dating loess up to 800 ka by thermoluminescence thermoluminescence tl ages agreeing with expected ages have been obtained for 13 loess samples spanning the age range from 20 to 800 ka our samples are from alaska and north island new zealand and are unusual in tl dating studies of loess older than 80 100 ka by having independent age assignments that are generally well constrained from ages of associated tephra beds with the polymineral fine silt sized 4 11 m grains the partial bleach tl technique yielded expected ages up to about 350 ka whereas the total bleach method gave accurate ages in the range 100 to 800 ka thus the much disputed upper age limit of 100 150 ka for the tl dating of loess now appears to be sample and worker dependent rather than a global property of the tl signals in the tl dominant feldspars

new discoveries at the middle pleistocene acheulian site of gesher benot ya aqov israel abstract the gesher benot ya aqov archaeological site in the northern dead sea rift of israel contains acheulian artifacts and middle pleistocene fossils initial results of a new interdisciplinary study have shown that fluviolacustrine sediments of the benot ya aqov formation which contains several archaeological occupations were deposited in an embayment of the hula basin they were subsequently deformed by tectonic activity associated with the dead sea rift biostratigraphy magnetostratigraphy and k ar dating serve to constrain the age of the benot ya aqov formation to between 240 000 and 730 000 yr b p archaeological excavation of three areas and two trenches at the new study area have produced abundant basalt flint and limestone artifacts mammalian and avian fossils and considerable plant material the lithic materials provide an excellent opportunity to study large assemblages of in situ acheulian artifacts a rare phenomenon in the middle pleistocene levantine record in addition the organic materials will facilitate paleoenvironmental reconstructions from an ecological floral perspective

optical dating using infrared diodes young samples abstract ages are reported for unburnt sediment samples from 9 archaeological sites in england spanning 1000 5000 years samples from two modern contexts have also been measured

evidence from luminescence for late pleistocene formation of calcareous aeolianite kurkar and paleosol hamra in the carmel coast israel abstract calcareous aeolianite kurkar and red loamy paleosol hamra units form ridges in the northern coastal plain of israel the kurkar ridges with hamra units have been thought to be indicators of past sea levels and of palaeoclimate though there has been no clear chronology that could correlate units from one ridge to another or to global palaeoclimate and sea level change we obtained detailed stratigraphy and luminescence ages for the kurkar and hamra units that range from 35 to 101 ka indicating coeval formation of these units during the late pleistocene independent dating suggests that hamra and similar loamy soils formed at 45 to 130 ka in the habonim quarry site at the eastern ridge when kurkar that has been dated by us to 50 67 ka was deposited in the coastal trough showing facies changes from west to east the youngest ages for exposed kurkar in the dor islet at the coastal ridge 35 and 38 ka are close to the 35 ka age obtained independently for the upper kurkar near atlit at the eastern ridge at that time when kurkar was deposited and cemented on the top of both ridges a hamra dated by us to 37 ka formed in the coastal trough our results indicate that kurkar accumulated along the coastal plain at different time intervals throughout the late pleistocene and that its deposition was not necessarily associated with high sea levels moreover our data as well as previous research suggest that hamra also formed at different periods sometimes synchronous with kurkar and its formation is therefore not related to any particular climatic events

chronology of upper quaternary offshore successions from the southeastern mediterranean sea israel pleistocene and holocene transgressions advancing over the shelf that was exposed during glacial maxima drowned any continental and shallow marine sediments deposited during low sea level stands to complement records from sequences exposed on land core material from the shallow continental shelf is needed to reconstruct climatic and sea level fluctuations two cores drilled offshore ashqelon off the southern mediterranean coast of israel in a water depth of 10 and 25 m were analyzed sedimentary facies and faunal analyses indicate that most of the sediments were deposited in nearshore environments with only short intervals of continental episodes luminescence dating of alkali feldspar and quartz as well as 14 c ages of mollusks date the cores to marine oxygen isotopic stages 6 1 between b140 and 5 ka comparison between the dating methods shows that most alkali feldspar ages agree with independent sea level and sedimentological constraints while quartz ages are overestimated r 2003 elsevier science ltd all rights reserved

tl dates of burnt flints from jelinek s excavations at tabun and their implications abstract a selection of 37 burnt flints from jelinek s excavations at tabun were dated by thermoluminescence the results indicate that the bottom of unit i garrod s layer c should be given an age of 171 17 ky bp transition from oxygen isotope stage 7 to 6 and that units xiii to ii layers ed to d were deposited between c 330 and 210 ky bp i e during the oxygen isotope stages 9 8 and the beginning of 7 these dates raise the possibility that a a pre wurmian neanderthal population may have settled in the levant during the oxygen isotope stage 6 and that b the transition from mugharan acheuleo yabrudian yabrudian and amudian to levallois mousterian type lithic industries occurred at the end of stage 8 more than 200 ky ago these early dates whose reliability was consistent with isochron analysis of the data are not that different from those now accepted for the development of the levallois mousterian industries in europe

vesta s shape and morphology vesta s surface is characterized by abundant impact craters some with preserved ejecta blankets large troughs extending around the equatorial region enigmatic dark material and widespread mass wasting but as yet an absence of volcanic features abundant steep slopes indicate that impact generated surface regolith is underlain by bedrock dawn observations confirm the large impact basin rheasilvia at vesta s south pole and reveal evidence for an earlier underlying large basin veneneia vesta s geology displays morphological features characteristic of the moon and terrestrial planets as well as those of other asteroids underscoring vesta s unique role as a transitional solar system body

thermoluminescence dating of sand dunes in rajasthan india we report here a new application of thermoluminescence tl for dating sand dunes this application assumes that exposure to sunlight causes bleaching of the geological tl of a sediment to a residual value and that tl accumulation starts again when the sediment is buried under fresh deposit and is thus shielded from the sun although the tl method has been applied to loess1 2 and ocean sediments3 4 the application of this technique to sand dunes provides the first reliable dating control for dune dynamics palaeoclimatology and spread of deserts

residual ages of modern sediments in an hyperarid region israel modern sediments from a variety of depositional environments in the hyperarid southern arava region israel were analyzed for their residual equivalent dose d colluvial and uvial sediments from drainage systems of di erent sizes and parent materials were collected and alkali feldspars were measured using the single aliquot additive dose protocol all samples showed a large scatter in the d s for most types of the sediments the average d is between 2 and 11 gy equivalent to residual ages of 1 5 ka the lowest d is usually in the range of 0 1 4 gy con rming that the single aliquot protocol can identify the best bleached grains newly weathered material from active channels gave the largest d s of up to 30 gy reworked uvial sediments derived from terraces and fans gave progressively smaller d s with increasing level of recycling the degree of bleaching of colluvial sediments strongly depends on the face of the slope the high d s and the large scatter result from the mode of sediment transport brief rain episodes result in ash oods where large volumes of sediment are transported over short distances and only a small part of the sediment is exposed at any time to the sun only repeated cycles of transportation can homogenize the sediment and fully expose all its particles to the sun single grain or small aliquot protocols can overcome the high and variable residual d values and enable better dating of sediments in hyperarid environments 2000 elsevier science ltd all rights reserved

evaluation of luminescence dating procedures applied to late holocene colluvium near st paul s mission natal south africa colluvial deposits provide an interesting challenge for luminescence dating techniques because of the short and varied light exposure histories of the grains prior to deposition results of thermoluminescence tl and infrared stimulated luminescence irsl measurements are presented for two stacked colluvial deposits from natal a radiocarbon date for bulk organic matter in the a horizon of the soil formed within the surface of the lower unit provides a means of assessing the suitability of various luminescence procedures for such material the overlying colluvium contains grains bleached to varying extents as shown by the range of eds for the coarse grain feldspar separate obtained using the single aliquot irsl method for this sample all age estimates either by irsl or tl are too large compared with the radiocarbon age indicating that even the irsl signal was not zeroed in all grains before they were buried the underlying colluvium contains grains bleached more uniformly resulting in a smaller ra

flint thermoluminescence dates from the cfr laboratory at gif contributions to the study of the chronology of the middle palaeolithic abstract flint tools are among the most durable objects marking the presence of prehistoric humans methodological advances of the last decade have made thermoluminescence of burnt flint a reliable dating tool and have provided new dates which require reassessment of the chronology of numerous middle palaeolithic sites dates for several near eastern sites show the presence of neanderthals from at least oxygen isotope stage 6 until after 50 ka ago and push the appearance of modern humans to before 100 ka ago long before their arrival in europe whether the two populations were present continuously or intermittently and precisely when they appeared is uncertain at the moment thermoluminescence results suggest that the mousterian lithic industries were introduced at about the same time in europe as in the near east with the difference that in the latter area this industry was used by early modern humans as well as by neanderthals the new tl chronology assigns a much longer life span to specific types of levantine mousterian lithic industries than previously believed finally new dates for the ch telperronian site of saint cesaire open up the possibility that the last neanderthals were still present after some cro magnons had already settled in western europe

laser ablation depth profiling of u series and sr isotopes in human fossils we have explored laser depth profiling to obtain data sets for u series as well as sr analyses laser probing with an 81 m spot size allows for the exploration of low uranium domains of up to 400 m below the outer surface in tooth enamel these low u domains will contain sr isotope compositions of the individual that are least affected by diagenetic sr overprints the small holes drilled for u surveying are not visible to the naked eye using larger spot sizes of around 233 m laser drilling can be used to obtain reliable u series isotope data to a depth of approximately 1000 m in enamel and around 1300 m in bone furthermore meaningful 87sr 86sr isotope data can also be obtained with this spot size using our sampling strategy the overall damage to a human tooth is minute as demonstrated on a neanderthal tooth from moula guercy we expect that laser ablation depth profiling will become routine for gaining insights into the age of human fossils and the migrations of ancient humans

late quaternary earthquake chronology from luminescence dating of colluvial and alluvial deposits of the arava valley israel abstract luminescence ages help provide a time scale for recurrent surface ruptures on a normal fault in the southern arava israel the dated samples come from alluvium and colluvium along a fault scarp north of elat the ages obtained mainly by infrared stimulation of sand size potassium feldspar grains accord with geomorphic age estimates from soils and degraded scarps four large earthquakes occurred between 37 000 and 14 000 yr ago five smaller earthquakes occurred thereafter continuing until recent times the mean recurrence interval for earthquakes of magnitudes greater than 6 is about 4000 yr

esr dating of micoquian industry and neanderthal remains at kůlna cave czech republic abstract electron spin resonance esr and mass spectrometric u series dating has been carried out on teeth recovered from k lna cave during the excavations of 1961 76 linear and early uptake lu and eu age estimates are similar due to low internal u content of the teeth in general esr ages decrease upward in the section but teeth from stone rich lumpy layers give anomalously young ages due to uneven dose rate distribution elephant molars also give anomalously low ages apparently due to self absorption of gamma dose disregarding anomalous data earliest appearance of micoquian lithics and last occurrence of dicerorhinus kirchbergensis in layer 9b is dated to 69 8 ka which places them near the oxygen isotope stage ois 5a 4 boundary neanderthal remains and the latest occurrence of micoquian lithics in level 7a are dated to 50 5 ka in good agreement with an uncalibrated radiocarbon date for this level of about 45 ka the interstadial character of the fauna of this level also agrees with its date which places it in ois 3 we also report that three stadial interstadial cycles recognized in the lithological faunal and palynological record of levels 9b through 7a at kolna occurred during the timespan from about 70 to 50 ka

luminescence dating of sediments using single aliquots new procedures abstract the application of luminescence dating to quaternary sediments has been hampered by the labour intensive procedures involved determination of equivalent doses using single aliquots measured using an automated luminescence reader offers a significant reduction in labour equivalent dose determinations using two single aliquot additive dose methods are compared with equivalent doses measured using standard multiple aliquot methods for a suite of 12 dune sand samples from southwest north island new zealand the single aliquot correction method based upon adjusting the magnitude of the measured luminescence signal is found to give underestimates for those samples whose equivalent dose is greater than 80 gy and whose luminescence response to dose is non linear a second correction method based upon adjusting the value of the total added dose that the sample has received is described this second method gives equivalent dose results similar to those measured using standard multiple aliquot methods over the range from 0 1 to 400 gy

optical dating studies of quartz and feldspar sediment extracts abstract continuing developmental work into optical dating has led to some clarification of the optical behaviour of quartz and feldspar sediment extracts we have verified the key assumption intrinsic to the method that the optical signal is zeroed completely upon exposure to daylight we also show that the rate of zeroing in optical dating is much more rapid than it is in tl dating studies concerned with the extraction of the thermally stable signal from laboratory irradiated samples showed that problems may arise from medium to high temperature preheating of young samples optical alternatives to thermal stabilization were tested using dye and krypton lasers using a krypton laser we have succeeded in obtaining an equivalent dose of 0 0 0 7 gy for the quartz from a modern intertidal sand and an average dose of 120 22 gy for the feldspar extract of a 70 ka sand unit both were obtained using six wavelengths from the infrared to the violet and no dependence on wavelength was found we found that the photon energies of infrared and deep red light can stimulate luminescence in unirradiated quartz and feldspar extracts of sediments this was not expected and suggests that the process of trap emptying is more complex than we had envisioned but implies a far greater than expected degree of technical flexibility for the optical dating method

soil chronosequence development in dunes on the southeast african coastal plain maputaland south africa abstract dunes have accreted on the southeast african coastal plain in coast parallel patterns of degraded whaleback ridges sand megaridges and extended parabolic dunes since the pliocene in the maputaland dune field relative dating is complicated by soil degradation erosion and vegetation cover this project assessed alternative relative and numeric dating techniques that can be used to differentiate dune systems and eolian sand bodies soil profile characteristics were used to calculate soil development indices sdi for soil horizons sampled from hand augered holes and rare exposures infrared stimulated luminescence irsl dating of representative dunes and sand units helped define the pedogenesis achieved since deposition the quartzose dune sands have weathered to form very deep soil profiles enhanced sdi values for horizons or sampled intervals down the profile reflect ph decrease advanced rubification or distinct mottling clay increase and harder consistency with depth the youngest holocene profiles exhibit decreasing horizon index values with depth below the a horizon whereas late pleistocene profiles display sdi values increasing with depth within the upper 3 m of the profile within some mid to late pleistocene eolian sands greater profile horizonation and catena complexity manifests as complex soil profiles or distinctly mottled clay enriched horizons at depths of 2 5 m below the surface the sdi profiles from specific dune systems or stratigraphic units cluster well and effectively characterize soil development in dune sand units of different ages depositional age plotted against sampled horizon index values makes it possible to determine generalized rates of soil profile development and to compare pedogenic processes on the high rainfall coastal barrier dunes to those found in the drier interior sampled horizon index values distinguish buried soil profiles and highlight possible localized surficial reworking

further thermoluminescence dates from the dune sequence in the southeast of south australia abstract our thermoluminescence dating technique has been applied to several new samples from the remarkable sequence of stranded beach dunes in southeast south australia that were formed during the past 800 ka we show that robe iii is probably 100 ka as suggested by schwebel and not 80 ka as we suggested earlier a sample from the west dairy dune is shown to belong to 18 o stage 7 in accordance with schwebel s original suggestion and not stage 5 as he suggested later a new west naracoorte sample yielded acceptable data and an age consistent with formation just after the brunhes matuyama magnetic reversal at 780 ka as required by palaeomagnetic measurements two more samples from the woakwine dune show that our reproducibility is consistent with our derived errors

electron spin resonance esr dating abstract esr dating has been systematically applied in earth sciences and archaeology since 1975 when ikeya dated a stalactite from the akiyoshi cave in japan in the meantime this new technique has been successfully applied to the dating of materials such as speleothems spring deposited travertines mollusc shells corals and tooth enamel the present research focuses on the dating of quartz which allows the age assessment of heated ceramics volcanic rocks intrafault material or windblown sediments esr dating is based on the measurement of the number of paramagnetic centers in a mineral these centers are generated by alpha beta and gamma radiation of the matural radioelements such as u th and k and have accumulated over time two parameters have to be determined the accumulated dose ad and the dose rate d to which the sample was exposed this review comprises three major parts a introduction into esr dating b application of the method and c appendices giving detailed description of dose rate calculation physical basis of electron spin resonance the esr spectrometer and esr lines the major emphasis lies on the outline of the application of esr dating this includes the discussion of the esr signals of the various materials sampling sample preparation and measurement techniques

relief inversion in the avrona playa as evidence of large magnitude historical earthquakes southern arava valley dead sea rift the arava valley section of the dead sea transform dst in southern israel is characterized by the absence of seismic activity in recent times however paleoseismic analysis of sediments in the avrona playa a pull apart basin along the dst reveals that at least six m 6 tectonic events have affected the avrona playa in the last 14 000 yr the recurrence interval of the events is approximately 2000 yr trenched normal faults and push up ridges in the playa show that the upper 2 m of the deformed sedimentary sequence consists of playa deposits with uniform soil development the deformed sediments and the soil are typical of basins with an endoreic fluvial system based on the limiting age of the sequence and the extent of soil development faulting in the playa followed by compression and uplift occurred in the last 1000 yr this most recent tectonic event displaced the surface by at least 1 m consistent with a m 6 5 earthquake this earthquake changed the morphology of the avrona playa from a closed system with internal drainage to an open basin resulting in relief inversion the seismic quiescence in the arava may indicate a seismic gap in this segment of the dst

the faunal remains from evron quarry in relation to other lower paleolithic hominid sites in the southern levant abstract the mammalian assemblage and archaeological finds from the lower palaeolithic hominid site of evron quarry situated on the northern coastal plain of israel are described and discussed in their lithic and faunal composition the sites of latamne qfiii latamne formation orontes syria and sitt markho nahr elkebir syria resemble evron and are probably contemporaneous it is suggested here based on their lithic and faunal composition that these sites may be chronologically closer to the site of ubeidiya ubeidiya formation jordan valley israel 1 4 myr than to the sites of gesher benot ya akov dated as

optical dating using inclusions within quartz grains a sequence of stranded beach dunes in the southeast of south australia which resulted from the advance and retreat of the sea over a tectonically rising land surface during the past 800 ka has been securely dated by geological means and successfully used to test thermoluminescence dating based on quartz we have now obtained a series of promising results from the same sequence with a test of optical dating on inclusions within the quartz grains the innovative aspect of the measurements is the use of infrared irradiation to stimulate emission from the inclusions rather than conventional stimulation of the quartz itself by light of shorter wavelength satisfactory ages were found for seven dunes covering the time span 0 400 ka

aeolian beach ridges and their significance for climate and sea level concept and insight from the levant coast east mediterranean abstract relict beach ridges of aeolian origin and associated soils are often used for inferring relative sea level and climate with contrasting results most studies link the aeolian coastal deposits to regressive phases some to high sea level stands and a few to intermediate relative sea level positions we interpret the apparent contradictions as indicating the lack of an over arching concept and the inconsistent usage of sea level related terms in this paper we present an integrated morpho sedimentological concept for a microtidal mid latitudinal coast and review existing data from the levant east mediterranean coast to evaluate the concept and to eliminate nomenclatural confusion a coastal depositional environment in a semi arid environment consists of shallow marine aeolian and alluvial facies which together form an aeolian beach ridge complex as a package of strata which respond simultaneously to sea level change a transgressive complex forms through reworking or overstepping of the coastal foredune and a regressive complex forms by downstepping under transgression the aeolian beach ridge represents the highstand deposit and its adjacent shallow marine sediment is the transgressive deposit under regression the complex represents the falling stage and the associated downdip surface marks the lowstand on the levant coast we find chronologically well constrained offlapping aeolian beach ridges as parts of six downstepping beach ridge complexes formed between 200 ka and 10 ka the complexes represent the falling stage systems tract fsst of a short lived 5th order depositional sequence when the shoreline shifted from a position close to the modern coastline to the shelf or below the shelf edge three of these fssts and their up dip and down dip super bounding surface together form the 4th order 100 ka sequence of the last interglacial glacial cycle the absence of transgressive highstand and lowstand systems tract is explained by the poor preservation potential due to the small sediment budget of the complex the falling stage complex has a high preservation potential because sediment source area increases while the sand drift potential remains above the local threshold on the levant coast sand delivery to the backshore continued during relative sea level falls for distances of up to 10 km between dune and coastline which is unprecedented in most modern analogues the significance of the dune soil succession for climate is limited because the dunes are governed by relative sea level change the vegetation response to changes in precipitation is non linear and the dune dynamics are characterised by low resilience and hysteresis

the luminescence chronology of dune development on the maputaland coastal plain southeast africa abstract geomorphological and lithostratigraphic mapping of dune systems on the maputaland coastal plain of northeastern kwazulu natal province south africa has defined the relative age relationships between the complex pattern of quaternary parabolic and hummocky dunes sand megaridges and the composite coastal barrier dune cordon here infra red stimulated luminescence irsl ages are presented in the context of regional stratigraphic relationships and serve to bracket the period of accumulation of the main dune systems the luminescence ages challenge the widely held belief that the north south aligned dune pattern reflects a coastward younging sequence the framework of ages highlights the spatial variations in dune mobilization and long accretion history on some dune forms weathered dune and interdune wetland sediments spanning from prior to marine isotope stages mis 11 and up to mis 7 underlie the coastal plain at least two generations of decalcified aeolianite of mis 5 and 4 form the core of the complex coastal barrier dune on the coastal plain frequent sand mobilization events during mis 3 2 resulted in the development of discrete complexes of highly extended northward directed parabolic dune systems and reworking of the crest of the central sand megaridge the luminescence dated dune mobilization history brackets the period of formation of interdune and lacustrine peat and diatomite deposits during the holocene marine transgression at least four laterally extensive complex transverse ridges of coalesced ascending parabolic dunes accreted against the aeolianite core of the coastal barrier polyphase dune formation and remobilization is discussed in the context of the regional groundwater and vegetation responses to global climatic changes wind regimes and glacio eustatic sea level fluctuations

dating the lower paleolithic open air site of holon israel by luminescence and esr techniques abstract the open air acheulian site in holon israel was dated by the luminescence methods and by electron spin resonance esr situated in the coastal plain quaternary kurkar group the holon site was first excavated in the late 1960s when typical lower paleolithic lithics and middle pleistocene fauna were found in order to date the site new test pits were dug adjacent to the earlier excavations and the archaeological bed was exposed in a section comprising a series of paleosols and aeolianites alkali feldspars separated from the sediments were dated using the infrared stimulated luminescence and thermoluminescence signals and quartz was dated using the optically stimulated luminescence signal the age of the archaeological bed is constrained by two samples to 198 000 22 000 201 000 17 000 yr the age of the base of the section is 240 000 29 000 yr and the age of the top is 81 000 8000 yr two teeth from the archaeological bed recovered from the original excavation collection yielded an average esr age of 204 000 16 000 yr calculated using the linear uptake model which is in a very good agreement with the luminescence ages these dates place holon within the range of other late acheulian and acheulo yabrudian sites in this region such as tabun e younger chronology yabrud i archaeological level 18 and berekhat ram

the human colonisation of australia optical dates of 53 000 and 60 000 years bracket human arrival at deaf adder gorge northern territory the date at which people entered australia has important implications for the debate on modern human origins thermoluminescence dates of 50 60 ka reported for initial occupation of the malakunanja ii site in northern australia have been used as a means of calibrating the rate of mitochondrial and nuclear dna evolution in modern humans optical dating of unburnt quartzose sediments from a rock shelter site nauwalabila i lindner site in deaf adder gorge 70 km south of malakunanja ii provides new evidence for the timing of the colonisation of the continent optical dates were determined for several stratigraphic levels within a 3 m deep excavation in which flaked stone artefacts and ground pigments were found in primary depositional setting the lowest human occupation levels are bracketed by dates of 53 4 5 4 ka and 60 3 6 7 ka while the upper levels show good agreement between optical and calibrated 14c age estimates high quality haematite with ground facets and striations is associated directly with the 53 ka level and indicates the use of pigments by these early australians the optical dates independently confirm evidence for the colonisation of northern australia shortly after 60 ka and should be seen in the context of this region as having been a likely entry route for the first human movements into sahul

thermoluminescence dating tests for lacustrine glaciomarine and floodplain sediments from western washington and british columbia to help further develop reliable procedures for accurate thermoluminescence tl dating of quaternary waterlaid sediments we tested tl dating procedures on sediment types rarely examined six glaciolacustrine samples three samples of glaciomarine drift and eight samples of floodplain deposits we used the partial bleach r beta gamma technique applied to fine silt polymineral grains results from our younger known age glaciolacustrine sediments confirm earlier observations that only the clayey laminae are generally suitable for tl dating a clayey lamina older than ca 140 150 ka produced no age underestimation and this result ca 300 ka suggests that such older lake sediments are probably suitable for tl dating two proximal samples of glaciomarine drift produced large tl age overestimates whereas the single distal glaciomarine drift sample yielded an expected age 177 38 ka suggesting that follow up studies are warranted our results for eight flood plain samples confirm that zeroing of li

brunhes epoch paleoclimates of japan and israel abstract continuous pollen diagrams for the brunhes epoch two from lake biwa japan and two from the dead sea rift israel are the basis for reconstructing paleoenvironments and paleoclimatic trends on both sides of asia east and west at approximately the same latitudes the mid 30 n the paleoclimatic curves are compared and correlated with the ocean oxygen isotope records the correlation is based on detailed and better dated climatic models obtained for both localities for the last 100 150 k y generally similar climatic trends have been observed for both sides of asia correlating to the oxygen isotope curves the glacial phases are manifested by cooler and more humid periods the interglacials by a temperate climate in japan and a warm dry climate in israel local climatic responses to global cooling or warming differ in japan and israel and peaks of the oxygen isotope curves may appear amplified or reduced in any of the regions the climatic responses to global processes differ from japan to israel in terms of amplitude but not the style of changes the causes for these differences in amplitude may lie with either the different local conditions japan being mainly controlled by the ocean while israel is strongly influenced by the sahara or differences in the global distribution of ice through the ages not recorded in the oxygen isotopes as long as the ice volume remains constant

optical dating of sediments a new method for dating sediments is proposed which determines the time since the sediment was last exposed to sunlight an argon ion laser is used to excite electrons from thermally stable light sensitive traps and the subsequent luminescence used as a measure of the past radiation dose two sample sequences spanning the periods 0 700 kyr and 0 6 kyr show steadily increasing luminescence with age an age of 62 8 kyr is obtained for a silt radiocarbon dated at 58 8 0 3 kyr problems were found with two much younger samples

distribution of aliphatic des a triterpenoids in the dajiuhu peat deposit southern china abstract aliphatic des a triterpenoids have been tentatively assigned in samples taken from a 260 cm thick peat sequence from the dajiuhu basin of southern china using gas chromatography mass spectrometry gc ms the compounds possessing the carbon skeletons of oleanane ursane or lupane are generally considered as the microbial degradation products of plant triterpenoids under anoxic conditions abundant aliphatic des a triterpenoids were observed only in peat samples during the transitional period from the last glaciation to the early holocene 9 5 11 6 cal 14 c ka bp among these des a lupane is the only saturated ring a degraded compound whilst mono and di unsaturated des a triterpenes are dominated by oleanane and ursane derivatives the mono and di unsaturated des a triterpenes show a strong correlation r 2 0 94 in abundance indicating that they may be derived from the same source or process des a lupane shows no correlation in abundance with the mono or di unsaturated des a triterpenes r 2 des a triterpenoids corresponds to the interval with relatively high sedimentation rate 0 3 mm per year these data indicate that the abundance of aliphatic des a triterpenoids in the dajiuhu peat deposit in the early holocene may result from the prevailing reducing conditions in the water table or surficial sediment and or rapid preservation of the early diagenetic products our study highlights the potential application of des a triterpenes in the reconstruction of palaeoenvironments based on peat sequences