burnt bone assemblages from el esquilleu cave cantabria northern spain deliberate use for fuel or systematic disposal of organic waste abstract bones or fossil fuels associated with combustion structures have been widely discussed in several works related to neanderthal lifestyles and subsistence patterns during the mis 3 el esquilleu cave western cantabria spain can significantly contribute to this issue particularly with the taphonomic study of layers 21 and 23 which are characterized by the presence of hearths containing abundant burnt and charred faunal remains of ibex the fragmentation and burning rates as well as bone presence within hearths may suggest that they were used as a supplementary fuel resource following previous research on the suitability of bones as a supplement to firewood in hearth combustions a series of experiments are here presented using goat bones in consistency with the faunal record present at el esquilleu our experiments proved that small sized animal

upper pleistocene palaeoenvironmental change in eastern spain new pollen analytical data from cova beneito alicante abstract the results of a palynological investigation of the upper palaeolithic interval from the beneito cave southeastern spain are herewith considered in the context of results from a previous report on the underlying deposits two new percentage and concentration pollen diagrams with good correspondence are presented the upper palaeolithic sequence is dominated by poaceae chenopodiaceae and artemisia whereas arboreal pollen are less important mesophilous trees and mediterranean taxa show a constant presence but in low proportions the new data add support to the view that interpleniglacial development of mediterranean taxa was important in eastern spain while they were considerably reduced during upper pleniglacial times emphasis is placed on aridity as a limiting factor in influencing major vegetation changes in the area two additional topics are also presented they deal with the extrapolation of north european interstadials to mediterranean spain and the palaeoecological value of archaeopalynological records

mode of occupation of tabun cave mt carmel israel during the mousterian period a study of the sediments and phytoliths alternative modes of occupation of tabun cave during the deposition of the mousterian levels b and c have been proposed garrod bate 1937 excavations at the wady el mughara volume 1 oxford clarendon press interpreted the archaeological record of both levels as being indicative of domestic occupational activities jelinek et al 1973 palaeorient 1 151 183 proposed that the presence of articulated limb bones of dama mesopotamica in the level b sediments below the cave chimney indicated that the cave was used as a natural game trap they also noted that the white ash layers in level c extended across the whole cave and proposed that this was due to the burning of natural vegetation in the cave this study aims at clarifying the modes of occupation during these periods level b sediments closely resemble the terra rossa soil that is common in this region burning activity is inferred from charcoal fragments seen in thin sections a minor wood ash component is present based on the preponderance of phytoliths with a variable morphology as compared to those with a consistent morphology as well as phytoliths with shapes characteristic of those formed in wood and bark of local trees thus fires were produced in the cave during this period the cave may also have been used as a game trap level c is composed of multiple layers of brown black and white sediments micromorphology mineralogy and phytolith analyses all show that these layers are mixtures of terra rossa soil and ash with the latter being abundant in the white layers the phytoliths in these layers are derived almost entirely from wood and bark and not from grasses these observations are consistent with a domestic occupational mode 1999 academic press

reconstruction of historical sea surface temperatures using empirical orthogonal functions abstract studies of climate variability often rely on high quality sea surface temperature sst anomalies although the high resolution national centers for environmental prediction formerly the national meteorological center optimum interpolation oi sst analysis is satisfactory for these studies the oi resolution cannot be maintained before november 1931 due to the lack of satellite data longer periods of ssts have come from traditional analyses of in situ ship and buoy sst observations alone a new interpolation method is developed using spatial patterns from empirical orthogonal functions e0fs that is a principal component analysis to improve analyses of sst anomalies from 1950 to 1981 the method uses the more accurate oi analyses from 1982 to 1993 to produce the spatial eofs the dominant eof modes which correspond to the largest variance are used as basis functions and are fit in a least squares sense to the in situ data to determine the time dependence of each mode a complete field

northern iberian abrupt climate change dynamics during the last glacial cycle a view from lacustrine sediments abstract we present a palaeoclimatic reconstruction of the last glacial cycle in iberia ca 120 000 11 600 cal yrs bp based on multi proxy reconstructions from lake sediments with robust chronologies and with a particular focus on abrupt climate changes the selected lake sequences provide an integrated approach from northern iberia exploring temperature conditions humidity variations and land sea comparisons during the most relevant climate transitions of the last glacial period thus we present evidence that demonstrates i cold but relatively humid conditions during the transition from mis 5 to mis 4 which prevailed until ca 60 000 cal yrs bp in northern iberia ii a general tendency towards greater aridity during mis 4 and mis 3 ca 60 000 to 23 500 cal yrs bp punctuated by abrupt climate changes related to heinrich events he iii a complex highly variable climate during mis 2 23 500 to 14 600 cal yrs bp with the mystery interval mi 18 500 to 14 600 cal yrs bp and not the global last glacial maximum lgm 23 000 to 19 000 cal yrs bp as the coldest and most arid period the last glacial transition starts in synchrony with greenland ice records at 14 600 cal yrs bp but the temperature increase was not so abrupt in the iberian records and the highest humidity was attained during the allerod gi 1a to gi 1c and not during the bolling gi 1e period the younger dryas event gs 1 is discernible in northern iberian lake records as a cold and dry interval although iberian vegetation records present a geographically variable signal for this interval perhaps related to vegetation resilience

diagenesis in prehistoric caves the use of minerals that form in situ to assess the completeness of the archaeological record an interpretation of the archaeological record in particular that of a prehistoric cave site is complicated by the diversity of depositional and post depositional processes that affect the material deposited here we propose to use the authigenic minerals that form in situ within the cave sediments to reconstruct the ancient chemical environments in the sediments this can be done by experimentally determining the conditions under which each of the authigenic minerals are stable although this information is not available to date for minerals formed in a prehistoric cave we present calculated stability field data for the relevant minerals the results clearly demonstrate the feasibility of this approach this information particularly if based on measurements of real authigenic cave minerals will facilitate an assessment of the completeness of the cave archaeological record this is particularly important for determining whether or not the distributions of archaeologically important materials such as bones teeth plant phytoliths charcoal and ash reflect their original burial distributions or were altered as a result of secondary diagenetic processes

combustion structures of archaeological level o and mousterian activity areas with use of fire at the abric romani rockshelter ne iberian peninsula abstract the human use of fire generates a cultural sedimentary record that can be used to characterize prehistoric activity areas the aim of this paper is to develop a field guide for recognizing and describing combustion structures the use of fire as suggested by the results of ethnoarchaeological and prehistoric archaeological studies has served as the foundation for the analytical design of the field observations of the combustion structures at the abric romani rockshelter flat and concave combustion structure types have been uncovered in archaeological level o the systematic recording of the sedimentary and dimensional attributes of the combustion structures can be used as empirical evidence with which to characterize the use of fire differences in the use of fire represent a significant finding in the cultural repertoires of neanderthals recognizing and recording the specific organizational patterns of these activity areas such as fire use in sleeping and resting activity areas indicate the definitive emergence of home bases in the spatial record of the living floors of the archaic human groups

sediments exposed to high temperatures reconstructing pyrotechnological processes in late bronze and iron age strata at tel dor israel many of the sediments analysed from tel dor israel show structural alterations indicating that they were exposed to high temperatures this observation is consistent with the abundant evidence for use of pyrotechnology from the earliest exposed middle bronze age strata through the roman period such structurally altered sediments may well represent one of the more widespread and durable records of pyrotechnology and as such could be invaluable for reconstructing past human activities the specific aims of this research are therefore to develop the means for identifying local sediments that were altered by different pyrotechnological activities and to elucidate the varying circumstances whereby sediments were exposed to high temperatures in a late bronze and iron age 1 section we first characterize natural sediments sampled on and in the proximity of the tell and monitor their transformations due to exposure to high temperatures in an oven and in open fires focusing in particular on the transformations of the clay mineral components of mud brick materials the analytical techniques used include micromorphology fourier transform infrared spectrometry ftir x ray powder diffractometry xrd and x ray fluorescence xrf spectrometry using the temperature calibrated data we confirm that large volumes of sediments at tel dor were exposed to high temperatures in area g we identify three fundamentally different ways that heat affected sediments were produced and accumulated 1 inthelatebronzeage phases11e12 thesedimentswereheatedtotemperaturesbetween800and900 candwerethendeposited in the area under investigation a plausible scenario is that these sediments were exposed to heat from ovens or kilns 2 during the early iron age phase 10 the heat affected sediments heated above 1000 c formed in close association with casting pits for the working of copper containing bronze objects 3 duringphase9oftheironage heat affectedsedimentswereproducedinsituatthislocationduetoamajorconflagration the temperatures reached around 1000 c this study shows that analysis of high temperature exposed sediments may be an invaluable means of reconstructing fire associated activities even when the actual installations have not been identified during the excavation or were not preserved

seasonal dependence of surface wind stress variability on sst and precipitation over the tropical pacific the dependence of interannual variability of surface zonal and meridional wind stresses x and y on sea surface temperature sst and precipitation over the tropical pacific is examined using observed data a strong seasonality in the dependence is found in january the largest sst and precipitation anomalies are located in the central to eastern and central tropical pacific respectively x anomalies in the southern central tropical pacific and y anomalies in the northern tropical pacific are highly correlated to both the sst and precipitation anomalies in contrast during july the largest sst and precipitation anomalies are located at the eastern and western tropical pacific respectively east of the dateline x anomalies present little dependence on the sst anomalies west of the dateline x anomalies depend strongly on the precipitation anomalies that are not linked to the leading modes of sst

human impact around settlement sites a phytolith and mineralogical study for assessing site boundaries phytolith preservation and implications for spatial reconstructions using plant remains abstract defining the extent of human activity around settlement sites is of particular significance in archaeology as it may define peripheral activity areas and thus the site s boundary in near eastern archaeology site boundaries are usually defined by the presence of architectural and other macroscopic archaeological remains here we use the phytolith concentrations and morphotype assemblages as well as changes in the mineralogical composition of the sediments in and around the small iron age site of izbet sartah in central israel to determine the site boundaries the site has a shallow stratigraphy and highly bioturbated sediments coincidental changes in the clay quartz ratio and phytolith concentrations define the boundary between high and low impact anthropogenic activities this boundary is generally some 20 m away from the architectural remains in addition we note that the phytoliths in the site s core show clear evidence of having been affected by chemical dissolution i e diagenesis while those in the vicinity of the site s boundary have undergone severe diagenesis these observations indicate that phytolith diagenesis will affect site boundaries determination as well as phytolith based reconstructions of activity areas we propose that phytolith preservation depends on the initial amount of available silica the depth of burial with respect to the active root area of modern vegetation and the presence of fresh phytoliths in the soil

stress strain response of cold lake oil sands the stress strain response of cold lake oil sands at confining stresses and temperatures up to 18 mpa and 200 c respectively was studied in a triaxial apparatus using 89 mm full diameter cores

mobilized strength components of athabasca oil sand in triaxial compression dense uncemented athabasca oil sand specimens exhibit unusually high peak strength dilation with severe softening and residual strength in drained triaxial compression tests computer tomography

stability of phytoliths in the archaeological record a dissolution study of modern and fossil phytoliths opaline phytoliths are important microfossils used in archaeological and ecological research relatively little is known about the stability of phytoliths after burial under alkaline ph conditions they can dissolve and mechanical disturbances can cause a loss of their more delicate appendages here we present an experimental study of phytolith stability combination of solubility and abrasion modern and fossil phytoliths were extracted from wheat using new methods to minimize dissolution and by burning in an oven these assemblages were placed in a solution buffered to ph 10 and maintained under constant temperature and shaking conditions the silicon concentrations in the solution were monitored once a week for 5 weeks the phytolith morphologies in each assemblage were determined at the outset of the experiment and after 5 weeks the results show that there are differences in stability between various assemblages modern inflorescence wheat phytolith assemblages are more unstable than those from leaves stems burnt assemblages are less stable than unburnt assemblages and a fossil phytolith assemblage about 3000 years old is more stable than the modern wheat assemblages the results also show that individual phytolith morphotypes have different stabilities and as a result of dissolution and abrasion some morphotypes may resemble others this study further shows that archaeological and or paleo environmental interpretation of phytolith assemblages may change with the assemblage s state of preservation

quantitative phytolith study of hearths from the natufian and middle palaeolithic levels of hayonim cave galilee israel abstract a study of the mineralogy and phytolith assemblages of hearths and their associated sediments in hayonim cave israel shows that wood ash is a major component of the sediments of both the natufian approximately 12 000 bp and the mousterian deposits approximately 100 to 250 000 bp interestingly phytolith analyses show that in the natufian deposits grasses are the second most abundant form of vegetation preserved whereas in the mousterian deposits leaves of dicotyledonous plants are the second most abundant form of vegetation preserved significant differences were repeatedly observed in phytolith assemblages from closely associated but different stratigraphic layers showing that vertical mixing of intact sediments is not intensive and that there was a diverse input of vegetation over relatively short time periods no consistent differences were observed in the mineralogy and the phytolith assemblages between hearths and their associated sediments both contain abundant ash components this study demonstrates that quantitative analyses of phytoliths together with mineralogical analyses can provide much information on the use of plants for fuel and other purposes by the cave occupants

strain induced anisotropy in fabric and hydraulic parameters of oil sand in triaxial compression dense locked athabasca oil sand specimens were tested in drained triaxial compression with lubricated ends at confining pressures of 5 750 kpa computer tomography and scanning electron microscopy imaging techniques were used to examine the microstructural features interlocked structure grain fabric and rearrangement inside and outside shear bands of the intact and sheared specimens the average hydraulic radii and tortuosity along three principal directions were also measured using thin section imaging and electrical resistivity measurement methods it was found that changes in fabric and hydraulic parameters of oil sand in triaxial compression are highly inter related intrinsic and induced anisotropies in permeability were observed key words oil sand fabric strain induced anisotropy permeability tortuosity dilatancy

microstratigraphy and diagenesis at the upper pleistocene site of esquilleu cave cantabria spain ftir and soil micromorphology were applied to selected sediments from the archaeological deposit of esquilleu cave a late middle palaeolithic site in cantabria spain the main goal was to assess the integrity of the archaeological record before continuing with further excavation and research at the site field observations and previous sedimentological studies point to diagenetic alteration of part of the deposit but the extent and precise nature of such processes had not been established the results show that the upper layers are composed of fresh elements and have not undergone diagenetic transformations although their components have been physically disturbed by cryoturbation the rest of the deposit is well preserved with mild phosphatization due to partial dissolution of bone and calcitic ash contained in the sediment and compression from trampling further excavation is necessary to have a more complete picture of the taphonomic processes taking place at the site

rapid phytolith extraction for analysis of phytolith concentrations and assemblages during an excavation an application at tell es safi gath israel abstract a rapid phytolith extraction procedure is described that allows phytolith concentrations and morphotype assemblages to be analyzed within hours this procedure enables the results of these analyses to be used during an archaeological excavation in order to better understand how plants were used the new procedure was tested using a standard phytolith extract and two experimental phytolith sediment blends and found to be both accurate and precise the reliability of partial slide counting was evaluated and found to be as accurate and precise as existing phytolith quantification methods the new extraction and counting procedures were applied to an archaeological site tell es safi gath israel the results demonstrate how information on phytolith concentrations in sediments that are available from one day to the next can be used during an excavation to more effectively document the local features of interest and obtain better information

evidence for the repeated use of a central hearth at middle pleistocene 300 ky ago qesem cave israel abstract a major debate in prehistory revolves around the time and place of the earliest habitual use of fire and the hominin species responsible for it here we present a newly discovered hearth at qesem cave israel that was repeatedly used and was the focus of hearth centered human activities as early as three hundred thousand years ago the hearth identified based on mineralogical and microscopic criteria contains two superimposed use cycles each composed of shorter episodes possibly the earliest superimposed hearth securely identified to date the hearth covers ca 4 m 2 in area making it a uniquely large hearth in comparison to any contemporaneous hearth identified thus far possibly indicating it has been used by a relatively large group of people in addition the hearth is located in the center of the cave and is associated with butchered animal remains and a dense flint assemblage the flint assemblage indicates spatially differentiated meat cutting and hide working activity areas the central location of the hearth within the cave and the activities associated with it may reflect an embedded perception of space organization of the qesem cave inhabitants since fire was habitually used throughout the 420 200 ky sequence of qesem cave where preservation conditions are alike throughout we suggest that this unique hearth may reflect a development in nature and most probably in the intensity of fire use in qesem cave from ca 300 ka ago onwards

distinguishing between calcites formed by different mechanisms using infrared spectrometry archaeological applications infrared spectrometry is a well established method for the identification of minerals due to its simplicity and the short time required to obtain a result it can be practiced on site during excavation using portable infrared spectrometers however the identification of a mineral may not be sufficient for example a lime plaster floor and a crushed chalk surface have a similar appearance and are composed of the same mineral calcite here we exploit differences in the infrared spectra of geogenic biogenic and pyrogenic calcites for the identification of each calcite type the infrared calcite spectrum has three characteristic peaks in the region of 400 4000 cm 1 designated 2 3 and 4 when a calcite sample is ground as part of the measurement preparation procedure some grinding dependent changes will be revealed in the infrared spectrum with additional grinding the 3 peak narrows and the heights of the 2 and 4 peaks decrease when both are normalized to the 3 height by plotting the normalized heights of the 2versus the 4 of several grindings of the same sample a characteristic trend line is formed for each calcite type the trend lines of geogenic calcites have the shallowest slopes and highest 4 values when compared to pyrogenic calcites which can be further divided to ash and plaster mortar samples this method can assist in distinguishing between the various calcites and provide insights into homogeneity and preservation state of the calcitic materials in question

on the role of sea surface temperature gradients in forcing low level winds and convergence in the tropics abstract we examine the importance of pressure gradients due to surface temperature gradients to low level p 700 mb flow and convergence in the tropics over time scales 1 month the latter plays a crucial role in determining the distribution of cumulonimbus convection and rainfall our approach is to consider a simple one layer model of the trade cumulus boundary layer wherein surface temperature gradients are mixed vertically consistent with ecmwf analyzed data the top of the layer is taken at 700 mb the influence from higher levels is intentionally suppressed by setting horizontal pressure gradients and frictional stresses to zero at the top of the layer horizontal convergence within the layer is taken up by cumulonimbus mass flux however the development of the cumulonimbus mass flux is associated with a short relaxation time o hr roughly the development time for such convection during this short time horizontal convergence acts to redistribute mass so as to reduce horizontal pressur

phytolith and ftir studies applied to combustion structures the case of the middle paleolithic site of el salt alcoy alicante abstract the combination of phytolith and ftir analyses is a powerful tool to investigate the use of fire by past human populations here we apply these methods to study the hearths of the subunit xb at the middle palaeolithic site of el salt in alcoi el salt is characterized by recurrent neanderthal occupations that produced a succession of combustion structures and other anthropogenic remains using ftir analysis we have been able to detect the presence of ashes thermally altered clay and phosphatic minerals in the sediments phytolith results point to the use of wood as fuel in subunit xb however most of the phytoliths have been deposited in the site by natural agents probably in the form of bird guano characterized by the presence of distinctive phytoliths of seed coats from celtis sp differentiating between natural and anthropogenic deposited phytoliths is essential to evaluate the impact produced by human activities in the archaeological sediments

phytolith evidence for hearths and beds in the late mousterian occupations of esquilleu cave cantabria spain esquilleu cave site has provided a moderately well preserved archaeological cave deposit from the late pleistocene in the cantabrian area phytolith quantification identification and determination of the refractive index have been carried out together with ftir analyses from sediment samples collected in the profile the comparison of the data obtained with the previous micromorphological results allows us to make inferences about the site formation processes and the neanderthals use of the cave phytolith results show the presence of grass leaves nearby the hearth suggesting the repetitive existence of a bedding zone on the same area neanderthal behavioral patterns should be revised on the light of high resolution analyses since diagenetic processes can obscure the existence of differentiated activity areas in the site

formation processes through archaeobotanical remains the case of the bronze age levels in el mirador cave sierra de atapuerca spain el mirador site has a sequence formed by burnt dung resulting from pastoral activities during the bronze age and the neolithic period because there is a high sediment variation in the profile facies descriptions were used to guide the archaeologists in their work paleobotanical and mineralogical analyses were used to describe and understand the formation of the facies from the mir 4 level furthermore the paleobotanical results serve to reconstruct the landscape in atapuerca during the bronze age most seeds recovered are from triticum aestivum durum but other cereals and also leguminoseae and fruits have been identified charcoal analysis has yielded mainly deciduous and evergreen quercus pollen analysis has revealed a low arboreal cover with pinus quercus and riverside trees most of the pollen record corresponds to herbs such as poaceae and asteraceae all these results indicate a mosaic of different biota with forest pastureland and cultivated fields near the site most of the phytoliths come from the leaves and stems of festucoid grasses however there are some differences in the phytolith type and number the amount of faecal spherulites the mineralogical composition and the percentage of multicellular structures that indicate that not all the facies in the site have been formed in the same way thus the work carried out has demonstrated that some facies are related more to agricultural activities than to pastoralism activities and that other facies have been affected by incipient diagenetic processes

bat guano and preservation of archaeological remains in cave sites the formation of authigenic minerals in cave sediments can be used to reconstruct the paleochemical conditions that prevailed in the past and in this way to assess the completeness of the archaeological record previous studies indicated that the major driving mechanisms for chemical diagenesis in prehistoric caves that result in the formation of authigenic minerals are the degradation of bat guano and the local hydrology we therefore investigated contemporary bat guano deposits in caves and the sediments directly below such deposits the emerging patterns show that the formation of authigenic minerals occurs under acidic conditions within tens of years the availability of phosphate al k and fe increases with increasing organic matter degradation while the availability of nitrogen and sulfur decreases insectivorous bat guano contains larger amounts of phosphate and is more acidic than fruit bat guano in the first stages of diagenesis micro chemical environments form within the degrading bat guano that result in the formation of a wide variety of authigenic minerals during advanced stages of diagenesis steady state conditions are achieved resulting in authigenic mineral assemblages being dominated by one mineral type at the same locale this is reminiscent of known distributions of authigenic minerals in prehistoric cave sediments under the acidic conditions produced by degrading bat guano deposits calcareous artifacts and bones are not expected to persist for long periods of time unless there is a lot of calcite in the sediments that could buffer the sediment water ph guano itself is not likely to be preserved periods of cave abandonment can be inferred from the presence of authigenic minerals in the sediments as it is during these times that bats mainly occupy the cave the occurrence of certain authigenic minerals in open air sites may serve as evidence for areas rich in organic matter containing phosphate i e animal enclosures latrines sewers trash pits and or bones as the degradation process is rapid the use of authigenic minerals to identify these loci is relevant to almost all archaeological as well as historical sites

quantifying the evolution of soil fabric during shearing using scalar parameters the packing density of a soil is typically described in terms of the scalar parameters void ratio specific volume or porosity within a critical state soil mechanics framework the response of a sand is considered to depend on its state that is the combination of void ratio and effective stress when soil is considered from a particle scale perspective the packing density is often described using the coordination number cn that is the average number of contacts per particle using particles with simple geometries discrete element method dem simulations photoelastic tests and experiments on analogue soils e g glass ballotini have all demonstrated a correlation between cn and mechanical response this study investigates whether these correlations apply to real soils using direct measurement of the fabric via micro computed tomography micro ct a variety of scalar fabric descriptors was measured during the triaxial compression of both intact and reconstituted reigate sand samples while ea

phytoliths in the middle palaeolithic deposits of kebara cave mt carmel israel study of the plant materials used for fuel and other purposes abstract kebara cave israel is a well studied archaeological site it contains abundant visible hearths ash derived minerals are a major component of the mousterian sediments and are present in varying states of preservation furthermore archaeobotanic information is available from charred remains kebara cave is thus an ideal location to study the potential of phytoliths to provide information on the mode of fire use in the cave to assess the input of other plant materials as well as to determine the effects of diagenesis on phytolith preservation twenty samples were analysed in terms of their mineralogy phytolith contents per unit weight of acid insoluble fraction and phytolith morphologies in general the preservation of the phytoliths is good except for the two samples in which the mineral component associated at present with the phytoliths is mainly ash derived calcite the cave sediments contain about ten times more phytoliths than those present in the four samples analysed from outside the cave the major source of plant material input into the cave is clearly from the wood and bark used for the fuel for fires the grass phytoliths present in the samples are also thought in part to have been brought into the cave associated with the wood bark fuel sediments from the hearths as well as those between the hearths contain abundant wood bark phytoliths the two samples of the latter contain appreciable amounts of phytoliths not known to be present in wood and bark as do other hearth derived samples plant materials other than those used as fuel were thus also brought into the cave this study shows that phytolith analyses in conjunction with detailed mineralogical stratigraphic archaeobotanic and field information can provide a more complete understanding of the use of plant materials in prehistoric caves for fuel

the earliest evidence of hearths in southern europe the case of bolomor cave valencia spain abstract most researchers agree about the importance of the fire during the pleistocene the controlled use of fire could allow advances in the ways of life not only for its value as a constant source of light and heat but also because it contributed to the processing of food to warding off the carnivores and especially to human socialization as fire can be understood as a focus of concentration of activities and structuring of inhabited space apart from the many utilities that the hearths may have had during the pleistocene this research does not allow specification of the chronological and geographical context of the first controlled use of fire from this perspective the present study contributes to this discussion with the data from bolomor cave valencia spain this site contains a sedimentary deposit composed of seventeen stratigraphical levels ranging from mis 9 to mis 5e c 350 100 ky the stratigraphical series presents clear evidence of the controlled and reiterative use of fire the used analytic techniques have confirmed the presence of hearths at levels ii iv xi and xiii of the site this paper discusses the hearths from level xiii chronologically located in mis 7c with an amino acid racemization aar date of 228 53 ky these combustion structures are the most ancient known today not only at bolomor cave and in spain but also in southern europe from this perspective the aim of this study is to make known the hearths from level xiii of bolomor cave and to provide data that contribute to the general debate about the presence knowledge and use of fire in the european middle pleistocene

extended wind stress analyses for enso abstract surface wind stresses are fundamental to understanding el nino yet most observational stress products are too short to permit multidecadal enso studies two exceptions are the florida state university subjective analysis fsu1 and the ncep ncar reanalysis ncep1 which are widely used in climate research here the focus is on the aspects of the stress most relevant to enso namely the climatological background anomaly spectrum response to sst changes subannual noise forcing and seasonal phase locking and how these differ between fsu1 and ncep1 over the tropical pacific for 1961 99 the ncep1 stress climatology is distinguished from fsu1 by weaker equatorial easterlies stronger off equatorial cyclonic curl stronger southerlies along the peruvian coast and weaker convergence zones with weaker seasonality compared to fsu1 the ncep1 zonal stress anomalies x are weaker less noisy and show less persistent westerly peaks during el nino events ncep1 also shows a more stationary spec

plio pleistocene macroplant fossil remains and phytoliths from lowermost bed ii in the eastern palaeolake margin of olduvai gorge tanzania abstract fossil macroplants and phytoliths occur in the sediments of the palaeoanthropological site of olduvai gorge northern tanzania current research on hominin land use in the basin during the plio pleistocene has a strong palaeoenvironmental emphasis on the palaeovegetation in particular the occurrence of macroplants and phytoliths at olduvai and their usefulness and reliability for palaeovegetation interpretation are assessed here for the first time modern reference collections from analogous environments have been established and used to identify the fossil taxa from the eastern palaeolake margin of lowermost bed ii as the test case for very detailed spatially and temporally constrained vegetation reconstruction fourier transform infrared spectrometry ftir analysis was used to identify the minerals of the fossil sediments modern plants produce more phytoliths than are preserved in the fossil soils but there were sufficient numbers to show diverse and changing vegetation over short time periods silicified macroplant fragments of sedge culms and dicot stems occur with phytoliths but do not always represent the same plant taxa a more complex flora was shown when using both forms of fossil plants during lowermost bed ii times at the locality of flkn monocots and dicots occurred indicating the presence of marshland and grassland after the deposition of tuff if at vek the phytoliths indicate a shift in dominance from dicots to monocots to a mixture of the two and including palms at hwkee initially palms dominated then there was a mixture of palms grasses and dicots the vegetation at mck comprised dicots monocots sedges and grasses this detailed vegetation data complements the more broad scale vegetation interpretations that have been deduced from the pollen isotopes and faunal data sets