreds of meters long limit the down valley extension of these hummocks and are interpreted as ice marginal moraines in the tributary susam valley part of the coarse loose material forms a 200 250 m long and 90 120 m wide tongue shaped structure with successive arcuate ridges and furrows at its down valley reach this structure which is connected upward to a talus slope and perched cirque ressembles the morphology of a periglacial rockglacier but is interpreted as the disintegration moraine controlled by small periodic retreat and readvance of the last active ice front in this region

late mesozoic north atlantic land bridges abstract current palaeogeographical reconstructions suggest that since the onset of the late jurassic and during the whole cretaceous period the landmasses of north america and west eurasia have been separated by seaway s exposed on the north atlantic rift system such a palaeogeographical setting should have limited the possibility of direct overland dispersals between the biotas of the two continents strong faunal affinities between the two sides of the north proto atlantic ocean presuppose faunal exchanges between the landmasses however suggesting the existence of ephemeral land bridges around the jurassic cretaceous boundary and the mid early cretaceous this study reviews the current faunal evidence and discusses palaeogeographical evidence that might better elucidate the existence of the postulated land bridges evaluation of the evidence leads to the conclusion that two land bridges were exposed 1 between east north america and iberia during the late kimmeridgian 154 ma and 2 between north america and fennoscandia via the barents shelf around the hauterivian barremian boundary 131 ma the former land bridge was terminated in the earliest tithonian 151 ma and the latter was terminated in the late early barremian 129 ma furthermore the latter land bridge was contemporaneous with regressive stages in both the mid polish trough and the sea strait crossing the russian platform allowing broad direct terrestrial communication among north america europe and asia in the earliest barremian

sea level reconstructions from the peri vocontian zone south east france point to valanginian glacio eustasy the valanginian is a period of global environmental change as illustrated by sedimentary palaeontological geochemical and climatic perturbations a production crisis in most of the carbonate platforms suggests important changes in palaeoenvironmental conditions during the same time interval a major positive excursion in 13c the weissert event suggests perturbations of the carbon cycle from the latest early valanginian to the early hauterivian in order to better understand the link between these changes sea level fluctuations have been reconstructed in detail from the middle berriasian to the earliest hauterivian sections from the peri vocontian zone south east france have been investigated because of the good quality of outcrops on the carbonate platforms their margins and in the vocontian basin sections ranging from the most proximal zone swiss jura to the basin were interpreted in terms of sequence stratigraphy and cyclostratigraphy and correlated at high resolutions using the identified small medium and large scale sequences as well as depositional geometries sea level fluctuations were reconstructed two main trends are evidenced during the studied interval i the peak amplitude magnitude of the sea level fluctuations increased gradually from the middle berriasian to the early valanginian and reached a maximum more than 50 m from the middle early valanginian to the valanginian hauterivian boundary and ii sea level variations were quite symmetrical during the late berriasian slightly asymmetrical during the early valanginian and strongly asymmetrical fast sea level rise slow fall from the latest early valanginian to the earliest hauterivian moreover three orders of sea level fluctuations were recognized in the sedimentary rocks of the peri vocontian zone platform basin correlations and cyclostratigraphic interpretations of the basinal sections evidence an astronomical control on the sea level variations mainly by the two eccentricity cycles of 100 and 400 kyr the increase in the amplitude of the sea level fluctuations and their change from symmetrical to asymmetrical can be related to the onset of a major cooling event in the early valanginian fast transgressions followed by slower regressions would correspond to waxing and waning of high latitudinal ice during most of the valanginian especially from the latest early valanginian to the latest late valanginian glacio eustatic sea level fluctuations in tune with the 100 and 400 kyr eccentricity cycles are in agreement with glaciations during the valanginian

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

putting the younger dryas cold event into context abstract the younger dryas event is by far the best studied of the millennial scale cold snaps of glacial time yet its origin remains a subject of debate the long held scenario that the younger dryas was a one time outlier triggered by a flood of water stored in proglacial lake agassiz has fallen from favor due to lack of a clear geomorphic signature at the correct time and place on the landscape the recent suggestion that the younger dryas was triggered by the impact of a comet has not gained traction instead evidence from chinese stalagmites suggests that rather than being a freak occurrence the younger dryas is an integral part of the deglacial sequence of events that produced the last termination on a global scale

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

chronology of late pleistocene glacier variations at the uludag mountain nw turkey abstract surface exposure ages with cosmogenic 10be and 26al on glaciogenic landforms at the uludag mountain nw turkey mt uludag 40 04 15 n 29 13 18 e 2542 m above sea level indicate that the local maximum glaciation occurred no later than 20 3 1 5 ka ago this is in agreement with other exposure age data sets from anatolia and is in accordance with the timing of the last maximum glaciation in the european alps coinciding with the global last glacial maximum lgm 21 2 ka geomorphologically constrained subsequent glacier oscillations were dated to the lateglacial period and show distinct phases of readvanced glaciers around 16 1 1 2 ka 13 3 1 1 ka and 11 5 1 0 ka ago this indicates an oscillating glacier recession in nw anatolia during termination 1 published surface exposure ages related to the lateglacial gschnitz and egesen moraines in the european alps are in good agreement with the derived glacier chronology at the uludag mountain this implies the parallel occurrence of major climatic shifts on millennial time scale in the european alps and nw turkey during the marine isotope stage mis 2

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

coastline sand waves on a low energy beach at el puntal spit spain abstract coastline sand waves have been observed at el puntal spit located on the north coast of spain the spit has been monitored by an argus video system since 2003 and the formation and destruction of sand waves has been observed coastline data from the video images are analyzed by means of principal components analysis obtaining a mean sand wave length of 125 150 m and a maximum amplitude of 15 m it is also observed that sand waves reach their maximum amplitude at about 15 days no propagation of these sand waves is noticed during the approximately two month long events analyzed sand wave formation and evolution are examined in relation with the prevailing local wave conditions during that period incident waves at the west end of the spit approach from the east northeast with a very high angle with respect to the shoreline field observations suggest that sand waves may result from an instability in alongshore sediment transport caused by moderate energy waves with a high angle incidence

first cosmogenic geochronology from the lesser caucasus late pleistocene glaciation and rock glacier development in the karcal valley ne turkey abstract evidence of widespread alpine glaciations during the late pleistocene in mid latitudes has long attracted attention of researchers however there were no studies that contain absolute ages in the lesser caucasus despite the fact that it is one of the major glaciated regions in eurasia here we present first cosmogenic 36cl surface exposure ages from the karcal mountains 41 24 n 42 06 e 3431 m a s l above sea level which is located in the most western part of the lesser caucasus in the northeastern anatolia in the karcal mountains there are numerous valleys that have experienced significant glaciations since late pleistocene we have investigated one of the largest valleys the east facing karcal valley that hosts even a small 2926 m a s l recent glacier located at above 3000 m a s l fossil and recent rock glaciers along with lateral and recessional moraines exist in the valley we conducted the study in two stages first we mapped the geomorphological units in the karcal valley in detail based on our field works and aerial photography later we collected 10 rock samples from the fossil rock glacier and recessional moraines for cosmogenic 36cl surface exposure dating the results outline a glacial chronology that is typical of the last glacial maximum although the maximum extent and timing of the glaciation is not exactly known as lateral and terminal moraines were not suitable for sampling recessional moraines indicate that the karcal valley palaeoglacier deglaciation started at least 19 9 1 2 ka ago fossil rock glacier samples were dated to 15 7 1 3 ka these quantitative results are first in the lesser caucasus and compatible with previous ages obtained from other valleys in the nearby eastern black sea region anatolian and some of the european mountains

the southern oscillation index wave climate and beach rotation short embayed beaches bounded by headlands are a common feature along the southern and central coastline of new south wales australia many of these embayed beaches have experienced severe erosion at their southern end over the last decade previous studies have suggested that this erosion may be the result of an oscillatory medium term phenomenon known as beach rotation the present study was undertaken with the objectives of 1 establishing definitive links between the southern oscillation index soi wave climate and beach rotation and 2 determining the physical processes governing beach rotation data from two similar new south wales beaches were analysed using time series analysis techniques and image processing techniques using argus video images in this study the results indicate that the northern end of this type of beach accretes during el nino phases while the southern end erodes resulting in a net clockwise rotation of the beach the opposite occurs during la nina phases resulting in a net anti clockwise rotation of the beach the beach response at the northern and southern ends lags soi trend shifts by 3 and 17 months respectively waves are predominantly incident from the southeast during both el nino and la nina phases offshore wave height is positively correlated with the soi while offshore wave direction is negatively correlated with the soi on average the number of storms per year doubles from el nino to la nina based on these links between beach width fluctuations soi and incident wave conditions a conceptual model of beach rotation is presented the model describes the combinations of cross shore and longshore sediment transport and hydrodynamic processes that are expected to result in the observed clockwise and anti clockwise beach rotation during el nino and la nina phases respectively

remarkably extensive glaciation and fast deglaciation and climate change in turkey near the pleistocene holocene boundary moraines in the taurus mountains of south central turkey dated to latest pleistocene or earliest holocene show that glaciers were extraordinarily large typical of the last glacial maximum 21 ka and that rates of glacier retreat and temperature rise exceeded those of the past century surface exposure ages of 7 moraines in a valley at altitudes between 1100 m and 3100 m above sea level range from 10 2 0 2 ka to 8 6 0 3 ka computed using our own production rates and spatiotemporal scaling factors hitherto unresolved differences in cosmogenic 36 cl production rate estimates can make these ages signifi cantly older and therefore the analysis presented here focuses on the rate of change and not on the absolute chronology during deglaciation the equilibrium line altitude ascended 1430 m and the air temperature rose by 9 c deglaciation occurred in two phases during the second faster phase which lasted 500 yr the glacier length decreased at an average rate of 1700 m 100 yr implying a warming rate of 1 44 c 100 yr indicating a rapid climate shift marking the onset of the holocene in turkey

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

glacier advances in northeastern turkey before and during the global last glacial maximum abstract our study in the basyayla valley in northeastern anatolia showed evidence of four glacier advances that built terminal and lateral moraines surface exposure dating of boulders on these moraines showed that the maximum ice extent mie was asynchronous with the global last glacial maximum lgm 22 1 4 3 thousand years ka the local mie took place at least 57 0 3 5 ka ago the extent of the basyayla glacier during this advance is not known exactly because the boulders are only preserved on a lateral moraine the next advance was prior to 41 5 2 5 ka and it descended down the valley to approximately 2320 m above sea level m a s l with a glacier length of 5 3 km during the early global lgm the basyayla glacier extended for a distance of 4 9 km down to approx 2430 m a s l the last recorded advance occurred during the global lgm this extension was 0 7 km smaller than the local mie and its terminus reached 2490 m a s l only the exposure ages of boulders in a retreat position at an altitude of approx 3045 m a s l indicate that the valley has remained ice free since the lateglacial period therefore the lateglacial extent was limited to the cirque system in the uppermost part of the catchment furthermore holocene glacier oscillations seem to be either absent or restricted to solifluction in the whole catchment and to rock glacier movements in the southern tributary of the basyayla valley system

the younger dryas cold interval as viewed from central greenland abstract greenland ice core records provide an exceptionally clear picture of many aspects of abrupt climate changes and particularly of those associated with the younger dryas event as reviewed here well preserved annual layers can be counted confidently with only 1 errors for the age of the end of the younger dryas 11 500 years before present ice flow corrections allow reconstruction of snow accumulation rates over tens of thousands of years with little additional uncertainty glaciochemical and particulate data record atmospheric loading changes with little uncertainty introduced by changes in snow accumulation confident paleothermometry is provided by site specific calibrations using ice isotopic ratios borehole temperatures and gas isotopic ratios near simultaneous changes in ice core paleoclimatic indicators of local regional and more widespread climate conditions demonstrate that much of the earth experienced abrupt climate changes synchronous with greenland within thirty years or less post younger dryas changes have not duplicated the size extent and rapidity of these paleoclimatic changes

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

the effect of sea breeze on beach morphology surf zone hydrodynamics and sediment resuspension abstract beach morphodynamic processes were investigated over part of a sea breeze cycle on a microtidal low wave energy sandy beach in southwestern australia prior to the onset of the sea breeze offshore winds with speeds less than 5 m s prevailed during the sea breeze alongshore winds with speeds higher than 10 m s were experienced the sea breeze induced pronounced changes to the nearshore morphodynamics which were similar to that of a storm event 1 root mean square wave height increased from 0 3 to 0 5 m 2 zero upcrossing wave period decreased from 8 to 4 s 3 mean cross shore flows reached velocities of 0 2 m s directed offshore and 4 the longshore current increased in strength from 0 05 to 1 0 m s before the sea breeze sediment resuspension typically occurred during isolated high wave events associated with the passage of wave groups flux coupling between the wave oscillatory currents and the suspended sediment jaffe b e sternberg r w sallenger a h 1984 the role of suspended sediment in shore normal beach profile changes proc 19th int conf coastal engineering asce pp 1983 1996 induced net onshore suspended sediment transport resulting in beachface accretion and a steepening of the foreshore profile in contrast during the sea breeze sediment resuspension was almost continuous the suspended sediment load increased six fold and as a consequence the longshore suspended sediment transport rate increased by a factor of 100 during the sea breeze cross shore transport was directed offshore and primarily associated with mean offshore flows this resulted in erosion of the beachface and deposition in the surf zone and consequently a flattening of the beach profile the suspended sediment load was strongly related to the shields parameter defined for the combined action of waves and currents investigation of the suspended sediment profiles indicated that the degree of vertical mixing parameterised by the sediment diffusion coefficient increased with distance from the bed in addition the sediment diffusion coefficient exhibited a large temporal variation ranging between 0 005 and 0 018 m2 s the variability in the sediment diffusion coefficient is possibly due to changes in the sea bed morphology

the deglaciation of the americas during the last glacial termination this paper reviews current understanding of deglaciation in north central and south america from the last glacial maximum to the beginning of the holocene together with paleoclimatic and paleoceanographic data we compare and contrast the pace of deglaciation and the response of glaciers to major climate events during the global last glacial maximum glgm 26 5 19 ka average temperatures decreased 4 to 8 c in the americas but precipitation varied strongly throughout this large region many glaciers in north and central america achieved their maximum extent during the glgm whereas others advanced even farther during the subsequent heinrich stadial 1 hs 1 glaciers in the andes also expanded during the glgm but that advance was not the largest except on tierra del fuego hs 1 17 5 14 6 ka was a time of general glacier thickening and advance throughout most of north and central america and in the tropical andes however glaciers in the temperate and subpolar andes thinned and retreated during this period during the bolling allerod interstadial b a 14 6 12 9 ka glaciers retreated throughout north and central america and in some cases completely disappeared many glaciers advanced during the antarctic cold reversal acr 14 6 12 9 ka in the tropical andes and patagonia there were small advances of glaciers in north america central america and in northern

shoreline variability via empirical orthogonal function analysis part ii relationship to nearshore conditions the method of empirical orthogonal function eof or principal component analysis pca was used to investigate the spatial and temporal variability of shoreline data sets from duck north carolina the gold coast australia and the united states pacific northwest in the present work an attempt is made to relate the individual modes of shoreline variability identified by the eof analyses to select parameterizations of the nearshore environment the parameters considered include the wave energy e the cross shore and longshore wave energy fluxes fx and fy the wave steepness ho lo the non dimensional fall velocity parameter the profile parameter p the surf similarity parameter and a surfzone froude number fr correlation analyses were used to evaluate the linear relationship between each of these parameters and the temporal eigenfunctions ck t associated with individual modes of shoreline change typically strong correlations were observed between longshore uniform modes and the monthly means of several of the nearshore parameters

climate variability in the spanish pyrenees during the last 30 000 yr revealed by the el portalet sequence abstract palynological sedimentological and stable isotopic analyses of carbonates and organic matter performed on the el portalet sequence 1802 m a s l 42 48 00 n 0 23 52 w reflect the paleoclimatic evolution and vegetation history in the central western spanish pyrenees over the last 30 000 yr and provide a high resolution record for the late glacial period our results confirm previous observations that deglaciation occurred earlier in the pyrenees than in northern european and alpine sites and point to a glacial readvance from 22 500 to 18 000 cal yr bp coinciding with the global last glacial maximum the patterns shown by the new high resolution pollen data from this continental sequence chronologically constrained by 13 ams 14c dates seem to correlate with the rapid climate changes recorded in greenland ice cores during the last glacial interglacial transition abrupt events observed in northern latitudes heinrich events 3 to 1 oldest and older dryas stades intra allerod cold period and 8200 cal yr bp event were also identified for the first time in a lacustrine sequence from the central western pyrenees as cold and arid periods the coherent response of the vegetation and the lake system to abrupt climate changes implies an efficient translation of climate variability from the north atlantic to mid latitudes

shoreline dynamics and beach rotation of artificial embayed beaches abstract artificially embayed beaches are an increasingly common environment in retreating and urban coasts the study of embayed beaches usually focuses on the concept of some equilibrium configuration of the shoreline caused by the wave approach and the location of protection structures but detailed studies of their shoreline dynamics are scarce the study reported herein monitored the shoreline dynamics of three artificial embayed beaches in barcelona city during a three year period using an argus video system to examine the behaviour of the emerged beach in order to assess the main factors affecting the shoreline and to analyze the processes causing beach rotation at different time scales the length and degree of protection of the three beaches were different and so were their morphological behaviours two of the beaches presented a general retreating trend with rapid abrupt displacements of the shoreline caused by oblique wave incidence during storm events and to the effects of beach nourishment after nourishment slower changes at the beaches determined beach evolution which was also influenced by the formation of long lasting megacusps the third beach the most protected one showed an accretionary trend no formation of megacusps and episodes of beach rotation related to the gradual recovery of the beach after storm events it is concluded that factors controlling the evolution of barcelona city beaches are associated with both natural processes and man induced actions resulting in a more complex pattern than would be expected for small embayed beaches beach rotation appears as a key process for understanding the morphodynamics of embayed beaches it occurs as a fast response to storms but also as a medium term adaptation of the shoreline configuration to morphological changes in the beach or to the recovery of a more stable orientation after storm events and man made changes in the beach orientation resulting from nourishment or sand relocation

an equilibrium model to predict shoreline rotation of pocket beaches a novel and simple beach evolution model for estimating shoreline rotation at sandy pocket beaches is presented the model is based on the assumption that the instantaneous changes to the planview shape of the shoreline depend on the long term equilibrium planview shape two years of shoreline observations extracted from video images of three artificially embayed beaches of barcelona and hourly wave timeseries are used to validate the model numerical model results and field observations show an excellent agreement with an rmse less than 1 5 m the model successfully reproduced the shoreline response over a range of scales months and years because of its simplicity and its computational efficiency the model provides a powerful tool to understand the dynamics regulating the evolution of pocket beaches and predict temporal patterns in beach rotation

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

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

lateglacial and holocene vegetation belts in the pirin mountains southwestern bulgaria pollen stratigraphy of a core 270 cm long from lake dalgoto at 2310 m in the northern pirin mountains southern bulgaria was treated by optimal partitioning and compared to a broken stick model to reveal statistically significant pollen zones the vegetational reconstructions presented here are based on pollen percentages and pollen influx on comparisons of modern and fossil pollen spectra and on macrofossil dates from other sites in the mountains during the younger dryas 11000 10200 14c yr bp an open xerophytic herb vegetation with artemisia and chenopodiaceae was widely developed around the lake deciduous trees growing at lower elevations contributed to the pollen rain deposited at the higher elevation sampling sites specifically from 10200 to 8500 yr bp quercus ulmus tilia and betula expanded rapidly at low and intermediate elevations and between 8500 and 6500 yr bp they extended to higher elevations close to the upper forest limit which was formed by betula pendula at about 1900 m coniferous species were limited in the region at this time after 6500 yr bp the expansion of conifers pinus peuce p sylvestris p mugo abies alba at high elevations forced the deciduous trees downward between 6500 and 3000 yr bp the forest limit at 2200 m was formed by p peuce and a alba had its maximum vertical range up to 1900 m later the abundance and vertical range of p peuce and a alba were reduced after 3000 yr bp picea expanded

storm response and beach rotation on a gravel beach slapton sands u k abstract continuous argus video data and fortnightly measurements of subaerial morphology were obtained over a 3 year period from a steep macrotidal gravel beach on the southwest coast of the u k concurrent wave and water level data were also collected enabling the correlation of the observed morphological changes to the hydrodynamic forcing wave conditions are generally low h s 0 5 1 m but the beach is affected by frequent storm wave activity c 15 storms per year with h s 2 4 m with waves either approaching from the south swell waves or from the east wind waves an assessment of the three dimensional morphological response of the beach to the two typical storm types was carried out by analysing the impact of 27 storms that occurred from april 2007 to april 2009 southerly storms cause accretion of the supratidal zone and erosion of the intertidal zone and a significant loss in overall beach volume easterly storms on the other hand induce supratidal erosion and intertidal accretion and a significant gain in overall beach volume during the intervening calm periods a small supratidal berm is constructed and a modest gain in overall beach volume occurs wave modelling indicated that opposing longshore energy fluxes occur for the different storm types with a northerly energy flux during southerly storms and a southerly flux during easterly storms weekly shorelines derived from the argus images revealed that the northern end of the beach widened by c 30 m and the middle beach receded by c 40 m over a relatively brief period a few months the occurrence of this beach rotation event is attributed to a higher frequency of southerly storms and or a lower frequency of easterly storms over this period thus the development and stability of the beach on annual time scales depend on the relative contributions of the two storm types and their sequencing longshore sediment transport lst rates derived from the data on beach morphological change were compared with several littoral drift formulae previously applied to gravel beaches the cerc equation with a proportionality factor k between littoral drift rate i l and longshore wave energy flux p l of k 0 054 yielded the best results

global observations of the land breeze 1 four times daily satellite wind observations from the quikscat and adeos ii tandem scatterometer mission are used to study the land sea breeze circulation these observations provide a global view of diurnal wind variations over the ocean results agree with frictional linear theory winds follow an elliptical hodograph through the course of the day but indicate that diurnal wind variations propagate offshore progressively like nonlinear gravity waves and are detectable several hundred kilometers from the coast

cenomanian campanian late cretaceous planktonic assemblages of the crimea caucasus area palaeoceanography palaeoclimate and sea level changes during the cretaceous the crimea caucasus area occupied a position in the peri tethys which was transitional between the boreal and tethyan realms the evolution and stratigraphic distribution of planktonic foraminifera and radiolarians in the upper cretaceous sediments of the region are described the specialized morphologically complex keeled taxa evolved in the latest albian and persisted until the end of the cretaceous these overall evolutionary trends are punctuated by a series of bioevents one of the most important being the cenomanian turonian boundary this is marked by a series of organic rich sediments that are related to an oceanic anoxic event the turonian coniacian interval was marked by a further development of keeled taxa a major change in the assemblage is described near the santonian campanian boundary when marginotruncanids were replaced by globotruncanids the albian is marked by the diversification of the radiolarian genus crolanium the last occurrence of which is typical of the albian cenomanian boundary the upper coniacian to lower santonian strata are characterized by the high taxonomic diversity of the quinquecapsulariidae and the neosciadiocapsidae a marked change in the radiolarian assemblage occurred at the santonian campanian boundary the late santonian warmer water assemblage dominated by the pseudoaulophacidae being replaced in the earliest campanian by cooler water assemblages characterized by the prunobrachidae the changes in the assemblages of planktonic foraminifera and radiolarians at the santonian campanian boundary are attributed to changes in palaeoceanography and the influence of more boreal like conditions three significant episodes of sea level change can be identified in the cenomanian campanian of the crimea caucasus area the first is associated with the albian cenomanian boundary the second at the base of oae2 and the third in the mid early late turonian this latter event had different durations in the crimea and caucasus regions and this could be related to more local tectonic processes

late pleistocene glaciers in greece a new 36cl chronology abstract glaciers formed in the highest mountains of greece during the late pleistocene but the timing of glacier maxima is poorly understood this paper presents 27 36cl terrestrial cosmogenic nuclide exposure ages from glacial boulders on mount tymphi 2497 m a s l 40on in epirus northwest greece these ages address both a significant geographical gap in mediterranean glacial chronologies and a temporal gap in the glacial history of this region by targeting the previously undated late pleistocene record late pleistocene glaciers were restricted to the cirques and upper valleys of mount tymphi terminal and lateral moraines between 1700 m and 2050 m a s l mark the extent of late pleistocene glaciers on the southern side of mount tymphi moraines marking the maximum extent of late pleistocene glaciation date to 29 0 3 0 ka and 25 7 2 6 ka taking the oldest ages as most representative of moraine emplacement glaciers had retreated to the high cirques by 24 5 2 4 ka during heinrich stadial 2 rock glaciers formed under cold and drier conditions during this period of glacier retreat this 36cl dataset complements published u series ages from secondary calcites in glacial sediments below 1700 m elevation which demonstrate more extensive middle pleistocene glaciations in mis 6 and mis 12 a late pleistocene glacier maxima on mount tymphi at 25 7 29 ka is in good agreement with well preserved outwash sediments dating to 24 28 ka in the voidomatis river record downstream and is consistent with the ioaninna basin pollen record indicating cool and wet conditions most favourable for glacier growth at 25 30 ka

isotopic signals from late jurassic early cretaceous volgian valanginian sub arctic belemnites yatria river western siberia this contribution presents the first detailed oxygen and carbon isotope record from the latest jurassic early cretaceous interval of the yatria river subpolar urals siberia isotopic compositions have been determined on well preserved belemnite samples from the genera lagonibelus cylindroteuthis and acroteuthis these new data indicate a shift to lower temperatures from the late volgian into the late valanginian with some warmer phases recognized within the ryazanian and earliest valanginian the lowest temperatures of the late valanginian consistent with subfreezing polar temperatures are coincident with an inferred eustatic sea level fall a late valanginian positive shift in carbon isotopes correlates with the carbon isotope excursion recorded from tethyan successions the most positive carbon isotope values correspond to the most positive oxygen isotope values and hence lowest palaeotemperatures in the absence of widespread valanginian organic rich black shale deposition the carbon isotope excursion may point to increased storage of organic carbon in coastal areas and or enhanced preservation within stratified waters in high latitude basins at these higher latitudes where rates of weathering were presumably much lower because of the prevalent cold climate the isotopic data may point to pulses of productivity being brought about by increased riverine nutrient transfer and also by nutrients being released by the melting of ice the correlation between positive carbon isotopes and cool climates may indicate the effectiveness of these high latitude carbon sinks and their ability to draw down atmospheric co 2 resulting in an inverse greenhouse effect

environmental processes of the ice age land oceans glaciers epilog knowledge of the state of the earth at the last glacial maximum lgm an interval around 21 000 years ago is an important benchmark for understanding the sensitivity of global environmental systems to change much progress in understanding climates of the lgm has occurred in the 20 years since the end of the climap project of the 1970s climate long range investigation mapping and prediction here we review this progress based on presentations and discussion at a rst open science meeting of the epilog project environmental processes of the ice age land oceans glaciers held in delmenhorst germany may 1999 we outline key controversies and document protocols for epilog contributions so that a new synthesis of the lgm earth can emerge as an open project of the world s community of scientists 2001 elsevier science ltd all rights reserved

gastropod egg capsules from the lower cretaceous of russia preserved by calcitization abstract small sized 0 8 1 6 mm in diameter circular to oval three dimensionally preserved calcitized structures have been found embedded within ammonite body chamber moulds from the lower aptian lower cretaceous of russia the characteristic morphology consisting of a flat attachment base and convex upper hemisphere possessing an apical tiny circular opening indicate that these structures represent gastropod possibly caenogastropoda egg capsules originally the egg capsules were attached to the empty shells of the ammonites deshayesites and sinzovia which later were embedded within carbonate concretions the preservation of the egg capsules resulted from both their deposition within a suitable cryptic habitat provided by the empty ammonite shells and the quick cementation of the infilling sediment which not only sufficiently protected the capsules from external environment but also created a suitable closed microenvironment for fossilization the calcitization of the egg capsules may have occurred under low ph conditions in an environment characterized by a very low concentration of phosphorous ions essential for phosphatization so far such structures are known from a few examples derived from different stratigraphic horizons and geographic locations those which are known have been reported in the form of pyritized phosphatized carbonaceous and even bioimmured fossils the calcitized gastropod egg capsules presented here indicate that such structures may in fact be preserved by a wide array of fossilization modes in different paleoenvironments microenvironments thus such fossils seem to be much more common in the fossil record than previously considered

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

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

sub weekly to interannual variability of a high energy shoreline abstract sixty one global positioning system gps sub aerial beach surveys were completed at 7 km long ocean beach san francisco ca usa between april 2004 and march 2009 the five year time series contains over 1 million beach elevation measurements and documents detailed changes in beach morphology over a variety of spatial temporal and physical forcing scales results show that seasonal processes dominate at ocean beach with the seasonal increase and decrease in wave height being the primary driver of shoreline change storm events while capable of causing large short term changes in the shoreline did not singularly account for a large percentage of the overall observed change empirical orthogonal function eof analysis shows that the first two modes account for approximately three quarters of the variance in the data set and are represented by the seasonal onshore offshore movement of sediment 60 and the multi year trend of shoreline rotation 14 the longer term trend of shoreline rotation appears to be related to larger scale bathymetric change an eof based decomposition technique is developed that is capable of estimating the shoreline position to within one standard deviation of the range of shoreline positions observed at most locations along the beach the foundation of the model is the observed relationship between the temporal amplitudes of the first eof mode and seasonally averaged offshore wave height as well as the linear trend of shoreline rotation this technique while not truly predictive because of the requirement of real time wave data is useful because it can predict shoreline position to within reasonable confidence given the absence of field data once the model is developed at a particular site

the spatial and temporal variability of sand bar morphology the spatial and temporal variability of nearshore sand bar morphology is quantified using a unique data set spanning 2 years the data consist of daily time exposure images of incident wave breaking on an open coast sandy beach which may be used to infer bar morphology lippmann and holman 1989 the morphology in each image is classified into an eight state morphologic scheme in which bars are uniquely defined by four independent criteria the most frequently observed morphologies are the longshore periodic rhythmic bars observed in 68 of the data linear bars occur under highest wave conditions h s 1 78 m and are unstable mean residence time 2 days shore attached rhythmic bars are the most stable mean residence time 11 days and generally form 5 16 days following peak wave events non rhythmic three dimensional bars are very transient mean residence time 3 days eighty seven percent of transitions to lower bar types defined in text occurred one state at a time supporting our selection of the ordering of states and suggesting the suitability of a sequential morphology model transitions to higher states occurred under rising wave energy and were evenly spread among the possible higher states with more substantial changes in morphology resulting from larger wave increases this suggests that up state erosional transitions based on offshore bar migration are better described by an equilibrium model where response is better correlated with incident wave energy than with preceding morphological state time exposure images were also digitized to yield quantitative estimates of bar crest location as a function of longshore distance principal component analysis was used to decompose bar position into two dimensional linear and three dimensional longshore variable components cross shore linear bar position ranges 50 m about the 2 year mean 27 m standard deviation and dominates bar variability 74 6 three dimensional bar structure accounts for 14 of the variance 12 m standard deviation changes in incident wave height precede cross shore bar migration by less than 1 day changes in longshore variability are inversely correlated to changing wave conditions with bar morphology becoming linear rapidly during storms on time scales of less than 1 day evolution to significantly three dimensional structure typically occurs over 5 7 days following peak wave events

asynchroneity of maximum glacier advances in the central spanish pyrenees the deglaciation history of the escarra and lana mayor glaciers upper gallego valley central spanish pyrenees had been reconstructed on the basis of detailed geomorphological studies of glacier deposits sedimentological and palynological analyses of glacial lake sediments and an accelerator mass spectrometry ams 14c chronology based on minimum ages from glacial lake deposits the maximum extent of the pyrenean glaciers during the last glaciation was before 30 000 yr bp and pre dated the maximum advances of the scandinavian ice sheet and some alpine glaciers a later advance occurred during the coldest period around 20 000 yr bp synchronous with the maximum global ice extent but in the pyrenees it was less extensive than the previous one later there were minor advances followed by a stage of debris covered glaciers and a phase of moraine formation near cirque backwalls the deglaciation chronology of the upper gallego valley provides more examples of the general asynchroneity between mountain and continental glaciers the asynchroneity of maximum advances may be explained by different regional responses to climatic forcing and by the southern latitude of the pyrenees copyright 2002 john wiley sons ltd

late quaternary alluvial fans of emli valley in the ecemis fault zone south central turkey insights from cosmogenic nuclides abstract alluvial fans within the paraglacial ecemis river drainages on the aladaglar mountains in south central turkey were studied using geomorphological sedimentological and chlorine 36 terrestrial cosmogenic nuclide tcn surface exposure dating methods to examine the timing of alluvial fan abandonment incision and to understand the role of climatic and tectonic processes in the region these alluvial fan complexes are among the best preserved succession of alluvial fans in turkey and they were offset by the major strike slip ecemis fault of the central anatolian fault zone the alluvial fans are mostly composed of well lithified limestone cobbles 5 to 25 cm in size and comprise crudely stratified thick beds with a total thickness reaching up to about 80 m tcn surface exposure dating indicates that the oldest alluvial fan surface yalak fan was likely formed and subsequently abandoned latest by 136 0 23 4 ka ago largely on the transition of the penultimate glaciation marine isotope stage 6 mis 6 to the last interglacial mis 5 i e termination ii the second set of alluvial fan emli fan was possibly developed during the last interglacial mis 5 and incised twice by between roughly 97 0 13 8 and 81 2 13 2 ka ago a younger alluvial fan deposit placed on relatively older erosional terraces of the emli fan suggests that it may have been produced during the last glacial cycle mis 2 these events are similar to findings from other fluvial and lacustrine deposits throughout central anatolia the incision times of the ecemis alluvial fan surfaces largely coincide with major climatic shifts from the cooler glacial periods to warmer interglacial interstadial conditions this indicates that alluvial fans were produced by outwash sediments of paleoglaciers during cooler conditions and later when glaciers started to retreat due to a major warming event the excess water released from the glaciers incised the pre existing fan surfaces an alluvial fan in the study area was also cut by the ecemis fault highlighting the influence of tectonics on fan development it was offset vertically 35 3 m since at least 97 0 13 8 ka which suggests a 0 36 0 06 mm a 1 vertical slip rate of the fault

a reevaluation of coastal embayment rotation the dominance of cross shore versus alongshore sediment transport processes collaroy narrabeen beach southeast australia 1 over 30 years of wave and beach survey data at collaroy narrabeen beach in southeast australia are analyzed to investigate the extent to which shoreline variability within this coastal embayment is dominated by shoreline oscillations due to cross shore sediment exchange or shoreline rotations due to alongshore exchange between the beach s extremities offshore wave data are derived from both buoy measurements and era 40 reanalysis data eof analysis of the monthly shoreline data suggests that the dominant mode of shoreline variability 60 of variability is an onshore offshore sediment exchange that is greater at the more exposed northern end of the beach than at the predominantly sheltered southern end this mode is primarily associated with variability in wave energy storms which by the nature of the wave climate of this region chiefly occurs from the south southeast the secondary mode of shoreline variability 26 of variability is a rotational signal between either end of the beach which coincides with 24 of the offshore wave climate shifting between the south southeast and east as well as changes in the wave period and wave energy storms a distinct annual cycle is identified in this rotation signal it is concluded that alongshore sediment transport processes associated with embayment rotation is more subtle than previously thought and a refined conceptual model of coastal embayment variability in this region is presented highlighting the dominance of cross shore sediment exchange processes

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

shoreline variability via empirical orthogonal function analysis part i temporal and spatial characteristics empirical orthogonal functions eofs or principal components were used to extract the significant modes of shoreline variability from several data sets collected at three very different locations although eofs have proven to be a valuable tool in the analysis of nearshore data most applications have focused on the ability of the technique to describe cross shore or profile variability here however eofs were used to help identify the dominant modes of longshore shoreline variability at duck north carolina the gold coast australia and at several locations within the columbia river littoral cell in the u s pacific northwest in part one of this analysis characteristic patterns of shoreline variability identified by the eof analysis are described in detail at each site the dominant modes consisting of the first four eigenfunctions were found to describe nearly 95 of the total shoreline variability at both duck and the gold coast several interesting longshore periodic features suggestive of sand waves were identified while boundary effects related to natural headlands and navigational structures entrances dominated the pacific northwest data sets

holocene marginal marine ostracod successions from the kizilirmak river delta implications for depositional environments and sea level changes at the southern black sea coast abstract holocene delta formations are unique records of regional sea climate interactions the kizilirmak delta is the biggest and richest wetland ecosystem in the black sea region of turkey the black sea was uniquely affected by rising sea levels due to its disconnection from the world oceans during the last glacial period to understand the palaeoenvironmental impact on the delta plain we analysed a 14 5 m long sediment core using palaeoecological ostracod analyses accompanied by a palaeo salinity reconstruction based on sieve pore analysis on the ostracod cyprideis torosa this study depicts the interplay of terrestrial and marine settings forming mesohaline shallow lagoons and deltaic lakes since ca 7 9 ka cal bp lagoons with mesohaline to polyhaline salinities and mesohaline to oligohaline lake environments were identified reconstructed palaeo sea level estimations depict a remarkable environmental variability the lagoon habitats at 7 9 to 7 0 and 5 3 to 4 ka cal bp were dominated by cyprideis torosa marine influence led to ostracod associations with loxoconcha spp and tyrrhenocythere amnicola especially between 7 9 and 7 0 ka cal bp riverine influence in the same period but especially at about 7 7 ka cal bp caused dominating amnicythere spp cyprideis torosa and candona neglecta that characterise short phases of a mesohaline deltaic lake environment at about 7 7 and 7 0 ka cal bp as well as after 4 ka cal bp with a subsequent salinity decrease c neglecta and later on pseudocandona marchica became dominant with an interruption by another short term lagoonal phase that might be associated with a megadrought between 3 7 and 3 0 ka cal bp

seasonal circulation on the western shelf of the gulf of mexico using a high resolution numerical model 1 the seasonal circulation on the western shelf of the gulf of mexico is studied using a high resolution numerical simulation historical hydrographic data sea level data and satellite images three regions are distinguished the tamaulipas veracruz tave shelf the louisiana texas latex shelf and the western campeche bank on the tave shelf there is a swift reversal of the along shelf current downcoast from september to march and upcoast from may to august when there is upwelling due to offshore ekman transport circulation on the western campeche bank is upcoast throughout the year the latex shelf has a cyclonic circulation except during summer months when the flow is eastward during spring summer the upcoast current on the tave shelf reaches the southern texas shelf where it encounters a downcoast coastal current favoring offshore transports in the fall winter the downcoast current reaches the southern bay of campeche where it meets an opposing along shelf current generating seasonal offshore transports during fall and winter cool low salinity water from the mississippi and atchafalaya rivers is advected westward along the latex shelf onto the tave shelf developing along shelf fronts and temperature inversions commonly observed over the outer shelf and shelf break the main forcing over the western shelf of the gulf is the along coast wind stress component the existence of the cross shelf transports in the confluence regions is supported by chlorophyll a data up to 80 of the seasonal sea level variability is explained by the along shelf currents and the low frequency variability of the atmospheric sea level pressure

onshore sandbar migration in the surf zone new insights into the wave induced sediment transport mechanisms we present a novel process based morphodynamic model which includes transport processes due to both velocity and acceleration skewness and a new formulation for intrawave motions that successfully simulates observations of onshore sandbar migration results confirm findings of previous studies in which each process was considered separately and in which sediment transport was computed from the observed water motion however our results indicate that accounting for the joint action of both velocity and acceleration skewnesses causes major improvement of the modeled onshore bar migration and is essential to accurately model the evolution of the entire cross shore bottom profile when compared with observations we also demonstrate that the morphodynamics in the shoaling zone are dominated by velocity skewness bed shear stresses while sediment transport induced by acceleration skewness pressure gradients controls the morphodynamics in the inner surf zone

multidisciplinary approach for palaeoclimatic signals of the non marine carbonates the case of the sarikavak tufa deposits afyon sw turkey abstract non marine carbonates such as travertine tufa and speleothem are quite sensitive for climatic fluctuations this study presents the new dating and the first pollen records from afyon sarikavak tufas sw turkey together with lithofacies descriptions geochemical and petrographic results obtained from drilling cores sl 2 sl 6 and sl 7 the data extensively provides insight into palaeoenvironmental and palaeoclimatic changes during the middle late pleistocene period according to core samples these fluvial tufa occurrences formed in high gradient and stepped fluvial conditions have been defined as barrage dammed and terraced slope systems in the investigated area the depositional lithofacies are moss tufa included macrophytes bryophytes and vertical stems phytoclastic tufa peloidal tufa micritic tufa microbial tufa intraclastic tufa extra formational tufa lime muddy clay and paleosol level in respectively the new u th radiometric dating and stable isotopes are evaluated together with previously published results in regard to new radiometric data tufa deposits occurred predominantly during the marine isotopic stages at 313 3 21 mis 9 295 8 63 mis 8 9 230 8 42 mis 7d e 228 8 12 mis 7d 215 7 17 mis 7c and 188 2 16 mis 6 7a ka respectively the climatic changes occurring between glacial and interglacial periods such as during the middle late pleistocene might probably influenced the precipitation of tufas in the area in addition the less negative and the more positive carbon isotopic values between 0 8 and 1 3 v pdb could be related to the progressive downstream co2 degassing from host rocks enhanced by high velocity current conditions changes in the soil co2 contribution and photosynthesis the changes of 18o values between 8 3 and 10 1 v pdb are most probably related to variable effects of evaporation in depositional environment palynofloral data gives important clues about the paleovegetation and paleoclimate of the region this field survey has been conducted the first time in this area both carbon values and palynological findings show that drought conditions were dominantly present in the pleistocene period but in some processes drought conditions decreased depending on the amount of rainfall the increasing amount of gymnosperm pollens is more likely to appear in more humid conditions due to the decreasing of drought condition in this time interval

seasonal accretion and erosion patterns of a microtidal sandy beach monthly elevation surveys of a 1 5 km stretch of coast at noordwijk the netherlands were made 1 to quantify seasonal variability in the cross shore position of high mean and low tide contours beach width and beach volume and 2 to examine the dependence of the variability on the offshore wave characteristics additionally daily cross shore positions of contours obtained from video images were used to examine daily beach response to wave characteristics between successive surveys the more intense and frequent storm events in winter than in summer resulted in a seasonal change from a wide beach with a small volume at the end of winter to a narrow large volume beach in summer the seasonal pattern in beach width resulted from the cross shore sediment exchange between the supratidal and lower intertidal part of the beach in contrast to the coupling between beach behaviour and wave characteristics on a seasonal scale beach variability between successive surveys was unrelated to day to week averages of the preceding offshore wave conditions partly due to the precise timing of a storm relative to the two survey moments moreover daily variability determined from the video images showed that differing antecedent morphology to storms and alongshore variations in beach morphology contributed to spatially and temporally variable beach response

first 36cl cosmogenic moraine geochronology of the dinaric mountain karst velež and crvanj mountains of bosnia and herzegovina abstract this article presents the first attempt to date moraines in the dinaric mountain karst using cosmogenic 36cl surface exposure dating technique twenty samples were collected from moraine boulders from two sets of the lowest and largest lateral moraines on the vele 1965 m asl and crvanj mountains 1920 m asl in bosnia and herzegovina the dated lateral terminal moraine complexes spanning elevations from 980 to 1350 m asl are up to 2 7 km long and rise more than 100 m above the valley floor the moraine boulders yielded 36cl ages spanning from oldest dryas for vele 14 9 1 1 ka to younger dryas for crvanj 11 9 0 9 ka considering the average age of the two oldest samples from each lateral moraine as the most representative time of moraine emplacement the dated moraines mark the largest extent of glaciers in both study areas which have been reconstructed to 28 km2 for vele and 24 km2 for crvanj having a mean equilibrium line altitude at 1388 m and 1541 m respectively under modern precipitation values which account for 2000 mm the temperature depression between 8 and 10 c is required to sustain the palaeoglaciers with reconstructed equilibrium line altitudes glaciers of similar size with such low equilibrium line altitudes during the lateglacial have not been reported until now for the balkan peninsula it is very likely that the boulder ages reflect complex exhumation and denudation histories which at this point do not allow obtaining more precise moraine chronologies for the study areas nevertheless this article delivers new data on the extent and timing of quaternary glaciations in the mediterranean mountains where records of glacier fluctuations seem to be asynchronous amongst different areas it is clear that dating moraines with cosmogenic 36cl surface exposure dating in carbonate lithologies in areas of high precipitation like the dinaric karst remains challenging

medium term variations of bar properties and their linkages with environmental factors at hasaki japan beach profile data obtained every weekday for 15 years along a 427 meter long pier were analysed by complex empirical orthogonal function analysis the seaward bar migration was represented by the first mode and the migration frequency and the temporal variation of the bar amplitude were estimated with the complex time coefficient of the first mode although the seaward bar migration frequency which is the reciprocal of the duration time of the bar migration cycle was relatively constant before 1993 and ranged between 1 3 to 0 8 cycles year 0 7 to 1 25 years cycle it gradually decreased after 1994 and reached 0 1 cycle year 10 years cycle at the end of 1996 subsequently it gradually recovered to the frequency before 1993 the bar amplitude had a similar long period fluctuation it was large before 1993 but small from 1995 to 1997 and then returned to the pre 1993 value the bar migration frequency was weakly correlated with the bar amplitude and the offshore wave energy flux

timing of the last glacial maximum from observed sea level minima during the last glacial maximum ice sheets covered large areas in northern latitudes and global temperatures were significantly lower than today but few direct estimates exist of the volume of the ice sheets or the timing and rates of change during their advance and retreat here we analyze four distinct sediment facies in the shallow tectonically stable bonaparte gulf australia each of which is characteristic of a distinct range in sea level to estimate the maximum volume of land based ice during the last glaciation and the timing of the initial melting phase we use faunal assemblages and preservation status of the sediments to distinguish open marine shallow marine marginal marine and brackish conditions and estimate the timing and the mass of the ice sheets using radiocarbon dating and glacio hydroisostatic modelling our results indicate that from at least 22 000 to 19 000 calendar years before present land based ice volume was at its maximum exceeding today s grounded ice sheets by 52 5 x 10 exp 6 cu km a rapid decrease in ice volume by about 10 percent within a few hundred years terminated the last glacial maximum at 19 000 250 years

cretaceous palaeogeography of the north eastern peri tethys abstract the cretaceous stratigraphy and main palaeogeographic features of the north eastern peri tethys are briefly summarised on the base of new data the study is mainly focused on the time slices that were chosen for the recently published peri tethys atlas early hauterivian early aptian late cenomanian early campanian and late maastrichtian two main epochs in the development of this area are recognised the early cretaceous is characterised by the prevalence of the terrigenous sedimentation and the existence of a large longitudinal strait through the russian platform which controlled the boreal tethyan connection the southward boreal water movement prevailed during the neocomian the strongest boreal transgression took place in the late hauterivian when cool water reached the crimea basin the aptian albian time was characterised by a northward tethyan water movement interrupted by the early albian boreal transgression tectonic rebuilding of the region took place in the albian cenomanian it resulted in the disappearance of the sea strait through the russian platform and in the opening of another sea strait in the turgai area in the turonian this strait connected the peri tethyan seas the western siberia boreal basin and joined with the western interior seaway in the other side of the hemisphere the northern hemisphere megastrait appeared during this time mainly carbonate sedimentation prevailed but the existence of a new longitudinal strait determined a two way water and faunal exchange tethyan water moved up to the south and the south east parts of the western siberian basin while the cold boreal water influence can be recognised along the northern margin of the russian platform basin

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

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

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

morphodynamic variability of high energy macrotidal beaches cornwall uk abstract spatial data collected over three years are presented to assess the extent of morphological variability under seasonal and storm waves on two high energy macrotidal beaches on the north cornish coast of particular interest was the degree to which the beaches displayed bar rip morphology and a novel approach to quantify the three dimensionality of the beach based on the curvature of the bottom contours is adopted to identify and classify the three dimensional beach response to changes in the dominant forcing conditions morphologically the beaches range from dissipative to intermediate and are characterised by low tide bar rip morphology which plays a key role in the nearshore dynamics and beach safety real time kinematic rtk gps surveys were undertaken using an all terrain vehicle to measure the three dimensional 3d morphology in addition nearshore wave data in situ hydrodynamic measurements local tide gauges and argus video data allowed detailed analysis of process response mechanisms for long term yearly seasonal monthly storm weekly daily and tidal hourly morphological behaviour both sites exhibited net long term accretion derived from the intertidal beach volume throughout the survey period inter site similarity in beach response was observed in response to storm waves yet coupling between the seasonal wave climate and the beach morphology was not evident at either of the sites increased wave conditions exceeding hs 4 m during sustained storm events 50 h led to offshore transport from the beachface to the subtidal bar region post storm recovery was characterised by onshore transport and the development of substantial 3d low tide morphology under normal wave conditions hs 1 6 m the dominant 3d features smoothed out as channels in filled and bar prominence reduced over a period of 2 3 months overall the beaches exhibited a significant storm dominated morphological response cycle unlike the more familiar winter summer seasonal response

surface exposure dating of late pleistocene glaciations at the dedegol mountains lake beysehir sw turkey situated on the interior side of the western central taurus mountains of sw anatolia the muslu valley in the dedegol mountains mt dipoyraz 37 37 07 n 31 19 42 e 2992 m above sea level a s l represents the lower part of a formerly glaciated valley system of 7 5 km in length surface exposure ages with cosmogenic 10be and 26al date a glacier expansion out of the muslu valley 24 3 1 8 ka ago 1 confidence interval and give evidence for pronounced glacier advances prior to the global last glacial maximum lgm 21 2 ka deglaciation commenced no later than 17 7 1 4 ka ago superimposed climatic oscillations are indicated by glacier fluctuations dated around 19 8 1 6 ka and again 13 9 2 3 ka prior to the first major amelioration of climate the late pleistocene glacier chronology from the western central taurus mountains published lake level fluctuation data of palaeolake konya and lake beysehir and nearby pollen data on the central anatolian plateau reveal a conspicuous time correlation of palaeoenvironmental change copyright 2009 john wiley sons ltd

new insights into embayed beach rotation the importance of wave exposure and cross shore processes although embayed beach rotation has been viewed and modeled as an alongshore sediment transport process acting on a uniform beach profile recent research suggests a more complex response whereby alongshore variability in cross shore sediment fluxes may be more significant this study utilizes 5 years of fully three dimensional beach surveys at narrabeen collaroy beach se australia to quantify the control of alongshore nonuniform wave exposure and cross shore processes on embayed beach rotation empirical orthogonal function analysis of the alongshore variability in subaerial beach volume width and berm slope confirms that the dominant mode of subaerial beach variability is an onshore offshore sediment exchange that is strongly controlled r 0 8 by the alongshore gradient in breaker wave height and coincides with a uniform flattening steepening of the berm slope a secondary rotation like signal is observed in both the subaerial beach volume width data and significantly the berm slope this inverse flattening steepening of the berm slope between beach extremities is most likely a proxy for differing cross shore processes within the surf zone between the exposed and sheltered ends of the embayment particularly with regards to dissipation of storm wave energy by offshore sandbars and beach recovery following storms analysis of the corresponding wave data reveals two distinct time scales of wave forcing characteristic of short term erosion and longer term recovery processes a new conceptual model is presented of three differing modes of embayed beach rotation with the newly identified beach rotation mode controlled by offshore sandbars considered of particular importance at embayments where headland sheltering of oblique waves is pronounced

the upper valanginian early cretaceous positive carbon isotope event recorded in terrestrial plants our understanding of the ancient ocean atmosphere system has focused on oceanic proxies however the study of terrestrial proxies is equally necessary to constrain our understanding of ancient climates and linkages between the terrestrial and oceanic carbon reservoirs we have analyzed carbon isotope ratios from fossil plant material through the valanginian and lower hauterivian from a shallow marine ammonite constrained succession in the crimean peninsula of the southern ukraine in order to determine if the upper valanginian positive carbon isotope excursion is expressed in the atmosphere d 13 cplant values fluctuate around 23x to 22x for the valanginian hauterivian except during the upper valanginian where d 13 cplant values record a positive excursion to 18x based upon ammonite biostratigraphy from crimea and in conjunction with a composite tethyan marine d 13 ccarb curve several conclusions can be drawn 1 the d 13 cplant record indicates that the atmospheric carbon reservoir was affected 2 the defined ammonite correlations between europe and crimea are synchronous and 3 a change in photosynthetic carbon isotope fractionation caused by a decrease in atmospheric pco2 occurred during the upper valanginian positive d 13 c excursion our new data combined with other paleoenvironmental and paleoclimatic information indicate that the upper valanginian was a cool period icehouse and highlights that the cretaceous period was interrupted by periods of cooling and was not an equable climate as previously thought d 2005 elsevier b v all rights reserved

age dating and the orbital theory of the ice ages development of a high resolution 0 to 300 000 year chronostratigraphy using the concept of orbital tuning a continuous high resolution deep sea chronostratigraphy has been developed spanning the last 300 000 yr the chronology is developed using a stacked oxygen isotope stratigraphy and four different orbital tuning approaches each of which is based upon a different assumption concerning the response of the orbital signal recorded in the data each approach yields a separate chronology the error measured by the standard deviation about the average of these four results which represents the best chronology has an average magnitude of only 2500 yr this small value indicates that the chronology produced is insensitive to the specific orbital tuning technique used excellent convergence between chronologies developed using each of five different paleoclimatological indicators from a single core is also obtained the resultant chronology is also insensitive to the specific indicator used the error associated with each tuning approach is estimated independently and propagated through to the average result the resulting error estimate is independent of that associated with the degree of convergence and has an average magnitude of 3500 yr in excellent agreement with the 2500 yr estimate transfer of the final chronology to the stacked record leads to an estimated error of 1500 yr thus the final chronology has an average error of 5000 yr