late quaternary geological history of the dead sea area israel abstract a 34 5 m borehole which was drilled near the dead sea coast altitude 394 m in the southern part of the fan delta of wadi zeelim reveals the geological history of that area from the latest pleistocene to present the depositional time frame is based on six 14c dates and two u th dates an erosional or nondepositional period is implied by the hiatus between 21 100 yr b p u th age depth 33 m and 11 315 yr b p 14c age depth 32 m a subsequent arid phase is recorded by a 6 5 m thick layer of halite based on 14c dates this phase relates to the abrupt younger dryas cold period reported in temperate to polar regions the fragility of the environment in this region is indicated by the fact that the region experienced such a severe short aridification phase less than 1000 yr evidence of which is found widely in the desert fringes of the middle east and north africa the aragonite found in most of the holocene section indicates that the well site was covered by the lake for most of the holocene exceptions are the intervals at 0 3 and 10 14 m depths which represent low stands of the lake

holocene climate variability in the levant from the dead sea pollen record abstract the dead sea located at the deepest place on continent and between the subtropical mediterranean zone and the desert reflects in its water composition and levels and sedimentary records the hydrological conditions in the southern levant region temporal variations in rainfall and temperatures of the holocene levant are reconstructed here from pollen data recovered from a sediment core drilled at the ein gedi shore applying a novel biome model based on bayesian statistics our results suggest that the region was arid and warm in the early holocene period 10 6 5 ka cal bp wetter and colder in the mid holocene 6 3 3 3 ka cal bp and drier and warmer in the late holocene 3 2 ka cal bp to present these periods comprise multi centennial climate cycles that are characterized by rapid changes in temperature and precipitation reflecting sea surface temperature sst and atmospheric conditions over the atlantic ocean the pollen record responds within a short time interval to the climate conditions and marks rapid shifts from mediterranean to desert environmental conditions and back in the southern levant region we also evaluate our results in the light of possible disturbances of the natural vegetation e g the possibility of forest decrease since the neolithic

palynology sedimentology and palaeoecology of the late holocene dead sea abstract palynological and sedimentological studies were performed at two holocene profiles in erosion gullies ze elim and ein feshkha which dissect the retreating western shore of the dead sea the aim of the project was to analyse possible links between climate lithology and vegetation development the section in ze elim shows both lacustrine and fluvial sediments whereas sedimentation at ein feshkha is predominantly lacustrine the ze elim profile previously used for paleo lake reconstruction provides an opportunity to compare climate triggered lake levels as paleo hydrological indicators and vegetation history by use of palynology the vegetation development in ze elim and ein feshkha is influenced by both climate and human impact the pollen record of ze elim begins in the pottery neolithic the section of ein feshkha in the late bronze age both records end in the middle ages the ze elim section is characterized by sedimentary hiati between the beginning of the chalcolithic period until the middle bronze age and within the late bronze age settlement periods during the middle bronze age iron age and hellenistic roman byzantine period are indicated by high values of anthropogenic indicators and or mediterranean trees collapses of agriculture which can be related to climate effects are evident during the late bronze age during the iron age and at the end of the byzantine period when the lake level curve indicates arid conditions a comparison of the two pollen records from different environments illustrates a more prominent influence of mediterranean vegetation and cultivated plants in the pollen diagram of ein feshkha the southern dead sea region at the desert fringe is more vulnerable to regional climate change

evidences for centennial dry periods at 3300 and 2800 cal yr bp from micro facies analyses of the dead sea sediments laminated lake sediments from the dead sea basin provide high resolution records of climatic variability in the eastern mediterranean region which is especially sensitive to changing climatic cond

holocene palaeoecology of the golan heights near east investigation of lacustrine sediments from birkat ram crater lake abstract lacustrine deposits of the crater lake birkat ram located in the northern golan heights have been used as a paleoecological archive preliminary sedimentological and palynological investigations based on a composite profile allow the reconstruction of the environmental history of the last 6500 years fluctuations of the pollen composition trees and shrubs versus herbs values of oak and olive tree correspond to changes in different sediment parameters total organic carbon magnetic susceptibility which can be interpreted as the effects of human impact on the geo biosphere four phases with strong settlement activities can be identified for the northern golan heights 1 during the chalcolithic period early bronze age 2 during the hellenistic roman byzantine periods 3 during the crusader period and finally during modern time these periods were interrupted by wooded regeneration phases with low anthropogenic activities

seismotectonics of the sinai subplate the eastern mediterranean region summary we define the sinai subplate from a seismotectonic perspective as a distinct component in the plate tectonics of the eastern mediterranean region this is based on the tectonic characteristics of a comprehensive listing of all ml 4 recorded seismicity in the region during the 20th century on newly calculated and recalculated fault plane mechanisms of first p wave arrivals and on published solutions based on waveform inversion of broad band data the low seismicity level and scarcity of strong events in the region required a thorough search for useful data and a careful examination of the reliability of the focal solutions we gathered all available records of first p wave onsets from the iss and isc bulletins and the local seismic networks altogether we were able to calculate 48 new focal mechanisms and 33 recalculated ones of events that occurred during the years 1940 1992 with the increasing number of teleseismic and regional broad band stations in the later years we added 37 solutions based on teleseismic and regional waveform inversions of events that occurred during 1977 2001 these mechanisms enabled us to examine the seismotectonic character of the sinai subplate the strike and rake directions of the calculated mechanisms usually reflect the geometry and the large scale type of deformation observed along the boundaries of the sinai subplate the dead sea transform the cypriot arc convergent zone and the suez rift nevertheless along each of these boundaries we found anomalous solutions that attest to the complexity of the deformation processes along plate margins earthquakes along the dead sea transform exhibit mainly sinistral transtension and transpression reflecting its leaky manner and local change in the transform geometry the presence of other unexpected mechanisms near the transform however reflects the heterogeneous deformation it induces around as expected thrust mechanisms along the cypriot arc mirror its convergent nature and typical curved geometry transtension and transpressional solutions in the eastern segment of the arc reflect the sinistral shear motion between anatolia and sinai there however shear mechanisms found between cyprus and the eratosthenes seamount pose a problem regarding its collision process most intriguing of all are ml 4 thrust and shear solutions found in the gulf of suez they are associated with predominantly normal mechanisms within a rift zone and therefore constitute a unique phenomenon yet to be deciphered

holocene environmental change and its impact on sediment dynamics in the eastern mediterranean abstract investigators have studied past environmental change in the eastern mediterranean region from a number of perspectives while climate reconstructions and palynological research have focused on forces that drive the geomorphologic system many researchers have attempted to use sediment archive studies to identify periods of change in sediment dynamics due to the large variability in environmental parameters and the variety of landscapes present in the eastern mediterranean region research has focused on sediment archives ranging from small colluvial sites to deltas of large rivers on the mediterranean coast as the cultural record for the region is extremely rich the main goal of palaeo environmental research in the eastern mediterranean has been to identify the relative importance of human impact on the landscape nevertheless sediment archives have significant limitations chronological control for many palaeo environmental records is highly uncertain and rates of landscape change are oftentimes difficult to assess most palaeo environmental research has been conducted on or near archeological sites where direct human impact may obscure the indirect impact on sediment dynamics through land use changes quantification and modeling of sediment dynamics in the eastern mediterranean environment offer one solution when erosion and sediment transport rate analyses are incorporated periods of relatively important change can be identified using multiple approaches the relative importance of the main driving forces climate and land use become distinguishable since field based data from the actual sediment archives remain vital an overview of numerous studies in the eastern mediterranean is provided in order to draw a general picture for different time periods and the relative scale of regional landscape development during the holocene a comparison of sediment dynamics with the record of driving forces indicates that while climate was the main driver of the geomorphic system during the early holocene at some point human impact became widespread and began to dictate sediment dynamics to a large extent from the byzantine period onward soil properties seem to play an increasingly important role as the hillslope soil reservoir in the eastern mediterranean was progressively depleted during the late holocene

the structure of the dead sea basin abstract the dead sea basin is located along the left lateral transform boundary between the arabian and sinai plates its structure and history are known from surface geology drilling seismic reflection and other geophysical data the basin comprises a large pull apart almost 150 km long and mostly 8 10 km wide which is flanked by a few kilometres wide zones of normal faulting the basin formed at about 15 ma or earlier close to the beginning of the transform motion and it reached about half its present length before the end of the miocene a strong negative gravity anomaly records a thick sediment basin fill 5 km under half its length reaching a maximum of 10 km the fill includes a few km of salt ca 6 4 ma which forms several diapirs at any one time large parts of the basin subsided simultaneously but the site of fastest subsidence seems to have shifted northward sedimentation rates reached at least hundreds of metres per million years or more in the miocene and 1 km myr in later periods the basin structure is dominated by longitudinal faults intrabasinal faults which delimit the pull apart and which are the extensions of the major strike slip faults north and south of the basin and normal faults which extend along the basin margins the latter faults express a small component of extension across the basin whereas the pull apart resulted from the much larger lateral motion along the basin in addition transverse faults divide the pull apart into several segments with somewhat different histories the pull apart grew by becoming longer parallel to the transform motion at shallow levels this was probably achieved by normal slip on transverse listric faults while the fill between them was little deformed the crust under the basin was stretched and thinned during basin lengthening which caused its subsidence basin formation was accompanied by uplifting of its flanks by 1 km sparse igneous activity occurred along the basin and its flanks its presence suggests a thermal anomaly in the lower lithosphere beneath the basin and adjacent parts of the transform

mid to late holocene climate change in central turkey the tecer lake record the mineralogy and grain size distribution of sediments from tecer lake in central anatolia provides a 6000 year record of mid to late holocene climate trends and events correspondences between k

13c and 18o of wood from the roman siege rampart in masada israel ad 70 73 evidence for a less arid climate for the region the isotopic ratios 13c12c and 18o16o of cellulose from tamarix trees which were used by the roman army as a groundwork of the siege rampart of masada ad 70 73 were compared with ratios measured in present day tamarix trees growing in the masada region and in central israel the ancient tamarix cellulose is depleted in both 13c and 18o compared to cellulose from trees growing in the masada region today similar trends were observed on comparing modern tamarix trees growing in the negev desert with those growing in the temperate climate of central israel considering the factors that can contribute to the observed changes in isotopic composition we conclude that the ancient trees enjoyed less arid environmental conditions during their growth compared to contemporary trees in this desert region this report demonstrates the potential in using combined 18o and 13c analyses of archeological plant material as independent indication of regional climatic change in desert areas where conventional isotopic analyses such as in tree rings are impractical

vegetation changes during the late pleistocene and holocene in lebanon a pollen record from the bekaa valley a sediment core retrieved from quaternary deposits from the aammiq wetland bekaa valley lebanon provided a pollen record carrying valuable information which allowed reconstruction of past vegetation dynamics in relation to climate change and anthropogenic impacts core stratigraphy and microfossil data helped interpret the depositional settings of the sequence before c 12 2 kyr cal bp an expansion of cedars cedrus libani and deciduous oaks quercus cerris type is observed the younger dryas is marked by the spread of a chenopodiaceae steppe and a regression of cedars and deciduous oaks during the early holocene an open oak forest expanded concomitantly with the development of a marsh in the bekaa valley between c 6 0 and c 3 4 kyr cal bp major disturbances in the sedimentation process are recorded leading to some dissimilarities with other palaeobotanical records from the eastern mediterranean region after c 3 4 kyr cal bp the pollen data reveal that agriculture in the bekaa valley was mainly oriented towards livestock rearing since there is very little record of cultivated plants in this regard the results conflict somewhat with other studies carried out in the eastern mediterranean region where intensive cultures have been observed since the early holocene cultures might have been present in other regions in lebanon but apparently not in this part of the bekaa valley

using palynology to re assess the dead sea laminated sediments indeed varves lacustrine laminated sediments are often varves representing annual rhythmic deposition the dead sea high stand laminated sections consist of mm scale alternating detrital and authigenic aragonite laminae previous studies assumed these laminae were varves deposited seasonally however this assumption has never been robustly validated here we report an examination of the seasonal deposition of detrital aragonite couplets from two well known late holocene laminated sections at the ze elim fan delta using palynology and grain size distribution analyses these analyses are complemented by the study of contemporary flash flood samples and multivariate statistical analysis because transport affects the pollen preservation state well preserved mostly air borne transported pollen was analysed separately from badly preserved pollen and fungal spores which are more indicative of water transport and reworking from soils our results indicate that i both detrital and aragonite laminae were deposited during the rainy season ii aragonite laminae have significantly lower reworked and fungal spore concentrations than detrital and flash flood samples and iii detrital laminae are composed of recycling of local and distal sources with coarser particles that were initially deposited in the dead sea watershed and later transported via run off to the lake this is in line with previous carbon balance studies that showed that aragonite precipitation occurs after the massive input of tco2 associated with run off episodes consequently at least for the holocene ze elim formation laminated sediments cannot be considered as varves older quaternary laminated sequences should be re evaluated

nautiloid shell taphonomy interpretations based on water pressure abstract nautiloid taphonomy is a difficult and widely neglected topic acting as a test of many of the assumptions made in nautiloid paleobiology phylogenetic interpretations and geological facies analysis the eocene nautiloids from the offshore london clay formation of england are considered from the perspective of flooding and implosion experiments on recent nautilus the deeper water facies are often characterized by body chambers in approximate life position one or two complete septa and various types of shell debris intermediate depth facies show intact and often vertically embedded phragmocone walls with zones of internally broken and spar cemented septa taphnomic characteristics of the former facies probably result from the implosion of shells at depths of 200 or 300 m on the seafloor while those of intermediate depth facies result from the sinking of gas filled shells to the seafloor and subsequent bending stress failure of septa left unsupported by sediment in the last whorl evidence for the removal of the body from the largely unbroken shell by octopus illustrates the potential for a biological influence on the taphonomic history of nautiloids through the phanerozoic tertiary nautiloids were probably unusually prone to extensive post mortem transport a process which tends to remove shells from the fossil record under most geological circumstances

late holocene dust accumulation within the ancient town of marea coastal zone of the south mediterranean sea n egypt abstract the ruins of the marea ancient town are located on the southern shore of maryut lake ancient mareotis 45 km to the southwest of alexandria egypt marea was a very important trade religious and agricultural centre in the 5th 7th century a d the area occupied by a town in the past has diversified relief local hills are built of sandstones constituted by calcified dunes the hills are separated by flat depressions of irregular shape the uppermost layer in the depressions covering loam and sand sediments is made up of structureless aeolian dust of 0 6 1 2 m thickness the following analyses of the sediments were conducted granulometric composition the mineralogical composition of samples the loss on ignition the total organic carbon toc organic matter om and calcium carbonate caco3 clay minerals and geochemistry results of osl dating indicate that the filling of the depressions with silt deposits started probably about 2450 years ago and that it is correlated with dust deposition the rate of the dust accumulation was about 0 49 mm year however diversified humus content in the deposits suggests that it was not a permanent process the accumulation took place during intensive dust storms the sediments in the depressions are fine silt and clay with uni and bi modal particle size distribution likely caused by both the local and the regional origin of the material most dust accumulated within the ancient town of marea originated from the border between sahel and sahara local and even regional sources of material were of lower importance geochemical ratios mg ca fe mn and na k distinguished in the deposits of the depressions show that the beginning of the dust accumulation took place during environmental conditions more humid than the contemporary ones that indicates a slight increase in the humidity of climate dated to ca 10th 12th century a d followed by its significant drying initiated ca 15th 16th century a d in addition results of analysis of trace elements suggest that already in the 5th century bc the town of marea or its closest vicinity may have been the site of development of industrial activity much earlier than the age of the oldest artefacts found within the town

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

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

middle east coastal ecosystem response to middle to late holocene abrupt climate changes the holocene vegetation history of the northern coastal arabian peninsula is of long standing interest as this mediterranean semiarid arid region is known to be particularly sensitive to climatic changes detailed palynological data from an 800 cm alluvial sequence cored in the jableh plain in northwest syria have been used to reconstruct the vegetation dynamics in the coastal lowlands and the nearby jabal an nusayriyah mountains for the period 2150 to 550 b c corresponding with the 4 2 to 3 9 and 3 5 to 2 5 cal kyr bp abrupt climate changes accs two large scale shifts to a more arid climate have been recorded these two accs had different impacts on the vegetation assemblages in coastal syria the 3 5 to 2 5 cal kyr bp acc is drier and lasted longer than the 4 2 to 3 9 cal kyr bp acc and is characterized by the development of a warm steppe pollen derived biome 1100 800 b c and a peak of hot desert pollen derived biome at 900 b c the 4 2 to 3 9 cal kyr bp acc is characterized by a xerophytic woods and shrubs pollen derived biome ca 2050 b c the impact of the 3 5 to 2 5 cal kyr bp acc on human occupation and cultural development is important along the syrian coast with the destruction of ugarit and the collapse of the ugarit kingdom at ca 1190 to 1185 b c

four thousand years of seismicity along the dead sea rift a study of major earthquake occurrence along the dead sea transform 35 5 36 5 e 27 2 37 5 n during the past four millenia has been attempted geological archaeological biblical historical and seismological evidence were integrated in an effort to quantify the space time distribution of seismicity in the said province the overall earthquake activity in the conterminous near east indicates a stable pattern and appeared to have been stationary over the examined time window about 110 earthquakes in the magnitude range 6 7 ml 8 3 affected the area during the past 2500 years of these 42 originated along the dead sea fault system itself while 68 were imported from the helenic cyprian arcs and the anatolian elburz zagros fault systems these events were responsible for the repeated destruction of many cultural centers in the dead sea region proper the major seismic activity since 2100 b c e before christian era has been confined to the vicinity of its eastern shore with extremal seismicity at its southern tip near the prehistorical site of bab a dara a 31 15 n 35 32 e this may constitute the first solid evidence that the biblical cities of the plain sodom gommorah etc were located there recent studies of earthquake deformations in the lisan deposits near bab a dara a agree with our findings at the present time a magnitude 6 earthquake is pending at the northern edge of the levant rift with its average recurrence interval 83 years exceeded by one standard deviation 32 years

recharge and salination processes in the carbonate aquifers in israel limestone and dolostone aquifers play a major role in the water supply system of israel in many cases there are brackish to saline springs at their outlets the source of the saline water and the mechanism of salinization differ from place to place in some cases it is due to mixing with seawater mediterranean or dead sea at the fresh saline water interface while in other cases deepseated brines emerge along regional faults the general policy for reclaiming the fresh component of the water before mixing with the saline component is to try to catch the fresh water as far as possible upstream from the outlet in most cases this is the area where the mixing takes place the main case histories in israel are discussed in this paper

climate palaeohydrology and land use change in the central iberian range over the last 1 6 kyr the la parra lake record a multiproxy study of a 7 m long sedimentary sequence from lake la parra 39 50 948 1 52 1014 m a s l supported by 11 14c ams and 210pb 137cs dates provides a robust high resolution hydrological and environmental variability record for the last 1600 years of the las torcas sinkhole complex in the central iberian range the succession of depositional environments in lake la parra sinkhole is controlled by both changes in the regional water table and by the balance between sedimentary input through ephemeral creeks and in lake production of carbonates and organic matter although synergetic links with climate are likely phases of increased sediment delivery to the lake at c ad 500 700 c ad 1000 ad 1450 1500 ad 1550 650 and since 1700 till recent times are driven primarily by human impact in the watershed prior to c ad 300 the sinkhole was dry then became a lake at the end of the roman period ad 350 when the doline was flooded and it has not dried out during the last 1600 years moderate

earthquake deformations in the lisan deposits and seismotectonic implications summary earthquake deformations and induced sedimentary structures preserved in quaternary sediments include faults folds fissures slumps sand boils and other effects of liquefaction such deformations and structures are well preserved in the lisan deposits of the dead sea of most importance are the fold type deformations known as decollement structures which are present all along the eastern side of the lisan and seem to decrease gradually westwards to disappear in the middle of the lisan these may indicate that palaeoearthquakes originating along the araba fault have triggered such structures due to shaking of elastoplastic unconsolidated sediments over gentle slopes dipping to the west preliminary results from studies on decollement structures preserved in a section representing some 1733 years of continuous deposition in the uppermost pleistocene in the vicinity of wadi araba indicate that 1 seismic activity has fluctuated with time average recurrence period is about 340 20yr for earthquakes with magnitudes greater than or equal to 6 5 earthquakes with magnitude greater than 7 seem to have occurred along the araba fault 2 deduced earthquake magnitudes conform to the frequency magnitude relationship log n 5 24 0 68m 3 the deduced seismic slip rate along the araba fault seems to be not less than 0 64 0 04 cm yr 1

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

groundwater flow along and across structural folding an example from the judean desert israel abstract the considerable influence of the geological structure on groundwater flow regime is exhibited in the thick carbonate aquifer beneath the judean desert israel groundwater flow is diverted from the general steep hydraulic gradient creating a subsurface river like meandering flow pattern the structure of the extensive folded anticlinorium forces groundwater flow through synclinal axes in the upper aquifer and in places it overflows from one to an adjacent syncline groundwater outflows are at tsukim kane samar and en gedi springs near the dead sea shore and by sub surface flow across the graben faults towards the dead sea in this study all available data are integrated and processed first ever to form a complete representation of the three dimensional hydrostratigraphy and hydrogeology using numerical modeling modflow we analyzed quantitatively the flow regime leakage rates between upper and lower sub aquifers and between adjacent sub basins the groundwater mass balance and aquifer hydraulic properties this study has practical implications regarding recent groundwater management future possibilities of groundwater development for the benefit of both israelis and palestinians residing in the area and conservation of nature reserves located along the dead sea

application of organic petrography in north american shale petroleum systems a review abstract organic petrography via incident light microscopy has broad application to shale petroleum systems including delineation of thermal maturity windows and determination of organo facies incident light microscopy allows practitioners the ability to identify various types of organic components and demonstrates that solid bitumen is the dominant organic matter occurring in shale plays of peak oil and gas window thermal maturity whereas oil prone type i ii kerogens have converted to hydrocarbons and are not present high magnification sem observation of an interconnected organic porosity occurring in the solid bitumen of thermally mature shale reservoirs has enabled major advances in our understanding of hydrocarbon migration and storage in shale but suffers from inability to confirm the type of organic matter present herein we review organic petrography applications in the north american shale plays through discussion of incident light photographic examples in the first part of the manuscript we provide basic practical information on the measurement of organic reflectance and outline fluorescence microscopy and other petrographic approaches to the determination of thermal maturity in the second half of the paper we discuss applications of organic petrography and sem in all of the major shale petroleum systems in north america including tight oil plays such as the bakken eagle ford and niobrara and shale gas and condensate plays including the barnett duvernay haynesville bossier marcellus utica and woodford among others our review suggests systematic research employing correlative high resolution imaging techniques and in situ geochemical probing is needed to better document hydrocarbon storage migration and wettability properties of solid bitumen at the pressure and temperature conditions of shale reservoirs

alluvial deposition and lake level fluctuations forced by late quaternary climate change the dead sea case example based on geomorphic observations we discuss lake level fluctuations alluvial deposition and river entrenchment in the dead sea wadi araba area the bulk of alluvium in the northern wadi araba was probably deposited before the lisan period of lake transgression that started at about 70 kyears b p the lake reached a maximum elevation about 150 m below sea level b s l possibly around 15 cal kyears b p as indicated by the highest preserved beach ridges cosmogenic exposure dates show that the ridge material consists mainly of remobilized pleistocene gravel indicating little sediment supply during most of the lisan period during this period a reduced sediment flux fed subaquatic fan deltas along the margin of the dead sea wetter conditions settled at the end of this period the water level rose to about 280 m b s l around 15 kyears b p and prevailed in the early holocene 10 5 7 cal kyears b p following that humid period the lake level dropped and two major episodes of fluvial aggradation occurred during periods of relative low lake level the first aggradational episode took place between about 7 0 and 6 2 cal kyears b p beach bars indicate a subsequent lake transgression between 6 2 and 4 4 kyears b p up to 350 m b s l the second aggradational episode happened between 4 4 and 2 0 cal kyears b p and was also followed by a late transgression up to 375 m b s l dated to 1960 1715 cal years b p the correlation between low lake level and fluvial aggradation is taken to reflect the synchronous change of the fluvial regime and of the lake hydrologic balance forced by climate changes rather than a base level control we also exclude large tectonic forcing on fan emplacement and river entrenchment alluviation appears in this setting as a very irregular process characterized by long periods of quiescence alternating with periods of fan build up reflecting the transient response of the water drainage system to climate change d 2003 elsevier b v all rights reserved

long term earthquake clustering a 50 000 year paleoseismic record in the dead sea graben the temporal distribution of earthquakes in the dead sea graben is studied through a 50 000 year paleoseismic record recovered in laminated sediments of the late pleistocene lake lisan paleo dead sea the lisan represents more than 10 times the 4000 years of historical earthquake records it is the longest and most complete paleoseismic record along the dead sea transform and possibly the longest continuous record on earth it includes unique exposures of seismite beds earthquake induced structures associated with slip events on syndepositional faults the seismites are layers consisting of mixtures of fragmented and pulverized laminae the places where the seismites abut syndepositional faults are interpreted as evidence for their formation at the sediment water interface during slip events on these faults thicker sediment accumulation above the seismites in the downthrown blocks indicates that a seismite formed at the water sediment interface on both sides of the fault scarps modern analogs and the association with surface ruptures suggest that each seismite formed during a m l 5 5 earthquake the 230 th 234 u ages of a columnar section obtained by thermal ionization mass spectrometry give a mean recurrence time of 1600 years of m l 5 5 earthquakes in the dead sea graben the earthquakes cluster in 10 000 year periods separated by quiet periods of similar length this distribution implies that a long term behavior of the dead sea transform should be represented by a mean recurrence of at least 20 000 year record this observation has ramifications for seismic hazard assessment based on shorter records

increased frequency of torrential rainstorms during a regional late holocene eastern mediterranean drought identifying climates favoring extreme weather phenomena is a primary aim of paleoclimate and paleohydrological research here we present a well dated late holocene dead sea sediment record of debris flows covering 3 3 to 1 9 cal ka bp twenty three graded layers deposited in shallow waters near the western dead sea shore were identified by microfacies analysis these layers represent distal subaquatic deposits of debris flows triggered by torrential rainstorms over the adjacent western dead sea escarpment modern debris flows on this escarpment are induced by rare rainstorms with intensities exceeding 30 mm h 1 for at least one hour and originate primarily from the active red sea trough synoptic pattern the observed late holocene clustering of such debris flows during a regional drought indicates an increased influence of active red sea troughs resulting from a shift in synoptic atmospheric circulation patterns this shift likely decreased the passages of eastern mediterranean cyclones leading to drier conditions but favored rainstorms triggered by the active red sea trough this is in accord with present day meteorological data showing an increased frequency of torrential rainstorms in regions of drier climate hence this study provides conclusive evidence for a shift in synoptic atmospheric circulation patterns during a late holocene drought

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

medieval coastal syrian vegetation patterns in the principality of antioch the coastal area of jableh in the vicinity of the saladin and al marquab castles is a fertile alluvial plain located on the northwestern part of syria in what was once the crusader principality of antioch in order to detail the coastal environment during the crusader period in the middle east palynological analyses have been conducted on the underlying coastal alluvial deposits the recovered sediments represent a continuous record of the environmental history of the area spanning a c ad 850 1850 cal yr period from the muslim era up to and including the late ottoman times during the local crusader period ad 1100 1270 the area was dominated by an arborescent mattoral mixed with a xerophytic shrub steppe the alluvial plain was slightly waterlogged and colonized by a wetland meadow with an open vegetation of steppe like character on bare surfaces and fresh arable soils the riparian and open deciduous riverine forests were weakly developed signs of agricultural activities are mainly recorded for the high medieval period ad 1000 1300 with an increase of vineyards in the coastal area since c ad 1250 cal yr until the end of the crusader period agricultural activities never reached the same intensity as during the mameluke sultanate and the ottoman empire

abrupt aridities and salt deposition in the post glacial dead sea and their north atlantic connection abstract abrupt arid events in the post glacial 17 4 10 kyr bp dead sea basin dsb were recorded by significant lake level declines in lake lisan and massive deposition of gypsum and salt between 17 4 and 16 kyr cal bp the lake level dropped from its late mis2 stand of 260 m below mean sea level m bmsl to 330 m bmsl depositing a thick sequence of gypsum between 16 and 15 kyr cal bp the lake level recovered but dropped abruptly again at 14 kyr cal bp to below 465 m bmsl probably the lowest late pleistocene stand then between 13 and 11 kyr cal bp the younger dryas time interval the lake rose above 400 m bmsl and declined at 11 10 kyr cal bp depositing a thick sequence of salt the abrupt lake level drops and salt deposition coincided with times of ice and meltwater discharges into the north atlantic na heinrich event h1 and meltwater pulse mwp1a similar coincidence between ice and meltwater discharges in the na e g h events and arid episodes at the levant was recorded during the colder last glacial period demonstrating a persistent effect of the north atlantic hydrology and sea ice advances on the levant climate the climatically turmoil post glacial period was accompanied by significant developments in human culture the collapse of the natufian culture during the bolling allerod and the rise of the pre pottery neolithic cultures ppn a and b around the 11 10 kyr cal bp salt deposition interval marking the initiation of the neolithic revolution in the region

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

holocene climate variability and cultural evolution in the near east from the dead sea sedimentary record abstract a comprehensive record of lake level changes in the dead sea has been reconstructed using multiple well dated sediment cores recovered from the dead sea shore interpreting the lake level changes as monitors of precipitation in the dead sea drainage area and the regional eastern mediterranean palaeoclimate we document the presence of two major wet phases 10 8 6 and 5 6 3 5 cal kyr bp and multiple abrupt arid events during the holocene the arid events in the holocene dead sea appear to coincide with major breaks in the near east cultural evolution at 8 6 8 2 4 2 3 5 cal kyr bp wetter periods are marked by the enlargement of smaller settlements and growth of farming communities in desert regions suggesting a parallelism between climate and near east cultural development

palaeoenvironment and anthropogenic activity in the southeastern mediterranean since the mid holocene the case of tell es safi gath israel abstract the younger fill phenomenon defined by vita finzi related to sediments that were deposited in many mediterranean valleys has been a topic of discussion for several decades the main challenge regarding this issue is deciphering the origin of the fill geomorphic processes induced by natural climatic or by anthropogenic activity the current research is an attempt to deal with this issue by using a concept in which the environmental records i e climate hydrology and sedimentology were examined in conjunction with human history in the area of the bronze and iron age archaeological site of tell es safi gath in central israel the study investigated geomorphic structures of various scales a single slope 1st and 2nd order valleys and larger drainage basins of a few tens to hundreds km 2 high resolution dating of the sediments by osl and 14 c allowed the identification of different sedimentary phases the sedimentary history of the tell es safi gath environs shows that a during the chalcolithic period and early bronze age 4200 3050 bce stable conditions prevailed in the small valleys represented by soil formation b during the iron age ii and up to the early arab period 800 bce 800ce aggradation took place in the small and the large valleys c during the post byzantine early arab periods after 800 ce major incision occurred in the large valleys whereas minor aggradation occurred in the small valleys climatic and natural geomorphic processes are the major factors shaping the landscape in the current research area anthropogenic activity was expressed at localized sites and for a limited time in two locations only one location is the siege trench that surrounds tell es safi gath where sedimentation occurred shortly after the destruction of the site by hazael king of aram damascus ca late 9th century bce and in the same locality during the byzantine period the other location is the 2nd order valley close to the archaeological site where enhanced sedimentation rates occurred shortly after site destruction in addition these results suggest that the small basin valleys underwent aggradation that continuously recorded the local environmental history whereas the large drainage basins underwent cut and fill processes related to the regional environmental history in a less continuous record

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

the late holocene climate change vegetation dynamics lake level changes and anthropogenic impacts in the lake urmia region nw iran two short 100 and 175 cm long sediment cores from the southwestern corner of lake urmia provide a record of vegetation dynamics lake level changes and the role of climate and humans in shaping the landscape around lake urmia over the last 2550 years relatively low values of arboreal pollen ap and substantial values of artemisia pollen from 2550 to 1500 cal bp indicate the prevalence of steppe vegetation and relatively arid climate in the area however a prominent peak of riella spores may indicate a short lived lake level rise for the period 1900 2000 cal bp the next period 1500 550 cal bp is characterized by substantial rise in ap particularly quercus and a sharp decline of artemisia chenopodiaceae amaranthaceae and wetland pollen types suggesting the expansion of oak forests under a rather moist climate and or a decline in agro sylvo pastoral practices in the area agricultural activity in the area can be inferred from sporadic occurrences of vitis ricinus and juglans pollen from the beginning of the record the rise of saline habitat pollen types between 1100 and 800 cal bp along with increased values of magnetic susceptibility and organic matter suggest a lower water level and the subaerial exposure of saline mud flats which could favour the re colonization of chenopods and other halophytes around the margins of the lake thus the medieval climatic anomaly seems to be warmer than present in the lake urmia region from 450 to 150 cal bp the decline in quercus and high values of artemisia along with higher lake levels and high magnetic susceptibility values could be associated with the little ice age since 500 cal bp quercus and riella steadily decline and fade out towards the surface of the core whereas pollen types attributable to steppe and desert vegetation increase a prominent increase in organic matter in the uppermost part of the record could be associated with a lower lake level and the expansion of wetland vegetation in the recent past our findings suggest that the regional forest coverage in the highlands of zagros and azerbaijan has reached its minimum during recent decades while urmia s lake level dropped dramatically increasing its water salinity most likely as a function of extensive anthropogenic activities and general climate aridification c 2015 elsevier ltd and inqua all rights reserved