vegetation and environmental changes in northern anatolia between 134 and 119 ka recorded in black sea sediments this multiproxy study on se black sea sediments provides the first detailed reconstruction of vegetation and environmental history of northern anatolia between 134 and 119 ka here the glacial interglacial transition is characterized by several short lived alternating cold and warm events preceding a meltwater pulse 130 4 131 7 ka the latter is reconstructed as a cold arid period correlated to heinrich event 11 the initial warming is evidenced at 130 4 ka by increased primary productivity in the black sea disappearance of ice rafted detritus and spreading of oaks in anatolia a younger dryas type event is not identifiable the eemian vegetation succession corresponds to the main climatic phases in europe i the quercus juniperus phase 128 7 126 4 ka indicates a dry continental climate ii the ostrya corylus quercus carpinus phase 126 4 122 9 ka suggests warm summers mild winters and high year round precipitation iii the fagus carpinus phase 122 9 119 5 ka indicates cooling and high precipitation and iv increasing pinus at 121 ka marks the onset of cooler drier conditions generally pollen reconstructions suggest altitudinal latitudinal migrations of vegetation belts in northern anatolia during the eemian caused by increased transport of moisture the evidence for the wide distribution of fagus around the black sea contrasts with the european records and is likely related to climatic and genetic factors

quantifying climatic change through the last glacial interglacial transition based on lake isotope palaeohydrology from central turkey questions remain as to the nature of climatic change through the last glacial interglacial transition in the eastern mediterranean region particularly the relative contribution of evaporation and precipitation to regional water balance here changes in oxygen isotope values through this time period from eski acigol a crater lake in central turkey are investigated using hydrological and isotope mass balance models these allow changes in evaporation and precipitation to be quantified and their relative importance evaluated we show that it is the volumetric flux rate of water passing through the lake system and not the precipitation to evaporation ratio per se which controlled the stable isotope record in eski acigol early holocene precipitation is shown to be much greater than that during both the latter part of the last glaciation and the present day we test these calculated values against other records in the same region firstly with other lake records in anatolia the konya basin and lake van and secondly with isotope inferred palaeo precipitation data from soreq cave in israel this reveals a contrast between pre and post lgm precipitation values in turkey wetter and drier respectively and also suggests that during the last glacial interglacial transition there was a more marked precipitation gradient than at present between northern interior and southern coastal parts of the eastern mediterranean region

slip along the sultanhani fault in central anatolia from deformed pleistocene shorelines of palaeo lake konya and implications for seismic hazards in low strain regions

environmental impacts of ancient copper mining and metallurgy multi proxy investigation of human landscape dynamics in the faynan valley southern jordan the environmental impact of mining and metallurgy is an issue that has affected societies in the ancient near east over the past 8000 years we present the results of a multidisciplinary project using agricultural sediments from ancient terraces as a cultural archive of environmental pollution and land use in the copper ore rich faynan valley of southern jordan due to the simultaneous production of agricultural goods and copper metallurgy throughout the last 6000 years in the valley environmental pollution and its consequences for human health have been considered as a factor in settlement abatement sediments from two farming terrace systems adjacent to the major mining and smelting locales were analyzed the sediment analyses included metal concentrations lead isotopes and phytolith analysis and osl dating although measurable concentrations of lead and other heavy metals persist in ancient metallurgical waste piles our investigations found minimal evidence for contamination in the adjacent terrace systems based on these results we argue that the occurrence of environmental pollution in the faynan valley is highly variable and that the distribution of heavy metals resulted from a combination of natural and cultural factors including persistent landscape features that helped contain the most polluted metallurgical deposits these findings are significant for understanding the processes of landscape change and human impacts on desert environments including the ways in which past human actions have negatively affected the environment as well as preserved and protected the environment from further degradation

vegetation and climate during the last glacial high stand ca 28 22 ka bp of the sea of galilee northern israel abstract despite ongoing discussions on hydroclimatic conditions in the southern levant during the last glacial detailed knowledge about the levantine paleovegetation which is an important indicator for the paleoclimate is limited to investigate the paleovegetation in northern israel we analyzed the pollen assemblage of a sediment core that was drilled at the ohalo ii archaeological site on the southwestern shore of the sea of galilee lake kinneret we refined the lithology and the age depth model with the help of five new radiocarbon dates the core comprises a continuous sediment profile of mainly laminated authigenic calcites and detrital material that deposited between ca 28 000 and 22 500 years before present when the sea of galilee rose above the modern lake level stand and temporarily merged with lake lisan the precursor of the dead sea the well dated and high resolution pollen record suggests that steppe vegetation with grasses other herbs and dwarf shrubs predominated in northern israel during the investigated period in contrast to the holocene there was no continuous vegetation belt of the mediterranean biome in the vicinity of the sea of galilee mediterranean elements such as deciduous oaks only occurred in limited amounts and were probably patchily distributed these results disagree with previous pollen based hypotheses from the region that assumed the spread of mediterranean forest during glacial periods while the pollen data may indicate semiarid conditions in northern israel and give no evidence of increased effective moisture previous hydroclimatic studies suggested increased precipitation rates that are consistent with high lake levels sea of galilee lake lisan thus we discuss factors influencing the pollen assemblage and the plant cover

environmental implications of salt facies in the dead sea thick sequences of salt halite have been recovered in a 456 m long core drilled at the deepest floor of the dead sea by the dead sea deep drilling project and extending 200 k y back in time the salt sequences were precipitated in the ancient lake that occupied the dead sea basin during the last three interglacials during intervals of extreme aridity in the lake s watershed the salt layers alternate with mud layers that indicate wetter periods in the watershed when floods transported fine detritus matter to the lake the salt sources include brine discharge and freshwater runoff that dissolved halite units dissolved salts accumulated in the lake during glacials and relatively wet periods when the lake expanded and precipitated during interglacials when the lake levels dropped this study establishes for the first time the evaporite facies and sedimentological features of the deep dead sea brine during interglacial periods by using the modern precipitation of halite in the dead sea as an analogue for past halite depositional periods as recorded in the drill core the halite intervals provide a record of facies characterizing a deep water evaporitic environment the halite layers consist mainly of two types of crystals small cumulate crystals containing halite rafts which indicate precipitation from the surface brine of the lake epilimnion and bottom growth usually large halite crystals that precipitated on the lake floor hypolimnion the layers of small halite crystals formed during drier periods as compared to the bottom growth crystals the bottom growth halite crystals contain variable quantities of detritus and show mild dissolution structures at the contact between the mud and the halite crystals these two main types of halite in combination with muds and gypsum comprise seven categories of salt facies that reflect the hydrological conditions dry to wet and that display a cyclic decadal to millennial pattern along the sampled core intervals frequent alternation of these two salt crystal types suggests seasonal changes whereby the small cumulate crystals were formed during the summer and the bottom growth crystals were formed during the winter when the surface temperatures of the lake were low and the surface water was less saline and less likely to be saturated with respect to halite comparison of the last interglacial halite with the modern halite facies together with the absence of significant dissolution features within the halite and the cyclic nature of the facies indicates that the lake was continuously deep 100 m during the last 200 k y

the applicability of trace elements in freshwater shells for paleogeochemical studies experimental studies on modern aragonitic shells of the gastropods melanopsis praemorsum and m tuberculata yielded bulk distribution coefficients of 0 31 for sr and of 0 48 for ba between the shells and their ambient waters these partition coefficients are about three times lower than their inorganic equivalents h2o leaching experiments of modern shells indicate that sr and ba dissolve congruently with no effect on the original sr and ba contents of the shells conversely the na ca mg ca and k ca ratios in the shells and in the extrapallial fluids are constant independent of variations in the habitat water chemistry this vital effect dominates the shell composition regarding the latter three ion ratios moreover dissolution experiments suggest that there is leaching of a significant fraction of na mg and k which is presumably not bound to the mineral s lattice this preferential dissolution starts before any mineralogical alteration occurs the laboratory data are supported by a sharp decrease of the na ca ratio observed in aragonitic fossils during early diagenesis in contrast with its constancy in live specimens these results clearly demonstrate that sr and ba can be used for environmental studies whereas na mg and k cannot

first evidence of a distal early holocene ash layer in eastern mediterranean deep sea sediments derived from the anatolian volcanic province article i nfo a hitherto unknown distal volcanic ash layer has been detected in a sediment core recovered from the southeastern levantine sea eastern mediterranean sea radiometric stratigraphic and sedimentological data show that the tephra here termed as s1 tephra was deposited between 8970 and 8690 cal yr bp the high silica rhyolitic composition excludes an origin from any known eruptions of the italian aegean or arabian volcanic provinces but suggests a prevailing central anatolian provenance we compare the s1 tephra with proximal to medial distal tephra deposits from well known mediterranean ash layers and ash fall deposits from the central anatolian volcanic field using electron probe microanalyses on volcanic glass shards and morphological analyses on ash particles we postulate a correlation with the early holocene dikkartin dome eruption of erciyes dag volcano cappadocia turkey so far no tephra of the central anatolian volcanic province has been detected in marine sediment archives in the eastern mediterranean region the occurrence of the s1 tephra in the south eastern part of the levantine sea indicates a wide dispersal of pyroclastic material from erciyes dag more than 600 km to the south and is therefore an important tephrostratigraphical marker in sediments of the easternmost mediterranean sea and the adjacent hinterland

new insights into the palaeoenvironmental evolution of magdala ancient harbour sea of galilee israel from ostracod assemblages geochemistry and sedimentology abstract despite several studies have focused on the past bio sedimentary response of the mediterranean coastal areas to ancient seaport activities only few geoarchaeological and palaeoecological data are available on strictly lacustrine harbours to date at the archaeological site of magdala taricheae sea of galilee north israel an interdisciplinary study combining ostracod fauna composition and shell chemistry with sedimentology geochemistry of sediments and archaeological data was undertaken on the sedimentary succession buried beneath the roman harbour structures in correspondence of two key sections this approach provided detailed information about past environmental changes otherwise not visible into a high resolution pottery based chronological framework at the transition from a natural pre harbour to anthropogenically influenced harbour lacustrine depositional setting new bio sedimentary and archaeological pottery data document that remarkable hydrodynamic and hydrochemical changes took place during the hellenistic period from the 3 rd 2 nd century bc to the first half of the 1 st century ad in response to the construction of the oldest magdala harbour installations and possibly to the following hasmonean structures the high v cr concentrations observed in the harbour sediments and the substantial increase of ostracod species pseudocandona albicans preferring slow moving waters and fine grained substrates point to the establishment of a semi enclosed shallow and organic rich setting coupled ostracod geochemical analyses also testify to an alkali ions na and k enrichment within whole sediment samples reasonably driven by increasing evaporation in response to the partial isolation of the lake margin the increase in sodium and potassium concentrations is accompanied by the sudden appearance of heterocypris salina a brackish tolerant species and by the almost absolute dominance of noded valves of cyprideis torosa whose shells are enriched in na k and cl the positive covariance between na 2 o k 2 o values and the frequencies of noded c torosa seems to confirm the relation between node development and changes in ionic concentration within hypohaline settings

lake van deep drilling project paleovan a complete succession of the lacustrine sediment sequence deposited during the last 600 000 years in lake van eastern anatolia turkey was drilled in 2010 supported by the international continental scientific drilling program icdp based on a detailed seismic site survey two sites at a water depth of up to 360 m were drilled in summer 2010 and cores were retrieved from sub lake floor depths of 140 m northern basin and 220 m ahlat ridge to obtain a complete sedimentary section the two sites were multiple cored in order to investigate the paleoclimate history of a sensitive semi arid region between the black caspian and mediterranean seas this introductory paper provides background information of the deep drilling project and an overview of the studies presented in this special volume by the paleovan science team dealing with chronology paleomagnetism paleoenvironmental proxies geophysical and petrophysical investigations as well as pore water and fluid transport

paleohydrology of lake kinneret during the heinrich event h2 abstract during the last glacial period lake kinneret the sea of galilee fluctuated between high and low water levels reflecting the hydrological conditions of the lake watershed here we focus on the hydrology of the lake after its retreat from the last glacial mis2 27 25 ka bp highest stand of 170 m below mean sea level m bsl to the low stand of 214 m bsl at 24 21 ka bp the limnological hydrological history of this time interval is recovered from trench and borehole that were dug and drilled in the southwestern shore of the lake at ohalo ii archeological site cyprideis torosa ostracoda recovered from the trench yielded elemental 87sr 86sr and 18o isotope data that provide information on the shore environment during the low stand period the 87sr 86sr and sr ca ratios in the ostracods varying between 0 70789 and 0 70815 and 0 0017 and 0 0030 respectively indicate contributions of waters from the last glacial lake and regional runoff the increase in the 87sr 86sr ratios reflects the decreasing effect of the last glacial lake kinneret waters and enhanced contribution of local runoff that washed down dried mountain soils that were previously developed during the wet and vegetated glacial the lake retreat at 24 ka bp coincided with the heinrich event h2 at the northern atlantic h2 was expressed by severe aridity in lake kinneret dead sea watershed the limnological hydrological change at post h2 was accompanied by 2 decrease in the 18o value from 2 to 4 reflecting the change in the composition of the east mediterranean rain sources the last glacial lake 87sr 86sr ratio is similar to the tiberias spa saline waters and distinctly different from the modern lake kinneret fresh waters 87sr 86sr 0 70785 compared to 0 70760 respectively this difference is explained by enhanced contribution of ca chloride brines with high 87sr 86sr values to the last glacial lake and reduced jordan river contribution due to cold freezing conditions at its headwaters while the modern lake kinneret is more affected by low 87sr 86sr freshwater from the jordan watershed

internal structure of the dead sea leaky transform rift in relation to plate kinematics abstract the structures along the dead sea transform rift are related to the motions of the sinai and arabia plates which border it and to the irregularities of their boundaries the total slip was 105 km left lateral but the present structures were formed mainly during the last 40 km of slip which probably occurred in the plio pleistocene along the southern half of the transform the strike slip motion takes place on en echelon faults this produces rhomb shaped grabens or pull aparts which are sometimes composite and in which there is local crustal separation thus much of the transform is leaky these structures occur in a morpho tectonic rift valley delimited by normal faults which express a small component of transverse extension along a few segments the shape of the transform is such that lateral motion produces local transverse compression the geometric relations of the structures along the transform define an eulerian pole of relative plate motions at 32 8 n 22 6 e 0 5 the older motion was somewhat different and is described by a pole located about 5 west of the above then the component of transverse extension and crustal separation was much smaller than now while local transverse compression was more important the northern half of the dead sea transform has an irregular shape and the bordering plates did not remain rigid as lateral motion continued here transverse compression is often important

faunal turnover in the azraq basin eastern jordan 28 000 to 9000 cal yr bp signalling climate change and human impact recent zooarchaeological analyses of game exploitation in the epipalaeolithic of the southern levant identify a decline in large game in the natufian with corresponding increase in small prey interpreted as hunting pressure driven by population expansion to date studies focus on the mediterranean zone this paper adopts similar approaches to examine epipalaeolithic to neolithic faunal data from 16 sites in the steppic jordanian azraq basin results here reveal very different trends large game mainly equids fluctuate throughout the epipalaeolithic due to climatic conditions and available water vegetation cattle thrive in the azraq oasis showing no decline in the late epipalaeolithic gazelle exploitation is predominant and sustainable throughout the epipalaeolithic even at kharaneh iv and wadi jilat 6 megasites however ppnb assemblages from the limestone steppe show intensive game exploitation resulting from longer stay settlement the focused gazelle hunting camp at dhuweila in the basalt desert also shows pressure from indiscriminate culling impacting herd demography interpreted as providing meat for onwards exchange human impacts on steppe fauna appear both local and in many cases short term unlike the large game suppression reported from west of the rift valley resource pressures and game over kill whether population driven or otherwise are not currently apparent east of the jordan river

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

the use of acoustic imaging to reveal fossil fluvial systems a case study from the southwestern sea of galilee abstract the analysis of reflected high resolution seismic data shows a distinct separation of regions with good and poor seismic penetration additional analysis of core data revealed good correlation between grain size and seismic penetration as a case study a shallow geophysical survey using a chirp profiler was conducted in the southwestern part of the sea of galilee by correlating the seismic and core data we found that areas with good seismic penetration represent coarse clastics while poor seismic penetration is related to fine clays new detailed bathymetric mapping and bottom morphology images combined with the penetration characteristics of the chirp signal reveal a large alluvial fan consisting mainly of coarse material sand to pebbles a fine grained band of mostly clay size material associated with an asymmetric bathymetric channel continues the trend of the old entrance of the yavniel creek into the sea of galilee we interpret the fine clay stripe to be a low energy streambed of the yavniel creek the clear relations between the reflected chirp signal and the grain size of the water bottom sediments suggests that this type of survey can be used to characterize depositional environments

catastrophic arid episodes in the eastern mediterranean linked with the north atlantic heinrich events the response of continental climate to the well documented climate oscillations during the last glacial period has been a subject of intense interest yet much less is known about the influence on regional continental climates than in the marine or polar realms of earth the detailed lake level history of the closed lake lisan paleo dead sea in the middle east has been reconstructed from shoreline indications and high resolution u th and 1 4 c chronologies thus providing data on the response of the lake s catchment area to the climate changes during the corresponding period we present a correlation between the newly developed lake lisan level curve for the past 55 k y and the north atlantic heinrich events the correlation indicates a closely connected climate response between these north atlantic events and the hydrologic conditions that prevailed in the eastern mediterranean our findings show that although the generally cooler conditions that prevailed during the last glaciation favored high levels of the lake catastrophic events in the north atlantic which are associated with maximum cooling have been responsible for droughts in the eastern mediterranean we infer that cold water input to the mediterranean originating in the collapse of the north atlantic deep water circulation caused the reduction of evaporation and less precipitation in the eastern mediterranean

hypersaline brine diagenesis and evolution in the dead sea lake lisan system israel abstract water soluble salts were extracted from 57 aragonite and detrital laminae sampled from the pleistocene lake lisan sediments the solutions and solids were analysed for ca mg na k sr cl so 4 and bicarbonate average na cl mg ca sr ca mg cl ca cl sr cl k cl k na and k mg ratios calculated for seven stratigraphie elevations in the lisan column indicate that the dead sea rift sediment brine system has remained practically closed for 70000 years the soluble salts reflect both the hydrologie evolution of the lake as well as diagenetic processes mg ca ratios systematically decrease in younger sediments and this decline is accompanied by a 1 5 4 fold sr enrichment in aragonite solubles relative to salts extracted from detrital laminae the major process responsible for these observations is dolomitization of sr rich aragonite by interstitial brine diagenesis was triggered by slow desiccation of the lake s sediments after the lisan waters started to recede due to a change in climate very sharp chemical gradients which developed in the sediments after deposition have been preserved because further diagenesis was quenched by the advancing dry out h 2 o loss by evaporation induced difrusional migration of na and cl from aragonite laminae into adjacent detrital layers this lowered the na cl ratio in the aragonite and raised it in the detritus relative to the initial dead sea na cl ratio of 0 26 the early lisan brine was similar in its chemical composition and total salinity to that of the present dead sea

last glacial holocene temperatures and hydrology of the sea of galilee and hula valley from clumped isotopes in melanopsis shells abstract the carbonate clumped isotope 47 thermometer was applied to fresh water snails melanopsis spp grown in the waters of the sea of galilee and hula valley in the north of israel modern shells grown at known temperatures agree with the 47 t calibration of zaarur et al 2013 fossil melanopsis shells from 2 locations gesher bnot ya aqov at the southern tip of the hula valley and the sea of galilee provide a temperature record for the region during the time interval of the past 20 kyrs glacial temperatures are 5 c cooler than mid holocene and 3 c cooler than modern similar to other records in the region these 47 derived temperatures are combined with 18o of the shell carbonate to calculate the oxygen isotopic composition of the habitat waters contrary to global trends and other regional records reconstructed 18owater values increase from the late glacial through the holocene this reversed signal reflects a decrease in the relative contribution of snowmelt to the watershed post lgm and a transition to a more rain dominated inflow a fairly constant difference in 18owater values between the hula valley and sea of galilee waters suggests that the hydrological relationship of the two water bodies had remained constant with the temperature changes playing only a minor role in the extent of evaporation of the sea of galilee relative to the hula

modifying the marsh evaluating early epipaleolithic hunter gatherer impacts in the azraq wetland jordan the ecological impacts of human activities have infiltrated the whole of the natural world and precipitated calls for a newly defined geological epoch the anthropocene while scholars discuss tipping points and scale viewed over the longue duree it is becoming clear that we have inherited the compounding consequences of a constructed environment with a long history of human landscape modification by linking phytolith and micro charcoal evidence from sediments in the azraq basin jordan we discuss potential early epipaleolithic 23 000 17 400 cal bp human environment interactions in this wetland our analyses reveal that during the last glacial maximum levantine hunter gatherers could have had a noticeable and increasing impact on their environment however further work needs to be undertaken to assess the range frequency intensity and intentionality of marsh disturbance events we suggest that the origin of persistent places and larger aggregation settlements in the azraq basin may have b

copper bearing encrustations a tool for age dating and constraining the physical chemical regime during the late quaternary in the wadi araba southern jordan the alluvial fluvial drainage system in the wadi araba southern jordan incised into cambrian clastic sedimentary and felsic igneous rocks giving rise to a disseminated cu mn mineralization of diagenetic and epigenetic origin along the southern branch of the dead sea transform fault dstf during the late pleistocene and holocene the primary cu sulfides were replaced by secondary minerals giving rise to hypogene to supergene encrustations bearing cu silicates cu carbonates cu oxychlorides and cupriferous vanadates they occur in fissures coat walls and developed even rim meniscus and blocky cements in the arenites near the surface the first generation cement has been interpreted in terms of freshwater vadose hydraulic conditions while the second generation blocky cement of chrysocolla and malachite evolved as late cement the cu si c fluid system within the wadi araba drainage system is the on shore or subaerial facies of a regressive lacustrine regime called the lake lisan stage a precursor of the present day dead sea radiocarbon dating younger than 27 740 1 570 years oxygen isotope based temperature determination hot brine related mineralization at 60 80 c climate driven mineralization at 25 30 c and thermodynamical calculations let to the subdivision of this secondary cu mineralization into four stages whose chemical and mineralogical composition was controlled by the variation of the anion complexes of silica and carbonate and the chlorine contents the acidity of the pore water positively correlates with the degree of oxidation the highest aridity and most intensive evaporation deduced from the thermodynamical calculations were achieved during stage 3 which is coeval with late lake lisan geogene processes causing cu enriched encrustations overlap with man made manganiferous slags the smelter feed has been derived mainly from cu ore which developed during late pleistocene in the region

high resolution geological record of historic earthquakes in the dead sea basin a 2000 year paleoseismic record of the dead sea area was recovered from a lacustrine sedimentary section the section is being exposed at the ze elim terrace on the shores of the dead sea due to the fast retreat of the lake the section consists of laminated detrital and chemical mainly aragonite sediments that were deposited in the holocene paleo dead sea eight layers in the section show deformed sedimentary structures and are identified as seismites their chronology was determined by radiocarbon dating on organic remains the seismite ages are well correlated with the historically documented earthquakes of 64 and 31 b c and 33 363 1212 1293 1834 and 1927 a d the few historically documented earthquakes that have no correlatives in the ze elim seismite record occurred in times of sedimentary hiatuses at this site e g 749 a d based on modern analogues and the association of similar disturbed layers with syndepositional faults the ze elim terrace seismites indicate m 5 5 earthquakes the average recurrence interval is estimated as 100 300 years and represents slip events on different faults in the dead sea area the ze elim section provides a unique opportunity to correlate two independent and extensive data sets the historical and sedimentary records this study opens the way for better understanding of spatial and temporal distribution of earthquakes along the dead sea transform and elsewhere

the origin of brines underlying lake kinneret abstract lake kinneret lk is a relatively fresh water lake situated in the dead sea rift dsr valley the pore water pw in the sediments underlying lk pelagic zone have significantly higher salinity than that of the lake the concentrations of major ion solutes cl br na k mg in pw from six 2 4 m to 5 1 m long sediment cores increase linearly with depth indicating the occurrence of saline deep seated brines the upper part of the pw column is affected by the much fresher boundary with lk water and in most cores is characterized by gradually increasing br cl and decreasing na mg k cl molar ratios which tend to stabilize at about 2 0 m below the sediment surface the stable molar ratios in the deeper pw vary spatially and are supposed to represent the ratios in the deep underlying brines at each site when plotted as na cl vs br cl the stable ratios of the northern and central part of the lake fall close to a straight line which characterizes many of the brines in the dsr valley however the respective ratios in the southern part of the lake fall markedly off the dsr line moreover na cl and k cl molar ratios in the south are significantly higher than in the central and northern parts 37 cl measured in present lk water is ca 0 0 along the pw column at the lake center 37 cl is becoming more positive with depth reaching values of about 0 5 to 0 6 at 3 m depth even more positive values 0 7 to 0 8 are detected further north in pw from deeper sediment layers in contrast in pw from the southeastern part of the lake 37 cl is becoming more negative with depth 1 0 at 2 6 m it is suggested that these isotopic differences are also indicative of spatial variability in the pw brine sources 18 o and d values in the pw of all 3 m long cores are similar and resemble the respective levels in lk the source of h 2 o in 3 m deep bed sediments is claimed to be the overlying lake water and therefore water isotopes do not provide a clue regarding the original water isotopic composition in the underlying brines pw from the southeast with higher k cl and na cl but lower concentrations of these solutes suggest leaching by meteoric water of sub surface halite and post halite salt formations while the more saline pw from the northern and central parts that have lower k cl and na cl and higher br cl are similar to dsr brines and represent underlying residual brines

late holocene lake levels of the dead sea this work presents a high resolution lake level record of the late holocene dead sea a hypersaline terminal lake whose drainage basin encompasses both mediterranean and hyperarid climatic zones the lake level curve reflects the regional hydrologic variations in the drainage basin which in turn represent the levant paleoclimates the curve is based on 46 radiocarbon ages of organic remains from well exposed sedimentary sequences along the dead sea shores these sequences record fluvial and lacustrine depositional environments the paleolakeshores are marked by shore ridges coarse sand units and aragonite crusts in the modern dead sea such features indicate the exact elevation of the shore the late holocene dead sea level fluctuated within the range of 390 to 415 m below sea level mbsl for most of the time the lake was below the topographic sill 402 mbsl separating the northern and southern basins of the dead sea and was confined to the deep northern basin nevertheless short term rises in the late holocene dead sea level caused the flooding of the shallow and flat southern basin highstands occurred in the second and first centuries b c and the fourth century a d during the roman and early byzan tine periods respectively in the eleventh and twelfth centuries a d during the crusader period and at the end of the nineteenth century a d the rises mark a significant change in the annual rainfall in the region which likely exceeded the instrumentally measured modern average the curve also indicates drastic drops that exposed the sedimentary sequences to erosion the oldest and probably deepest drop in the lake level culminated during the fifteenth and fourteenth centuries b c after a retreat from a higher lake stand the longest lowstand occurred after the byzantine period and continued at least until the ninth century a d this arid period coincided with the invasion of moslem arab tribes into the area during the seventh century a d the dramatic fall of the dead sea level during the twentieth century is primarily artificial and has been caused by the diversion of runoff water for the drainage basin but the magnitude is not considered exceptional for the late holocene although the past drops in the lake never exceeded the modern artificial drop rates they do represent extreme arid conditions that occurred frequently over the past several thousand years

differential exhumation at eastern margin of the tibetan plateau from apatite fission track thermochronology abstract new apatite fission track aft ages from mesozoic sediments in the sichuan basin combined with previous fission track data demonstrate differential uplift and exhumation across the basin particularly significant change in exhumation at least 2000 m was found across the huaying mts modeled temperature time histories and the boomerang plot of aft dataset across the basin suggest rapid cooling and exhumation events during 120 80 ma and at 20 10 ma they reflect the start of the basin scale differential uplift and exhumation which effected the eastern growth of tibetan plateau in particular nested old age center separated by huaying mts was found in the center to northwest part of the sichuan basin a simplified one dimensional steady state solution model was developed to calculate the mean exhumation rate which is 0 05 0 2 mm yr in most parts of the basin it suggests a slow exhumation across much of the basin the regional pattern of aft age length and erosion rate supports a progressive change from the nested old age center towards the southwest this pattern supports the idea of a prolonged steady state uplift and exhumation process across the basin controlled by cratonic basin structure the eastern growth of the tibetan plateau has exerted a significant effect on the rapid exhumation of the southwestern part of the sichuan basin but not on all of the basin during the late cenozoic

a new dead sea pollen record reveals the last glacial paleoenvironment of the southern levant abstract the southern levant is a key region for studying vegetation developments in relation to climate dynamics and hominin migration processes in the past due to the sensitivity of the vegetation to climate variations and the long history of different anthropogenic occupation phases however paleoenvironmental conditions in the southern levant during the late pleistocene were still insufficiently understood therefore we investigated the vegetation and fire history of the dead sea region during the last glacial period we present a new palynological study conducted on sediments of lake lisan the last glacial precursor of the dead sea the sediments were recovered from the center of the modern dead sea within an icdp campaign the palynological results suggest that irano turanian steppe and saharo arabian desert vegetation prevailed in the dead sea region during the investigated period ca 88 000 14 000 years bp nevertheless mediterranean woodland elements significantly contributed to the vegetation composition suggesting moderate amounts of available water for plants the early last glacial was characterized by dynamic climate conditions with pronounced dry phases and high but unstable fire activity anatomically modern humans entered the southern levant during a climatically stable phase late mis 4 mis 3 with diverse habitats constant moisture availability and low fire activity mis 2 was the coldest phase of the investigated timeframe causing changes in woodland composition and a widespread occurrence of steppe we used a biome modeling approach to assess regional vegetation patterns under changing climate conditions and to evaluate different climate scenarios for the last glacial levant the study provides new insights into the environmental responses of the dead sea region to climate variations through time it contributes towards our understanding of the paleoenvironmental conditions in the southern levant which functioned as an important corridor for human migration processes

composite projectiles and hafting technologies at ohalo ii 23 ka israel analyses of impact fractures morphometric characteristics and adhesive remains on microlithic tools abstract this study focuses on the correlation between the production of backed microliths in the levant during the late upper palaeolithic and their use as side elements of composite projectile weapons the investigation is based on assemblage sample of microliths from ohalo ii a 23 000 years old submerged campsite and involves analyses of diagnostic impact fractures location of adhesive remains and morpho metric characteristics of the tools two distinct adhesive materials have been also analyzed and the preliminary results indicate the use of both calcareous and organic substances the use of backed microliths as side elements of composite projectiles has been followed for scalene triangles a microlithic type unknown from the earlier upper palaeolithic in the levant the reconstruction of their use has been established based upon all the three evidence lines i e patterns of impact fractures as well as the location of adhesive remains and the morpho metric characteristics of the microliths the results of the study show an upper palaeolithic epipalaeolithic continuity in the approach to the design of hunting weapons and hafting technologies it is also suggested that the origins of composite projectiles in the levant may be found in the earlier phases of the upper palaeolithic

geomorphological response of the lower jordan river basin to active tectonics of the dead sea transform abstract the lower jordan river ljr basin has been shaped on an active tectonic segment of the dead sea transform dst the jordan valley fault jvf which remains relatively unexplored due to its rough terrain conditions hyper arid climate and location along a political border where minefields are common the ability to detect the morphology of the valley surface by remote sensing methods provides an opportunity to follow the complex tectonic structure of the ljr basin and the spatial and temporal geomorphic processes that have shaped the basin since its exposure in the early holocene after the desiccation of lake lisan 14 5 ky bp in this study we use gis analyses and image processing to explore the relation between the geomorphology of the ljr basin and the active tectonics of the jvf the morphometric fluvial parameters of the basin are interpreted in relation to mapped faults geophysical gravity interpolation and seismic data we introduce morphometric gravity relations that show an increasing trend of the morphometric parameters standard deviation std as a function of the gravity anomaly increase which are consistent with stream power formulation studies and seismic measurements our results show that the active tectonics of the jvf is concentrated towards the basin s center and the dead sea fault location and that at the borders of the gravity highs sinuosity slope and width changes together with recent seismic activity all suggest on tectonic uplifting and active faulting in those areas

mobilization of fine detritus to the dead sea basin during the late glacial and early holocene abstract the mineralogical grain size and geochemical properties e g nd and sr isotopes mg al ratios of fine detritus that accumulated in the dead sea during the late glacial to early holocene time 22 7 ka are used to identify its sources and modes of transport and to reconstruct the hydroclimate conditions in the dead sea watershed samples were retrieved from the dsddp 5017 1a core that was drilled in the deep floor of the lake and from various exposures of surface cover in the lake s watershed the data show that during most of the late glacial detrital particles were either directly blown mostly from the north sahara desert or were washed from the surface cover loessial soils of the north negev desert and judea desert this picture changed during the end of the last glacial to the early holocene 14 7 ka when the fine detritus showed evidence for contribution from surface cover that contained basaltic soils the contribution of basaltic soils to the fine detritus inventory of the dead sea and to terraces in the jordan valley indicates a period of intense erosion in the northern highlands of the dead sea watershed at an interval that partly coincides with sapropel s1 in contrast during the last interglacial sapropel s5 fine detritus was mostly mobilized to the lake from southern and eastern region of the watershed the formation and accumulation of terraces from this basaltic derived material could be an important factor in the establishment of early agriculture settlements in the jordan valley

north atlantic influence on 19th 20th century rainfall in the dead sea watershed teleconnections with the sahel and implication for holocene climate fluctuations abstract the importance of understanding processes that govern the hydroclimate of the mediterranean basin is highlighted by the projected significant drying of the region in response to the increase in greenhouse gas concentrations here we study the long term hydroclimatic variability of the central levant region situated in the eastern boundary of the basin as reveled by instrumental observations and the holocene record of dead sea level variations observations of 19th and 20th century precipitation in the dead sea watershed region display a multidecadal anti phase relationship to north atlantic natl sea surface temperature sst variability such that when the natl is relatively cold jerusalem experiences higher than normal precipitation and vice versa this association is underlined by a negative correlation to precipitation in the sub saharan sahel and a positive correlation to precipitation in western north america areas that are also affected by multidecadal natl sst variability these observations are consistent with a broad range of holocene hydroclimatic fluctuations from the epochal to the millennial and centennial time scales as displayed by the dead sea lake level by lake levels in the sahel and by direct and indirect proxy indicators of natl ssts on the epochal time scale the gradual cooling of natl ssts throughout the holocene in response to precession driven reduction of summer insolation is associated with previously well studied wet to dry transition in the sahel and with a general increase in dead sea lake levels from low stands after the younger dryas to higher stands in the mid to late holocene on the millennial and centennial time scales there is also evidence for an anti phase relationship between holocene variations in the dead sea and sahelian lake levels and with proxy indicators of natl ssts however the records are punctuated by abrupt lake level drops which appear to be in phase and which occur during previously documented abrupt major cooling events in the northern hemisphere we propose that the mechanisms by which natl ssts affect precipitation in the central levant is related to the tendency for high low pressure anomalies to persist over the eastern north atlantic western mediterranean region when the basin is cold warm this in turn affects the likelihood of cold air outbreaks and cyclogenesis in the eastern mediterranean and consequently rainfall in the central levant region depending on its phase this natural mechanism can alleviate or exacerbate the anthropogenic impact on the regions hydroclimatic future

archaeology history and geology of the a d 749 earthquake dead sea transform historical records of earthquakes can contribute significantly to understanding active faulting and seismic hazards however pre twentieth century historians were unaware of the association of earthquakes and fault ruptures consequently historical texts usually report the time and damage caused by earthquakes but not the associated faults conversely observed fault ruptures are often difficult to date in order to overcome these difficulties we have analyzed archaeological and sedimentological observations in recent excavations in the ancient city of tiberias and have combined them with interpretation of historical accounts tiberias was founded in a d 19 by king herod on the western shore of the sea of galilee kinneret herod9s stadium exposed in these excavations for the first time was damaged by boulder bearing flash floods and by an earthquake later buildings dated as late as the early eighth century are all covered by alluvium and lake deposits they are also damaged and offset by normal faults whereas buildings from the late eighth century are intact we therefore attribute the damage to the earthquake of 18 january 749 the paleoseismic observations are in good agreement with the distribution of damage on the basis of historical records both data sets indicate a 100 km long rupture segment between the kinneret and the dead sea pull apart basins demonstrating that it is capable of generating m 7 earthquakes

evidence for local shifting of the main fault and changes in the structural setting kinarot basin dead sea transform two new high resolution seismic reflection profiles from the kinarot valley dead sea rift analyzed with older conventional oil exploration profiles throw light on the quaternary evolution of the african arabian transform type plate boundary in the area the present en echelon main faults of the dead sea transform are observed in the seismic data as wide zones of deformation rather than as distinct fault planes a similar zone of deformation is observed in the center of the kinarot basin and may be associated with an extinct trace of the main fault the zemah structure previously mapped and drilled is shown by the new data to be an inactive anticline compression within the basin is suggested as being the result of motion along the now inactive main fault observed in the center of the basin compression and shortening started some 2 m y ago and ended late in the quaternary as a result of changes in the geometry of the transform at present the kinarot basin is subsiding

the chemical character of fluids forming diagenetic illite in the southern appalachian basin diagenetic illite mixed layer illite smectite i s from ordovician and devonian potassium bentonite k bentonite and shales was studied in the proximal southern appalachian basin alabama through virginia to understand in more detail the timing of illite formation as well as attempt to describe the chemistry of the fluids that formed illite during the alleghanian orogeny through combined k rb and oxygen isotope analyses the clay fraction of the k bentonites is composed predominantly of illite smectite i s and chlorite most i s exhibited kalkberg order iisi with 85 illite layers the k ar dates of i s from ordovician k bentonites and devonian k bentonites mostly range from 260 310 ma and indicate i s formed during the alleghanian orogeny internally concordant dates and similar percentages of illite layers of i s are measured from several samples collected within a thick 1 m ordovician k bentonite at fort payne alabama the oxygen isotopic values 1 8 o of i s range from 18 23 smow at lowest levels of thermal maturity and burial as seen by conodont alteration index values cai of 1 5 2 0 the range in 1 8 o values of water in equilibrium with i s is 2 5 3 5 at higher thermal maturity cai 2 5 4 5 the 1 8 o of water in equilibrium with i s is from 4 5 to 12 the 1 8 o analyses are mostly consistent with i s having formed in the presence of orogenic i e saline waters the mean k rb of the appalachian illites from this study is 325 n 20 this mean k rb is also consistent with the formation of diagenetic i s in the presence of a saline fluids having higher k activities than meteoric waters the combined data indicate these diagenetic illites in k bentonites formed from saline orogenic waters during the alleghanian orogeny along the valley and ridge province in the southern appalachian basin although the data rule out formation of diagenetic illite in the presence of meteoric water or long term reaction with connate formation waters the combined data cannot distinguish the source and the mechanism tectonic push or flush from tectonic highlands for the movement of saline fluids in the appalachian basin

quaternary tectonic evolution of the northern gulf of elat aqaba along the dead sea transform the northern gulf of elat aqaba is located in the transition between the deep marine basins of the gulf and the shallow onland basins of the arava valley interpretation of 500 km of high resolution seismic reflection data collected across the northern shelf reveals the tectonic structure and evolution of this transition six nne trending faults and one e w trending transverse fault are mapped slip rates are calculated based on measured offsets and age determination based on a radiocarbon calibrated sedimentation rate and a quaternary age model the most active fault is the evrona fault that absorbs most of the left lateral slip within the basin with an average sinistral slip rate of 0 7 0 3 mm yr through the late pleistocene and 2 3 3 4 mm yr during the holocene two intrabasin faults east of the evrona fault that have been inactive for the last several tens of thousands of years were mapped and motion from these faults has likely transferred to the evrona fault the basin is flanked on the west by the elat fault and on the east by the aqaba fault both faults are marked by large bathymetric escarpments based on displaced seismic reflectors we calculate a holocene vertical slip rate of 1 0 0 2 and 0 4 0 1 mm yr for the elat and aqaba faults respectively the geometry slip rates and slip history of the northern gulf of elat aqaba faults show that during the late pleistocene several intrabasin faults became dominant across the basin but that during the holocene the evrona fault accommodates most of the strike slip

coseismic growth of sedimentary basins along the yammouneh strike slip fault lebanon summary the left lateral yammouneh fault yf is the main active branch of the dead sea transform fault dstf within the lebanese restraining bend despite the overall transpressional setting a series of sedimentary basins have developed along the trace of the yf consequently palaeoseismic studies within these basins provide an opportunity to study the processes of coseismic growth of the basins as well as elucidate earthquake behaviour of the fault in general geodetic measurements of contemporary fault slip within the lebanese restraining bend indicate that the yf accommodates most of the expected left lateral strike slip motion despite the apparent lack of present day seismicity we studied the yf using combined investigations of remote imagery geomorphology and palaeoseismology the active fault trace along a 51 km strip was delineated as relatively young surface ruptures and fault scarps that affect holocene deposits with intermittent offset geomorphic markers seven closed basins that occur along strike of the yf were found to be related to faulting with at least three of them displaying evident pull apart settings we concentrated our work on the rhombohedral yammouneh basin an actively evolving example of pull apart basins which is presently obliquely cut by the active fault with an apparently young age of 1 4 0 3 myr 3 d correlation and analysis of palaeoseismic investigations exposed a composite shear zone with a total subsidence that exceeds 1 6 m over the past 4000 4400 yr stratigraphic and geochronological constraints suggest the occurrences of at least five large faulting events during that period by correlating the stratigraphy and ages of this trench with a previously published study located nearby a combined palaeoseismic history for the past five events is constructed this suggests a mean recurrence period of 1020 1175 yr for large earthquakes along this section of the yf our results suggest a subsidence rate due to faulting of about 0 36 0 40 mm yr 1 within the yammouneh pull apart basin the geometrical relationship between the active fault trace and the older fault traces suggests that the basin may have evolved in a two stage process in which the original releasing fault bend developed a cross cutting fault accommodating most of the subsequent strike slip displacement the role of the yf in controlling basin evolution is further supported by the correspondence of the active fault with the boundary of the present depocentre our results highlight the interrelation between active strike slip faulting and the coseismic incremental evolution of fault related sedimentary basins which may provide a conceptual model with broader implications on analogous tectonic systems worldwide

radiocarbon dating of ohalo ii archaeological and methodological implications abstract charcoal samples from the early epipalaeolithic submerged fisher hunter gatherers site of ohalo ii have been dated by three laboratories the samples derive from huts hearths a grave and a stone installation twenty five date range between 17 500 21 050 bp and average c 19 400 bp the thickness of deposits the perishable building material of the huts the spatial organization of the camp and its rapid cover by sand and water suggest several occupational episodes lasting not more than tens of years together the discrepancy between the range of 14 c dates and the real length of occupation are due to the statistical limitations of the dating method

the late quaternary limnological history of lake kinneret sea of galilee israel the freshwater lake kinneret sea of galilee and the hypersaline dead sea are remnant lakes evolved from ancient water bodies that filled the tectonic depressions along the dead sea transform dst during the neogene quartenary periods we reconstructed the limnological history level and composition of lake kinneret during the past 40 000 years and compared it with the history of the contemporaneous lake lisan from the aspect of the regional and global climate history the lake level reconstruction was achieved through a chronological and sedimentological investigation of exposed sedimentary sections in the kinnarot basin trenches and cores drilled at the ohalo ii archeological site shoreline chronology was established by radiocarbon dating of organic remains and of melanopsis shells the major changes in lake kinneret level were synchronous with those of the southern lake lisan both lakes dropped significantly 42 000 30 000 23 800 and 13 000 yr ago and rose 39 000 26 000 5000 and 1600 yr ago between 26 000 and 24 000 yr ago the lakes merged into a unified water body and lake level achieved its maximum stand of 170 m below mean sea level m bsl nevertheless the fresh and saline water properties of lake kinneret and lake lisan respectively have been preserved throughout the 40 000 years studied calcium carbonate was always deposited as calcite in lake kinneret and as aragonite in lake lisan dead sea indicating that the dead sea brine which supports aragonite production never reached or affected lake kinneret even during the period of lake high stand and convergence the synchronous level fluctuation of lakes kinneret lisan and the holocene dead sea is consistent with the dominance of the atlantic mediterranean rain system on the catchment of the basin and the regional hydrology the major drops in lake kinneret lisan levels coincide with the timing of cold spells in the north atlantic that caused a shut down of rains in the east mediterranean and the lakes drainage area d 2004 university of washington all rights reserved

strontium isotopic chemical and sedimentological evidence for the evolution of lake lisan and the dead sea precise strontium isotope ratios combined with chemical analyses and sedimentological information are used to monitor the water sources and the evolution of the dead sea and its late pleistocene precursor lake lisan 70 18 kyr b p the materials analyzed include bulk aragonite water leached soluble salts and residual aragonite and gypsum from the lisan formation in the perazim valley near the sw shore of the dead sea the residual aragonite and the associated soluble salts display systematic fluctuations in 17sr86sr ratios between 0 70803 and 0 70806 and from 0 70805 to 0 70807 respectively in individual soluble salt residual aragonite pairs the soluble salt displays a higher 87sr86sr ratio gypsum samples yield 17sr86sr ratios similar to the soluble salts from adjacent layers in the section this shows that in individual samples the source of sr in aragonite was distinct from that in soluble salts and the gypsum the sterility of the lisan sediments their strictly nonbioturbated fine lamination and their high content of chloride salts indicate that lake lisan was a saline or even hypersaline water body in the absence of alternative sources of hco3 and s042 the abundance of primary aragonite and gypsum in the lisan column reflects an import of very large volumes of freshwater into the otherwise saline lake resulting in a density stratification of this water body the history of the upper water layer and that of the lower brine is reflected in the chemical and strontium isotope composition of the aragonite and in that of the associated soluble salts and in the gypsum samples respectively whereas the bicarbonate and much of the ca2 required for aragonite crystallization were supplied by the freshwater the complementary ca2 and sr 2 were added by the lower brine the upper water layer of lake lisan acted as a so42 capacitor during the lake s rise periods it was removed therefrom as prominent gypsum beds upon climatic induced drier period mixing or even complete overturn of the lake the evolution of lake lisan took place between two distinct modes the first was characterized by an extensive supply of freshwater and resulted in a rise of the lake s level a density layered structure and precipitation of aragonite the second mode was marked by a diminishing freshwater input resulting in mixing or complete overturn of its water and precipitation of gypsum these two modes reflect the climatic evolution of the region in the late pleistocene which fluctuated between drier and wetter periods the transition to the holocene is accompanied by the dry up of lake lisan and its contraction to the present dead sea

evidence from lake lisan of solar influence on decadal to centennial scale climate variability during marine oxygen isotope stage 2 documentation of short term climate variability during the glacial period has been limited by the availability of well dated high resolution archives here we present a paleoclimate reconstruction from varved lacustrine sediments of lake lisan dead sea rift for ca 26 2 17 7 calendar ka the age is based on a floating varve chronology anchored to radiometric dates our reconstruction indicates that small ice rafting events a b c and d as well as heinrich events in the north atlantic are associated with the eastern mediterranean arid intervals study of seasonal sublaminae yields evidence of several additional decadal to century scale arid events that correlate with cooler temperatures at higher latitudes analyses in the frequency domain indicate the presence of periodicities centered at 1500 yr 500 yr 192 yr 139 yr 90 yr and 50 60 yr suggesting a solar forcing on climate

calibration of the 14c time scale to 40 ka by 234u 230th dating of lake lisan sediments last glacial dead sea a new comparison of 14c dates with 234u 230th ages is presented of aragonites from lake lisan the last glacial dead sea between 20 52 cal ka bp the lisan data are coincident with the coral based 14c calendar age calibration through the continuous portion of the curve to 23 5 cal ka bp and with the additional checkpoints at 30 and 40 cal ka bp the agreement with the corals provides evidence for the accuracy of the u th and 14c ages and indicates that lisan aragonites can potentially be used to generate a nearly continuous record of the atmospheric 14c variations through this crucial time interval the lisan data are compared with other records older than 25 cal ka bp from lake suigetsu japan north atlantic foraminifera south african cave deposits and tufa from spain over some age intervals the records show broad agreement over other intervals they diverge all agree that 14c ages were 2 5 0 5 ka younger than calendar ages between 20 32 cal ka bp for ages 32 cal ka bp the lake suigetsu data indicate small differences between 14c ages and calendar ages of less than 1 5 ka the other records broadly agree that 14c ages are too young by 3 1 ka from 32 39 cal ka bp at 40 cal ka bp the foraminifera show equal 14c and calendar ages while the corals lisan aragonites and the spanish tufa indicate a large age difference of 4 5 ka a recent paleomagnetic study of the lisan formation indicates that the high calendar 14c age difference at 40 cal ka bp may be associated with the laschamp paleomagnetic excursion

distinct relict fringing reefs in the northern shelf of the gulf of elat aqaba markers of quaternary eustatic and climatic episodes quaternary reef development and demise have been shown to correspond to worldwide sea level fluctuations and related environmental changes yet the mechanisms and rates affecting this relationship are not well resolved a set of high resolution seismic reflection and multibeam bathymetric data were interpreted six distinct systems of relict fringing reefs embedded within the sedimentary cover of the northern shelf of the gulf of elat aqaba were identified the two uppermost relict fringing reefs are also exposed on the sea floor in water depths of ca 20 m and ca 60 m along the north western corner of the northern gulf of elat aqaba and sub parallel to the current northern coast respectively two other relict fringing reefs are laterally correlated to each of the last two transgressive cycles and are inferred to have formed during decelerations in sea level rise during the last two deglaciations these reefs and the units to which they are laterally correlated portray a repeating stratigraphic pattern of reef development during deposition of seismically homogeneous sediment and an ensuing demise during deposition of heterogeneous sediment correlation of the reef stratigraphy with rates of late quaternary sea level rise and a sediment accumulation rate from one shelf core provide age estimations for the seismic stratigraphy two phases of fringing reef generation occurred during the last deglaciation since ca 18 ka the older reef probably developed between 12 8 ka and 11 5 ka at ca 60 m below present sea level and the younger reef after 8 4 to 8 0 ka at ca 20 m below present sea level these last two phases of reef generation are separated by a lobate seismic unit that is interpreted as fluvial deltaic deposits that backstepped across the shelf during the early holocene transgression results suggest that fringing reefs evolved along the northern shelf of the gulf of elat aqaba only during relative decelerations in sea level rise contemporaneous with low input of terrigenous sediment and probably during a period of aridity at present no fringing reef grows along the northern coast of the gulf of elat aqaba suggesting that these relatively arid periods may have been drier than recent the pattern of slowdown in sea level rise contemporaneous with conditions of increased aridity seems to have repeated during the last two sea level rises approximately at the same sea levels suggesting a common mechanism of short millennium scale phases of eustatic and climatic alteration during deglaciations

controlling factors on a paleo lake oxygen isotope record yammouneh lebanon since the last glacial maximum abstract late quaternary paleoclimatic changes in the levant are difficult to extract from carbonate oxygen isotope records partly because the factors controlling the terrestrial 18 o signals are not fully understood in this region characterized by sharp climatic gradients here we address this purpose by presenting the first 14 c dated isotope record from the northern levant the record is based on oxygen isotopes from ostracod shells from lacustrine palustrine deposits accumulated in a small karstic hydrologically open basin yammouneh located on the eastern flank of mount lebanon we have first constructed a composite isotopic record obtained from three different ostracod taxa this yields an oxygen isotope record of ostracods ost related to the most widespread species ilyocypris inermis and converted to 18 o values coeval with calcite precipitated in equilibrium c with the lake water l as with other records from the mediterranean region the yammouneh profile shows maximum and minimum c values during the lgm and the early holocene respectively and a slight late holocene increase in order to discuss the potential causes of the observed 18 o values fluctuations e g changes in the isotopic composition of the moisture source temperature precipitation minus evaporation p e balance or atmospheric circulation we tentatively reconstruct the lake water isotope composition by correcting the c values for lake water temperature using regional paleotemperature estimates inferred l values were then corrected for the isotopic composition of the eastern mediterranean sea surface water the moisture source derived from planktonic foraminifera 18 o values corrected for alkenone based sea surface temperature our study suggests that holocene l fluctuations are primarily linked to changes in the sea surface water composition source effect amplified by enhanced inland rainfall during the early holocene during the lgm low l values at yammouneh are likely due to the ground temperature effect on the rainfall isotope composition possibly associated with a steeper altitudinal thermal gradient inland and with changes in air mass trajectories over the mediterranean sea

primary carbonates and ca chloride brines as monitors of a paleo hydrological regime in the dead sea basin abstract lakes samra lisan and the dead sea occupied the dead sea basin during the last interglacial 140 75 ka bp last glacial 70 14 ka bp and holocene periods respectively the age of lake lisan and samra was determined by u th dating of primary aragonites comprising parts of the lacustrine sedimentary sequences the lakes have periodically deposited sequences of layered calcitic marls lake samra or laminated primary aragonite lake lisan the deposition of aragonite as the primary carbonate phase reflects the contribution of the incoming freshwater loaded with bi carbonate and high mg ca chloride brine that originated from the subsurface vicinity of the dead sea basin deposition of calcitic marls suggests a minor effect of the brines the ca chloride subsurface brine has been migrating in and out of the wall rocks of the dead sea basin reflecting the regional hydrological conditions during most of the last glacial period and during the late holocene sufficient precipitation above the judea mountains pushed the subsurface ca chloride brines into the lakes causing the deposition of aragonite during the last interglacial period the rain that precipitated above the judea mountains was insufficient to induce brine flow toward lake samra it appears that sporadic floods provided calcium bicarbonate and detritus to produce the samra calcitic marls travertines deposited at the samra lisan boundary indicate the early stage in the resumption of groundwater springs activity that led to the resurgence of ca chloride brine and rise of lake lisan similar variations in the regional rain precipitation and hydrological activity probably characterized the long term geochemical evolution of pleistocene lacustrine water bodies in the dead sea basin enabling the use of the carbonates as paleo hydrological monitors

lake levels and sequence stratigraphy of lake lisan the late pleistocene precursor of the dead sea lake lisan the late pleistocene precursor of the dead sea existed from 70 000 to 15 000 yr b p it evolved through frequent water level fluctuations which reflected the regional hydrological and climatic conditions we determined the water level of the lake for the time interval 55 000 15 000 cal yr b p by mapping offshore nearshore and fan delta sediments by application of sequence stratigraphy methods and by dating with radiocarbon and u series methods during the studied time interval the lake level fluctuated between 340 and 160 m below mean sea level msl between 55 000 and 30 000 cal yr b p the lake evolved through short term fluctuations around 280 290 m below msl punctuated at 48 000 43 000 cal yr b p by a drop event to at least 340 m below msl at 27 000 cal yr b p the lake began to rise sharply reaching its maximum elevation of about 164 m below msl between 26 000 and 23 000 cal yr b p then it began dropping and reached 300 m below msl at 15 000 cal yr b p during the holocene the lake corresponding to the present dead sea stabilized at ca 400 m below msl with minor fluctuations the hypsometric curve of the basin indicates that large changes in lake area are expected at above 403 and 385 m below msl at these elevations the lake level is buffered lake lisan was always higher than 380 m below msl indicating a significantly large water contribution to the basin the long and repetitious periods of stabilization at 280 290 m below msl during lake lisan time indicate hydrological control combined with the existence of a physical sill at this elevation crossing this sill could not have been achieved without a dramatic increase in the total water input to the lake as occurred during the fast and intense lake rise from 280 to 160 m below msl at 27 000 cal yr b p

seven ambiguities in the mediterranean palaeoenvironmental narrative abstract a review of seven outstanding issues on mediterranean palaeoenvironments is presented these are related to the dominant orbital pacing of climate variability the length of the interglacial vegetation succession the influence of the african summer monsoon the seasonality of precipitation during boreal insolation maxima the moisture balance during glacial maxima and the appearance of the mediterranean type climate rhythm and evolution of mediterranean sclerophyllous plants what emerges is that 1 marine 18oplanktonic and sst records show that precession has been a fundamental tempo of mediterranean climate change representing both a low latitude signal runoff from north africa and the direct influence of insolation at mediterranean latitudes but high latitude glacial effects 41 kyr and 100 kyr cycles became superimposed after 2 8 ma sapropel and dust deposition patterns in marine cores reveal that obliquity also has an effect on mediterranean climate through dry wet oscillations which are independent of glacial interglacial variability 2 the temperate part of interglacial vegetation succession has a duration of approximately half a precession cycle this persisted during the interval of obliquity dominated glacial cycles 2 8 1 ma with distinct forest successions following the precessional cycles however these are not always separated by an open vegetation phase because of minimal ice growth producing an impression of a prolonged interglacial forest interval 3 the effect of an enhanced african monsoon during summer insolation maxima has been mainly indirect in terms of nile discharge and runoff along the north african coast leading to increased freshwater input into the mediterranean sea reduced deep water ventilation and sapropel deposition 4 the notion of an accentuated summer rain regime in the northern mediterranean borderlands also contributing to a freshening of the mediterranean sea during boreal insolation maxima is not supported by the available evidence which suggests increased summer aridity 5 recent improvements in chronological precision and data resolution point to an increase in aridity and decreased temperatures during the last glacial maximum 21 2 ka but suggest an increase in effective moisture during the immediately preceding interval of 24 27 ka 6 the mediterranean type climate is not exclusively a post 3 6 ma phenomenon but may have appeared intermittently during the course of the tertiary or before 7 if that is the case then the paradigm that the sclerophyllous evergreen habit represents a pre adaptation to summer drought may need re evaluation

reconstructing low levels of lake lisan by correlating fan delta and lacustrine deposits abstract reconstruction of paleo shorelines of lake lisan the late pleistocene precursor of the dead sea is based on sequence stratigraphy of fan delta and lacustrine deposits that are exposed at the perazim valley southwest of the dead sea the shoreline sediments are physically correlated with lacustrine aragonites their ages are determined by u series dating to establish a lake level curve for the time interval between 55 and 35 kyr during most of this period lake lisan was at a relatively low level which fluctuated between 280 and 290 m below sea level m bsl the minimum lake stand 330 m bsl was reached at 47 kyr and lasted for 3 4 kyr this episode is marked by a depositional hiatus in the section and formation of an erosional channel the studied period correlates with the global marine isotope stage 3 the low stand of lake lisan during most of this period indicates relative dry climatic conditions in the region

late holocene climates of the near east deduced from dead sea level variations and modern regional winter rainfall the dead sea is a terminal lake of one of the largest hydrological systems in the levant and may thus be viewed as a large rain gauge for the region variations of its level are indicative of the climate variations in the region here we present the decadal to centennialresolution holocene lake level curve of the dead sea then we determine the regional hydroclimatology that affected level variations to achieve this goal we compare modern natural lake level variations and instrumental rainfall records and quantify the hydrology relative to lake level rise fall or stability to quantify that relationship under natural conditions rainfall data pre dating the artificial dead sea level drop since the 1960s are used in this respect jerusalem station offers the longest uninterrupted pre 1960s rainfall record and jerusalem rains serve as an adequate proxy for the dead sea headwaters rainfall principal component analysis indicates that temporal variations of annual precipitation in all stations in israel north of the current 200 mm yr 1 average isohyet during 1940 1990 are largely synchronous and in phase 70 of the total variance explained by pc1 this station also represents well northern jordan and the area all the way to beirut lebanon especially during extreme drought and wet spells we a determine the modern and propose the past regional hydrology and eastern mediterranean em climatology that affected the severity and length of droughts wet spells associated with multiyear episodes of dead sea level falls rises and b determine that em cyclone tracks were different in average number and latitude in wet and dry years in jerusalem the mean composite sea level pressure and 500 mb height anomalies indicate that the potential causes for wet and dry episodes span the entire em and are rooted in the larger scale northern hemisphere atmospheric circulation we also identified remarkably close association within radiocarbon resolution between climatic changes in the levant reflected by level changes and culture shifts in this region

orbital scale environmental and climatic changes recorded in a new 200 000 year long multiproxy sedimentary record from padul southern iberian peninsula abstract padul is one of the few wetland sites in southern europe and the mediterranean region that exhibits an unusually large temporal span 100 kyr and continuous quaternary sedimentary record previous core based studies from padul yielded paleoecological datasets i e pollen and organic geochemistry but with a poor age control that resulted in rather arbitrary climate inferences therefore precise age control and a multidisciplinary approach is necessary to understand long term regional environmental and climate change and the associated local response of the padul wetland environment here we present a new long sediment record padul 15 05 from this wetland in the southern iberian peninsula with the aim of improving the age control of the sedimentary sequence and carrying out up to date high resolution multiproxy analyses in this study the age control is based on 61 ams radiocarbon dates for the last ca 50 kyr bp and on the extent of amino acid racemization aar in mollusc shells extending back 118 kyr bp no numerical ages are available for the bottom part of the core but the sediment accumulation rates sar and the cyclostratigraphic analysis of the multiproxy data suggest that the core preserves a continuous record of the last 197 kyr from late mis 7 to present with millennial scale time resolution sedimentological lithology magnetic susceptibility xrd color geochemical xrf toc c n carbonate content and paleontological pollen charophytes gastropods data show co varying cyclical paleoenvironmental changes linked to orbital scale climatic variability silicon magnetic susceptibility ms and total organic carbon toc data show periodicities between 26 2 19 6 kyr linked to insolation which is strongly dominated by precession cycles at this latitude high values of si and ms data have been related to high siliciclastic detrital input from sierra nevada range during minima in insolation due to enhanced soil weathering erosion during regional aridity and lower forest cover recorded by the arboreal pollen which could also be favored by a minor biogenic productivity in addition warm climate conditions during maxima in insolation mostly resulted in negative precipitation evapotranspiration balance and low lake levels while cold glacial and stadial periods were mainly characterized by positive precipitation evapotranspiration balance and therefore high lake levels the improved chronology of the padul sedimentary sequence along with a multiproxy study permitted us to better relate environmental and vegetation changes to climatic events and to demonstrate how both local i e lake level sedimentation and regional i e vegetation environments responded to orbital scale climate changes

the holocene climatic record of the salt caves of mount sedom israel mount sedom is a salt diapir on the southwestern shore of the dead sea which has been rising above the local base level throughout the holocene karst development within the salt body has kept pace with the rise forming subhorizontal cave passages with vertical shafts wood fragments found embedded in flood sediments that were deposited in the cave passages yielded 14c ages ranging from c 7100 to 200 bp a palaeoclimatic sequence was constructed based on parameters that include relative abundance of plant types or floral communities the elevations of the corresponding cave passages and the ratio of their width to present passage width the results were correlated to the holocene sedimentary sequence of the dead sea basin and other features associated with shifting lake levels moister climatic stages are indicated by relatively abundant wood remains by wide cave passages and by elevated outlets indicating high dead sea level arid periods are marked by a scarcity of wood remains by narrow cave pa

sedimentary geochemical and hydrological history of lake kinneret during the past 28 000 years abstract the sedimentary geochemical and hydrological history of lake kinneret sea of galilee is reconstructed for the past 28 kyrs based on three sedimentary cores drilled at the lake and a trench dug at the shore of the prehistorical ohalo ii site during the past 28 kyrs either laminated or massive fine grained sediments were deposited in the lake comprising primary calcites and fine grain detritus sr ca mg ca 87sr 86sr ratios and 18o values of live and fossil ostracod shells cyprideis torosa and primary calcites together with xrd grain size and carbonate content analyses indicate contribution of the following types of waters to the lake 1 jordan river 2 regional runoff and 3 ca chloride brines currently comprises the tiberias spa brine during the last glacial period 28 24 ka the lake rose to its highest stand of 170 m below sea level bsl expanding over the kinnarot basin and converging with the southern hypersaline lake lisan at that time waters were mainly supplied to the lake by the jordan river and regional runoff with enhanced contribution of the dead sea ca chloride brine primary calcites were precipitated from the lake s solution forming sequences of laminated sediments on the lake s floor at 24 22 ka coinciding with heinrich event h2 at the north atlantic the lake retreated below the modern level of 214 m bsl depositing mainly flood related sediments at its margins the lake slightly rose during the younger dryas and subsequently declined towards the modern level with decreasing contributions of the jordan river waters brines and regional runoff reflecting a continuous aridification of the region during the holocene

u th dating of lake lisan late pleistocene dead sea aragonite and implications for glacial east mediterranean climate change u series dating can be an effective means to obtain accurate and precise ages on quaternary carbonates however most samples require a correction for u and th in admixed detritus this complication is often addressed through generation of u th isochrons requiring analyses of several coeval samples in addition presence of water derived hydrogenous th in the carbonate can cause inaccuracies in isochron ages this study reports a high resolution u series chronology of sediments deposited by lake lisan the last glacial precursor of the dead sea the strategy employed combines multiple measurements from a few stratigraphic heights and fewer analyses from many heights in a single described and measured section the resulting chronology is based on ages at 22 heights in a 40 m thick section covering the interval of 70 14 calendar ka bp the effects of admixed detritus are evaluated using trace elements nearly pure aragonite samples indicated by very low abundances of insoluble elements such as nb and zr were found to contain hydrogenous th which causes the uncorrected u 230th age of a modern sample to be 2 5 ka nevertheless accurate ages have been obtained by correcting for the detrital and aqueous interferences the resulting ages are in stratigraphic order and their accuracy is evidenced by consistency of lisan formation u series and 14c ages with the coral based calendar radiocarbon age calibration the u th ages provide a context to unravel the limnological history of lake lisan boundaries between the lower middle and upper stratigraphic units correspond to the mis 4 3 and 3 2 transitions respectively during mis 2 and 4 the lake generally showed a stable two layer configuration and a positive fresh water balance reflected by deposition of laminated aragonite detritus dry intervals during mis 2 and 4 are indicated by thick gypsum layers and an inferred depositional hiatus which are temporally associated with heinrich events h1 at 17 ka and h6 at 65 ka respectively during mis 3 the lake level was unstable with intermittent dry periods indicated by abundant clastic layers and a significant hiatus between 43 49 ka clastic layers are associated with dansgaard oeschger events during mis 3 and indicate lake level declines during abrupt northern hemisphere warmings overall the climate of the eastern mediterranean region shows a strong linkage to the northern hemisphere climate with increasing lake size and stability during cold periods and fluctuations and dessication during warmings and heinrich events

recurrence pattern of holocene earthquakes along the dead sea transform revealed by varve counting and radiocarbon dating of lacustrine sediments abstract a high resolution holocene seismic history of the dead sea transform dst is established from laminated sedimentary cores recovered at the shores of the dead sea radiocarbon dating and annual laminae counting yield excellent agreement between disturbed sedimentary structures identified as seismites and the historical earthquake record all recent and historical strong events of the area were identified including the major earthquakes of a d 1927 1837 1212 1033 749 and 31 b c the total of 53 seismites recognized along the entire holocene profile indicate varying recurrence intervals of seismic activity between a few and 1000 years with a conspicuous minimum rate at 2100 31 b c and a noticeable maximum during the past six to eight centuries most of the epicenters of the correlated earthquakes are situated very close to the dead sea within 150 km or up to 400 km north of it along the dst between 1000 b c and a d 1063 and from a d 1600 to recent time the epicenters are all located on the northern segment of the dst whereas prior to 1000 b c and between a d 1000 and 1600 they appear to scatter along several segments of the dst we establish how the local intensity exerts a control on the formation of seismites at historically estimated intensities greater than vii all well documented earthquakes are correlated whereas at intensities smaller than vi none are matching the periods with enhanced earthquake rate along the dst correlate with those along the north anatolian fault as opposed to the intervening east anatolian fault this may indicate some elastic coupling on plate boundary scale that may also underlie escape and extrusion tectonics typical of continental collision

southward migration of rain tracks during the last glacial revealed by salinity gradient in lake lisan dead sea rift abstract the paleosalinity of the late pleistocene lake lisan during its highstand between 27 000 and 15 000 years b p is evaluated from biological data diatoms cyanobacteria fish and ostracods and chemical data sr ca and na ca ratios in authigenic aragonite the data indicate a zone of maximum salinity at the southern part of the lake in the vicinity of the present dead sea basin while most of the freshwater input to lake lisan originated from the jordan river in the north and runoff from the eastern and western parts of the drainage basin our analysis indicates a significant additional contribution from a southern freshwater source at present the contribution of the southern source to the dead sea is minimal hence it appears that in addition to the prevailing rain originating from the mediterranean an additional southern source of rain was more active during the last glacial than today this may be explained by migration of rain tracks whose moisture originated in the atlantic from the mediterranean southwards

12 000 year long record of 10 to 13 paleoearthquakes on the yammouneh fault levant fault system lebanon we present results of the first paleoseismic study of the yammouneh fault the main on land segment of the levant fault system within the lebanese restraining bend a trench was excavated in the yammouneh paleolake where the fault cuts through finely laminated sequences of marls and clays first order variations throughout this outstanding stratigraphic record appear to reflect climate change at centennial and millennial scales the lake beds are offset and deformed in a 2 m wide zone coinciding with the mapped fault trace ten to thirteen events are identified extending back more than 12 kyr reliable age bounds on seven of these events constrain the mean seismic return time to 1127 135 yr between 12 ka and 6 4 ka implying that this fault slips in infrequent but large m 7 5 earthquakes our results also provide conclusive evidence that the latest event at this site was the great a d 1202 historical earthquake and suggest that the yammouneh fault might have been the source of a less well known event circa a d 350 these findings combined with previous paleoseismic data from the zebadani valley imply that the parallel faults bounding the beqaa release strain in events with comparable recurrence intervals but significantly different magnitudes our results contribute to document the clustering of large events on the levant fault into centennial episodes such as that during the eleventh through twelfth centuries separated by millennial periods of quiescence and raise the possibility of a m 7 event occurring on the yammouneh fault in the coming century such a scenario should be taken into account in regional seismic hazard assessments and planned for accordingly

greigite detected as dominating remanence carrier in late pleistocene sediments lisan formation from lake kinneret sea of galilee israel summary a rock magnetic investigation of three sedimentary cores of lisan formation of late pleistocene age from lake kinneret sea of galilee northern israel demonstrates that the magnetization of these sediments is controlled by various degrees of a secondary chemical remanent magnetization crm carried by greigite fe3s4 this crm is superimposed on a primary detrital remanent magnetization drm that resides in ti magnetite this finding is independently confirmed by x ray diffraction xrd measurements performed on magnetic extracts of the sediments the domain state of the greigite is largely single domain behaviour sd thus dominating the magnetization therefore the magnetic record retrieve from of these sediments is not reflecting geomagnetic variations but rather chemical rock magnetic properties resulting from diagenetic processes the results of our study suggest that paleomagnetic record of greigite bearing sediments should be interpreted with caution because of the following reasons 1 geomagnetic secular variations can be biased due to large coercivity overlap between magnetite and greigite 2 alternating field af demagnetization can produce erroneous directions due to vector distortion by acquisition of a gyro remnant magnetization grm 3 estimation of relative paleointensity can be hampered by large scale variations in natural remnant magnetization nrm intensity caused by the acquisition of a secondary crm of unknown age and unknown extent superimposed on the drm the precipitation of greigite requires reducing conditions at the sediment water interface and or interstitial water associated with the presence of sulphur and iron oxides reducing conditions are typical of stratified lakes and other stratified water bodies such as the dead sea paleo lake lisan temporarily the eastern mediterranean sea the caspian sea the black sea and many other marine basins according to our findings paleomagnetic records from such environments carried dominantly by greigite therefore should be treated with care

dissolution of titanomagnetite and sulphidization in sediments from lake kinneret israel summary magnetic extracts obtained from sediment cores recovered from lake kinneret israel were subjected to comprehensive scanning electron microscope and in line energy dispersive x ray spectroscopy analyses a variety of ferrimagnetic iron oxides and iron sulphide particles were identified along with apparently non magnetic iron sulphides the majority of the iron oxides are titanomagnetites that have undergone pervasive dissolution and in many cases were only preserved as skeletal 3 d lattices of ilmenite lamellae often the spaces between the submicron ilmenite lamellae are empty also sponge like dissolution features are observed in some residual titanomagnetite grains another group of titanomagnetite grains is characterized by superficial shrinkage cracks which indicate low temperature maghemitization in some cases these cracks appear to be where dissolution started most titanomagnetites contain impurities of al mg si and mn on the order of 1 per cent chromium magnetites with minor ti mg and al content on the order of a few percent but without mn were also found chromium magnetites mostly occur as octahedra in a well preserved state which indicates that they are less prone to dissolution magnetite spherules of 40 60 m in size which were mostly hollow were only found in material collected from the outer zone of the core section that was in contact with the steel core barrel these spherules were not found in material collected from the centre of the core they are therefore interpreted as contaminants that were produced during fabrication of the steel core barrel iron sulphides are present as pyrite either as larger aggregates of cubic crystals each of up to 20 m in size or as 5 10 m framboidal aggregates consisting mostly about 0 3 m idiomorphic octahedra the cubic pyrite crystals have heterogeneous compositions pure pyrite should be non magnetic but even aggregates of up to 150 m in size were magnetically separated they probably therefore contain a magnetic core of greigite or overgrown titanomagnetite the latter possibility is supported by observations of residual titanomagnetites with individual pyrite crystals residing directly on their surfaces or filling space between ilmenite lamellae irregular aggregates of flaky submicron iron sulphides were also found which are interpreted to be greigite the greigite has a low degree of visible crystallization pyrite and or greigite grains were found inside the aggregates or in agglomerates with organic remnants together visual observations and elemental analyses provide clear evidence of pervasive dissolution of primary titanomagnetite and concurrent sulphidization of sediments from lake kinneret

activation of a small ephemeral lake in southern jordan during the last full glacial period and its paleoclimatic implications playas or ephemeral lakes are one of the most common depositional environments in arid and semiarid lands worldwide playa deposits however have mostly been avoided as paleoclimatic archives because they typically contain exceptionally low concentrations of organic material making 14 c dating difficult here we describe a technique for concentrating organic matter in sediments for radiocarbon dating and apply it to playa sediments recovered from a 2 35 m sediment core from a small playa in southern jordan based on 14 c ages of the organic concentrate fraction the playa was active from 29 to 21 ka coincident with the last major high stand of paleolake lisan and wet conditions recorded by other paleoclimatic proxies in the southernmost levant during the last full glacial period 35 20 ka the timing and spatial pattern of these records suggests that the increased moisture was likely derived from more frequent and deeper eastern mediterranean em cyclones associated with the intensification of the westerlies the presence of full glacial pluvial deposits in southern jordan 29 n and the lack of similarly aged deposits in the northern arabian peninsula to the south suggests that the southerly limit of the incursion of em cyclones during last full glacial period was 28 n