abrupt mousterian aurignacian boundary at c 40 ka bp accelerator 14c dates from l arbreda cave catalunya spain abstract the cultural transition from mousterian to aurignacian is abrupt at l arbreda cave and occurs within a homogeneous sedimentary unit with no visible lithologic changes fragments of milligram size charcoal were collected immediately above and below the cultural boundary for radiocarbon dating by accelerator four charcoal fragments from the lowest basal aurignacian level yielded dates of 37 7 1 0 37 7 1 0 39 9 1 2 and 38 7 1 2 ka bp average 38 5 1 0 ka bp these ages are similar to three dates from the same cultural horizon at el castillo cave in cantabria and both sets of dates are significantly older than the earliest reported for the aurignacian in the aquitaine and in other parts of central and western europe the dates are in accord with similarly early dates for aurignacian in bulgaria and suggest that appearance of aurignacian peoples is synchronous across europe three fragments from the uppermost mousterian level yielded dates of 39 4 1 4 34 1 0 75 and 41 4 1 6 ka bp discounting the spurious 34 1 ka bp result these dates are slightly older average 40 4 1 4 ka bp but overlap with counting error the basal aurignacian dates the data show that the transition from mousterian to aurignacian was chronologically abrupt at this location these results strongly support the replacement hypothesis

hafted armatures and multi component tool design at the micoquian site of inden altdorf germany abstract excavation of the micoquian site inden altdorf weisweiler 124 near the former german capital bonn in western germany has revealed the first valid open site habitation features with hut like structures and associated hearths for the middle palaeolithic in central europe it has been dated to the eemian interglacial ois 5e a warm interglacial between 128 and 115 ka bp various wear traces and especially organic residues have been detected on a large number of stone tools using microscopic use wear analysis of lithics recovered from the site a multi level analysis developed through an experimental framework and archaeological study using optical light microscopes scanning electron microscopes and energy dispersive x ray microprobes identified the adhering residues as birch pitch birch pitch is the oldest synthetically produced material and was used as an adhesive to attach lithic implements to wooden shafts while such hafting technology is commonly associated with modern humans in the upper palaeolithic the birch pitch residues found on the micoquian tools of inden altdorf suggest that hafting technologies and the frequent use of multi component tools already existed in the middle palaeolithic c 120 ka bp in central europe

formation of mud clast breccias and the process of sedimentary autobrecciation in the hominin bearing homo naledi rising star cave system south africa unconsolidated mud clast breccia facies in the hominin bearing homo naledi rising star cave cradle of humankind south africa are interpreted to have formed through a process termed sedimentary autobrecciation in this study this process by which most of the angular mud clast breccia deposits are thought to have formed autochthonously to para autochthonously via a combination of erosion desiccation diagenesis and microbial alteration of laminated mud deposits is thought to have taken place under relatively dry i e non flooded conditions inside the cave subsequently gravitational slumping and collapse was the dominant mechanism that produced the mud clast breccia deposits which commonly accumulate into debris aprons the mud clast breccia is typically associated with micro mammal fossils and is a common facies throughout the cave system occurring in lithified and unlithified form this facies has not been described from other cave localities in the cradle of humankind additionally sedimentary autobrecciation took place during the deposition of some of the fossils within the rising star cave including the abundant homo naledi skeletal remains found in the dinaledi subsystem reworking of the mud clast breccia deposits occurs in some chambers as they slump towards floor drains resulting in the repositioning of fossils embedded in the breccias as evidenced by cross cutting manganese staining lines on some homo naledi fossil remains the formation of the unlithified mud clast breccia deposits is a slow process with first order formation rates estimated to be ca 8 x 10 4 mm year 1 the slow formation of the unlithified mud clast breccia facies sediments and lack of laminated mud facies within these deposits indicates that conditions in the dinaledi chamber were probably stable and dry for at least the last ca 300 ka meaning that this study excludes homo naledi being actively transported by fluvial mechanisms during the time their remains entered the cave

trace fossils biology and taphonomy 1990 special topics in palaeontology 3 280 pp e17 95 pbk e40 00 hbk unwin hyman london isbn 004445 6867 pbk 3035 hbk

the calcarenite di gravina formation in matera southern italy new insights for coarse grained large scale cross bedded bodies encased in offshore deposits excellent outcrops of the upper pliocene lower pleistocene calcarenite di gravina around matera southern italy provide continuous exposure of coarse grained clastic basin margin shoreline to offshore facies among these facies the most conspicuous and volumetrically important are the transition slope deposits that form large scale high angle cross bedded lithosomes these are laterally extensive parallel with the paleoshoreline and show seaward progradation we interpret them to represent avalanches of sediment swept out onto a depositional slope below wave base from the shoreface zone by storm waves and wind driven currents three types of building blocks are recognized based on bedding patterns and facies architecture embryonic parasequences mature parasequences and simple sequences parasequences formed during stillstands of sea level and simple sequences during high frequency cycles of relative change of sea level these building blocks are stacked in a backstepping configuration and onlap onto cretaceous limestone substrate backstepping is believed to be due to a tectonically forced transgression that is punctuated by high frequency cycles of sea level modern analogs for these building blocks are the holocene prograding prisms detected in high resolution seismic lines of the mediterranean shelves the reflection patterns of these seismic units resemble the bedding architecture of the matera simple sequences and parasequences and show similarities of shape size position and orientation of coastal setting and direction of progradation comparison of the holocene prisms and the pliocene pleistocene accretional units in matera indicates that they may represent the same begin page 662 genetic process progradation of clastic prisms below the wave base level the matera accretional units also show similarities with other examples of laterally extensive large scale cross bedded sand bodies encased in offshore deposits such as some sandbanks differentiating between these laterally extensive and seaward prograding cross bedded sand bodies and some coarse grained gilbert type deltas is difficult however if interpretations are based only on two dimensional 2 d outcrops in dip section without high resolution data it is also difficult to distinguish between transition slope and prograding shoreface lithosomes this difficulty may be acute where only seismic or well log data are available however certain other architectural characteristics such as stacking and preservation of facies belts and position of bounding surfaces as well as differences in associated sedimentary structures and fossil content may be used for interpretation the matera example provides a mechanism for emplacement in offshore settings of elongate and strandline parallel sand and gravel deposits that prograde seaward and that preserve a coarsening upward internal succession this article offers an interpretation for other ancient examples of large scale cross bedded lithosomes encased in offshore deposits

the interpretation of stratified sites a view from underground abstract this paper reports on an experiment designed to study the role of trampling in the vertical dispersal of artifacts in the soil and in the mixing of originally separate sets of materials the experiment is part of a study of the archaeological stratigraphy and patterns of site use at a large stratified cave in southern france the experiment was designed to replicate conditions prevailing at the cave the results strongly suggest caution in the interpretation of living floors and stratified assemblages in sandy deposits

dansgaard oeschger and heinrich event imprints in alboran sea paleotemperatures past sea surface temperature sst evolution in the alboran sea western mediterranean during the last 50 000 years has been inferred from the study of c37 alkenones in international marine global change studies md952043 core this record has a time resolution of 200 years allowing the study of millennial scale and even shorter climatic changes the observed sst curve displays characteristic sequences of extremely rapid warming and cooling events along the glacial period comparison of this alboran record with 18o from greenland ice greenland ice sheet project 2 core shows a strong parallelism between these sst oscillations and the dansgaard oeschger events five prominent cooling episodes standing out in the sst profile are accompanied by an anomalous high abundance of neogloboquadrina pachyderma sinistral which is confined to the duration of these cold intervals these features and the isotopic record reflect drastic changes in the surface hydrography of the alboran sea in association with heinrich events hl 5

a chronicle of crisis the late mousterian in north iberia cueva del esquilleu cantabria spain abstract during the last decades the cantabrian region has become one of the zones of greater interest in the study of the final mousterian on the european scale the particular ecological and physiographic conditions of this region provide an especially attractive picture for analyzing the advanced moments of this period almost all the mousterian levels of cantabrian sites are dated to the later part of wurm ii as occurs in some other european regions close to 35 ka bp the esquilleu sequence expresses a process of change in archaeological record and probably in the subsistence strategies this late occupation extends through the h4 cold event and the interglacial to wurm iii between level vif 34 3 ka bp approx ams and level iv 22 8 ka bp approx ams all the archaeological evidence non selective and directly adjacent to the river catchment limited technical investment with fast discoid production mainly points but objectively indeterminate from a morphological point of view lithic and even microlithic production and their interpretation in a spatial contextual perspective high fragmentation of the chaine operatoire between the river and the cave would indicate changes in the site function within an articulated network archaeologically the change in the significance of el esquilleu intervals is evident the raw material catchment analysis indicates a much more fuzzy relationship of the site in relation to the environment esquilleu would have ceased functioning as a place of integration of elements of the territory there is no evidence of transport or territorial relationship defined between sites another point for reflection is that in the esquilleu sequence different production methods and the archaeological evidence interpretation can be grouped easily into discrete sets the lower interval is technically variable probably representing the time with more functional complexity in the cave subsequently the quina levallois discoid and final intervals occur archaeological evidence of these higher levels including the technical domains changes gradually with clearly recognizable features along the sequence these common elements sometimes very slightly detected selected lithologies very small size discoid productions pointed morphologies from diametric fractures would refer to a cultural continuity in the communities that inhabited the esquilleu region for millennia

u series dates for stalagmitic flowstone e riss wurm interglaciation at grotte du lazaret nice france abstract several samples of stalagmitic flowstone ensemble e at grotte du lazaret nice france were dated by u series isotopes the results show that this speleothem began to grow about 130 000 yr b p and continued to about 70 000 yr b p coinciding almost exactly with the last interglaciation isotope stage 5 even though ensemble e is not in direct stratigraphic relation with the cave deposits this study shows that the acheulian artifacts industry and fauna within lazaret are older than the riss wurm interglaciation

fluvial changes of the guadalquivir river during the holocene in cordoba southern spain this research was funded by a grant from proyectos de cordoba siglo xxi coordinated by prof r jose roldan canas universidad de cordoba

palaeoflood and floodplain records from spain evidence for long term climate variability and environmental changes abstract palaeoflood chronologies from seven spanish river basins and floodplain aggradation chronologies from thirteen rivers are analysed these fluvial records were divided in to two sub sets namely atlantic 10 ka record and mediterranean 3 ka record river basins which represent distinct modern hydroclimatic conditions in atlantic basins floods result from intense widespread rainfalls associated with atlantic frontal systems transported by westerly airflow mediterranean river flooding is related to heavy rainfall induced by mesoscale convective systems mcss during autumn months evidence from radiocarbon dates in slackwater flood deposits shows six periods of flood clusters at 10 750 10 240 9550 9130 4820 4440 2865 2350 960 790 and 520 290 cal bp despite the different flood producing weather conditions in atlantic and mediterranean rivers the radiocarbon sample clusters overlap and indicate changes in large scale atmospheric circulation and climatic conditions in the iberian peninsula comparison with proxy records of mean temperature for the northern hemisphere demonstrates a relationship between the period of slackwater flood deposition and cold climatic phases e g the 2650 yr bp climatic event or ad 1590 1650 period of the little ice age radiocarbon dates from aggraded floodplain sediments were clustered at 2710 2320 2000 1830 and 910 500 cal bp the first cluster period is in phase with the timing of slackwater deposition whereas the third 910 500 cal bp occurs in between two periods of increased flood frequency as indicated by the palaeoflood and documentary flood records it is argued that the 910 500 cal bp floodplain aggradation period reflects the first post roman evidence of environmental change related to generalised land use changes at the catchment scale which produced high sediment load transported to overbank areas during high flows

challenges for a cross disciplinary geoarchaeology the intersection between environmental history and geomorphology abstract geoarchaeology is a growing subfield of cross disciplinary research at the intersection between geomorphology environmental history and archaeology this prospective essay does not aim to analyze the nature or evolution of geoarachaeology or to review available techniques and methods instead it addresses challenges exciting challenges confront geoarchaeology in the form of persistent problems that demand satisfactory solutions despite improving skills and innovative technologies drawing from the full record of human history a number of practical issues can be highlighted to explicate these challenges 1 open air archaeological sites are the main object of study for the early to mid pleistocene even though they represent open systems that raise fundamental questions about archaeo taphonomic integrity how were sites buried and then modified by selective preservation horizontal or vertical disturbance and the role of carnivores is it possible to determine the degree to which such sites accurately record prehistoric human behavior prior to the late pleistocene when hearths and living structures lend better definition to occupation surfaces can non primary open air sites also shed light on human activities and environmental history 2 cave sites have long been favored by archaeologists because of the impression that they represent relatively complete and undisturbed archaeostratigraphic sequences but serious problems also exist here in regard to the nature of accumulation and the sources of mineral and biogenic sediments in what were open systems liable to disturbance despite comparatively low energy processes 3 less familiar are urban and other architectural sites where processes of formation and degradation mimic natural sedimentation and erosion such a geoarchaeology can be highly informative for urban processes demographic cycles or the intersection between sites and their surrounding landscapes 4 spatial components of geoarchaeological research need more systematic consideration for locational strategies and with an appreciation that site presence or absence allows a more dynamic modeling of settlement and procurement strategies 5 regional settlement expansion and contraction may also inform on mosaic evolution or pleistocene dispersals including the out of africa hypothesis 5 finally multiple themes connected with environmental degradation during holocene times may open new windows to examine specific problems by objective criteria so contributing to a wider academic discourse about long term trends the interfingering of climatic and land use factors in cause and effect dilemmas or the construction of future scenarios in an era of accelerating planetary change the focus of archaeology is shifting to later ranges of prehistory so that geoarchaeologists now have a mandate to engage more directly with urban spatial and degradation issues this should be met with a broader and more inclusive agenda one that optimizes on expertise with historical geomorphology and environmental history but in collaboration with archaeologists and other social scientists that would sustain a more prominent role for geoarchaeology in the university curriculum

230 th 234 u age of a mousterian site in france pech de l aze is a group of caves and rock shelters near sarlat in the dordogne district of south west france in the cave pech i there occurs a remanent of breccia containing mousterian middle palaeolithic artefacts of denticulate and typical varieties overlying a travertine layer we have used the 230th 234u dating method to determine the age of this travertine 123 15 kyr this age is consistent with deposition of this travertine during isotope state 5e the warmest substage of the last interglacial we show here that this result is consistent with geological and palaeontological estimates of the age of sediments filling the cave1

turia river delta and coastal barrier lagoon of valencia mediterranean coast of spain geomorphological processes and global climate fluctuations since iberian roman times abstract extensive drillings and 31 new c 14 datings were used to establish the geomorphological evolution of the turia river delta and coastal barrier lagoon system of valencia spain over the last three millennia integration of geomorphological stratigraphic malacological sedimentological and geoarchaeological data enables us to relate river turia avulsions and alluvial episodes to the development of coastal spits and barriers geomorphological changes in the study area may also be associated with global climate events sea level fluctuations or anthropogenic periods in the turia catchment six phases may be differentiated 1 a major early alluviation phase during the iberian period when the turia river ran to the north of the coastal plain and sand spits closed the valencia open lagoon environments forming a permeable barrier 2800 bp to 2300 bp approximately 2 an avulsion phase of the turia river to the south at the end of the roman period 4th century ad 3 formation of a more advanced spit just behind the most recent barrier during the late antique little ice age lalia visigothic period 4 a flood period of high magnitude with coarser sediments throughout the medieval climate anomaly mca 11th century ad when la punta meridional deltaic ridge developed which can be related to beach ridge closing and marine isolation of the valencia lagoon around the 12th century 5 important river alluviation and growth of the recent coastal barrier favoured by turia channel changes during the middle ages in the early little ice age lia 6 rapid coastal progradation and decline in salinity in the valencia lagoon between the maunder sunspot minimum mm and the end of lia

a mosaic of change the middle upper paleolithic transition as viewed from new mexico and iberia abstract from the cultural archeological perspective there is growing evidence that there was not only considerable variability but also significant change within the block of time that prehistorians call the middle paleolithic mp this was not a period of stasis and thus the actors homo sapiens neanderthalensis in europe were quite capable of adapting to new environmental circumstances in sensu lato likewise the so called upper paleolithic up was a cultural monolith neither in time nor in space in particular humans had to react in significant ways to the environmental crisis of the last glacial maximum that began some 20 14 c kyr after the transition to modernity adaptation is a continuously ongoing process sometimes slow but at other times fast the complementary opposition that has been set up by archeologists between the mp and the up obscures the considerable amount of variation and change that existed both before and after the mythic date of 40 14 c kyr this paper reviews and compares relevant aspects of the records from europe and africa and then focuses on the iberian peninsula to highlight the arbitrary nature of our concept of an mp up transition changes took many forms not all of them novel or abrupt with many examples of up type precursor behaviors and products in the mp many clear cases of continuity across the transition and abundant evidence that the entire phenomenon was a cultural and biological mosaic rather than starkly black and white replacement of one adaptive system by another the iberian evidence is a microcosm of the complexity of the situation which cannot be glossed over for the sake of mere simplification or to continue to prop up 19th century culture historical notions and analytical units

bone weathering in the tropical rain forest abstract bones deposited on the rain forest floor exhibit distinctly different surface modifications from those found in savannas the development of weathering cracks is considerably slower than in more open environments suggesting that the dearth of rain forest fossil assemblages is not caused by increased weathering in these environments ubiquitous surface modifications include green plant growth on the bone s exposed surfaces termite caused pitting and extensive rodent gnawing if preserved on fossil bone these modifications may serve as palaeoenvironmental indicators

geomorphological processes and their palaeoenvironmental significance at the shum laka cave bamenda western cameroon abstract the climatic environmental history of the shum laka cave western cameroon and its surroundings has been established by means of geomorphological sedimentological and botanical data tied in a well dated stratigraphical sequence since 30 000 yr bp this mountainous area 1 650 2 000 m asl has never been a desert nor a tropical forest temperatures seldom significantly dropped below freezing mountain forest with galleries along the water courses and grassland in between prevailed most of the time a certain evolution can be observed from 31 000 to 20 000 yr bp annual precipitation was initially higher than today and subsequently somewhat lower from 13 000 yr bp onwards humidity and temperatures increased again around 9 000 yr bp they probably reached higher values than today from 9 000 yr bp human activity became very apparent this may have influenced the evolution of the natural landscape and obliterated climatological effects this evolution has been interrupted three times by dryer climatic conditions which each time lasted for only 1 or 2 millennia respectively at 33 000 at 11 000 and at 3 000 yr bp another important less humid episode occurred between 6 070 and 3 180 yr bp finally there is some evidence for a drier period between 8 480 and 7 150 yr bp the climatic evolution established for the shum laka cave confirms and refines former data from the area and is in good agreement with data from barombi mbo and chad

the ongeluk basaltic andesite formation in griqualand west south africa submarine alteration in a 2222 ma proterozoic sea abstract the ongeluk lavas form part of the palaeoproterozoic transvaal griqualand west supracrustal sequence of the archaean kaapvaal craton of south africa they form a thick shallow marine volcanic sequence of pillow lava massive flows and hyaloclastite which together with their comagmatic subaerial hekpoort correlate once covered most of the craton in this study the magmatic composition and alteration features of ongeluk samples were distinguished using geochemistry and radiogenic isotopes the ongeluk hekpoort magma was a basaltic andesite derived from anomalous kaapvaal craton lithosphere with a long history of high u pb high rb sr and chur like sm nd ratios little evidence for magmatic fractionation was found although contamination of the lower lavas with cr rich material is evident in both hekpoort and ongeluk sequences the alteration of ongeluk lavas is characterised using diagrams which compare pillow core rim pairs hyaloclastite and massive lava samples with the estimated original magma composition alteration is ascribed to a shallow 87 sr 86 sr ratios decreased from magmatic 0 7071 towards seawater 0 7025 during submarine alteration the rb sr system also reveals a much later 1200 ma phase of ca and rb mobility in a few samples in contrast the submarine alteration affected pb isotope ratios so little that a 2222 13 ma isochron age is regarded as a refinement of earlier dates for the ongeluk hekpoort extrusion the ongeluk hyaloclastites acted as a sink for k and rb in the overlying sea while the mn and ca entering the sea could have contributed to the overlying kalahari manganese deposits

a new palaeolithic discovery tar hafted stone tools in a european mid pleistocene bone bearing bed two stone flakes partly covered in birch bark tar and a third without tar on it were discovered in fluvial gravel and clay in central italy in association with the bones of a young adult female elephas palaeoloxondon antiquus and several micromammals the probable chronology of the stone flakes is compatible with the late middle pleistocene suggested by the site s small mammals and geological context the fauna indicates a cool stadial episode before isotope stage 6 that age means the flakes are the oldest ever found hafted with tar and indicate a greater capacity for late middle pleistocene hominins to utilize raw materials available during cold phases

geochronological evidence for tectonically driven brine migration during the early proterozoic kheis orogeny of southern africa the 2 1 1 9 ga kheis orogeny on tne western margin of the kaapvaal craton of southern africa induced regional heating tilting and extensive fluid flow which isotopically reset and altered rocks and minerals of older proterozoic formations and parts of the archean cratonic basement this tectonic event is recognised in the ar rb sr pb pb and u pb zircon geochronological and palaeomagnetic studies on the transvaal and underlying basement rocks

accelerator 14c dates for early upper paleolithic basal aurignacian at el castillo cave spain abstract three fragments of charcoal taken from different parts of the lowermost bed containing aurignacian artifacts at el castillo cave yielded ams dates of 37 7 1 8 ka bp 38 5 1 8 ka bp and 40 0 2 1 ka bp average 38 7 1 9 ka bp these dates are almost identical to new ams dates from l arbreda cave in catalunya on the same cultural horizon average 38 5 1 0 ka bp and are significantly older than the earliest dates for aurignacian industries in the aquitaine and in other parts of central and western europe

new dates and palaeoenvironmental evidence for the middle to upper palaeolithic occupation of higueral de valleja cave southern spain a research programme has been set up at higueral de valleja cave in southern spain to investigate the late survival and eventual extinction of the southern iberian neanderthals and the arrival of modern humans of key interest in the first phase of research was to understand the depositional environment in the entrance chamber of the cave and to establish whether palaeoenvironmental and dating samples could be retrieved from the middle and upper palaeolithic sequences the outcome is a series of osl tl and radiocarbon dates showing that the cave was occupied by neanderthal populations in marine isotope stage mis 3 if not earlier and by modern human solutrean populations during the last glacial maximum cave sediments provisionally indicate that the lower middle palaeolithic sequence x viii formed in warm and humid environments and the upper sequence viii v formed when the climate was cooler and drier the presence of long grass phytoliths and of the small mammals microtus duodecimcostatus microtus brecciensis and apodemus sylvaticus in the upper sequence indicates that a range of habitat types persisted near the cave including grassland scrubby vegetation patchy tree cover and ponds this raises the possibility that environmental factors were key factors in the late survival of neanderthal populations at the cave

sea level changes an integrated approach sea level changes an integrated approach in october 1985 sepm sponsored a four day conference entitled sea level changes an integrated approach the purpose of the conference was to provide a forum for an interdisciplinary exchange of ideas on sea level changes and to provide an opportunity for integrating various types of evidence in approaching unresolved issues the conference was successful in bringing together scientists from industry academia and government representing all of the major geosciences disciplines presentations of many new papers plus significant releases of data that were previously held proprietary provided fertile ground for discussion this much cited volume represents the best of the material presented at the conference includes the early vail chart

sedimentology and geomorphology of overbank flows on meandering river floodplains abstract along floodplains there occurs an ordered sequence of geomorphic events during floods the following sequence occurs for individual flood events 1 the rise of floodwater and of groundwater 2 the inundation of the floodplain 3a adjustments of the overbank flow pattern to the floodplain environment 3b the flood peak 4 the initial fall of floodwaters and changes in the overbank flow pattern 5 a gradual cessation of the overbank flow 6a infiltration evaporation and a wave like motion of stagnant water and 6b postflood transformation under subaerial conditions field observations support this model for meandering rivers in the polish lowland

ash bones and guano a study of the minerals and phytoliths in the sediments of grotte xvi dordogne france abstract very few prehistoric cave deposits in western europe contain visible hearth remains even though there is abundant evidence of fire use by cave inhabitants grotte xvi dordogne france is exceptional in this respect in that it contains a most conspicuous layer couche c characterized by a series of brightly coloured bedded sediments the formation of couche c has previously been ascribed to the ash and charcoal produced by the cave s mousterian occupants burning mainly lichens the mousterian sedimentary layers below couche c and the upper palaeolithic sediments unconformably overlying couche c are quite different in texture and colour and show no visible evidence of ash deposits analyses of the minerals microstructures and phytoliths in couche c are consistent with the notion that these sediments were derived mainly from ash produced by burning wood and to a lesser extent grass the original calcite component of the ash has been diagenetically altered to carbonated apatite around the cave periphery and to even more insoluble phosphate minerals in the centre one such mineral newberyite most likely formed by the reaction between guano degradation products and the ash under these circumstances bone preservation is also affected the overlying upper palaeolithic sediments contain calcite one of these layers abb contains much more calcite than all the other layers as well as abundant phytoliths derived from wood and grass this layer also contained many artifacts and bones it is thus concluded that ash is a major component of layer abb even though it is not visible to the maked eye in the form of hearths

assessing the macrofracture method for identifying stone age hunting weaponry abstract macrofracture analysis is an experimentally derived method used as an initial step in investigating the hunting function of stone artefacts diagnostic impact fractures which can only develop as a result of longitudinal impact underpin this method macrofracture analysis recently gained favour in middle stone age studies supporting hypotheses for effective hunting during the late pleistocene in southern africa however the factors affecting diagnostic impact fracture formation and the interpretation of these fracture frequencies are not yet fully understood this paper outlines a set of experiments designed to test macrofracture formation under human and cattle trampling and knapping conditions the results show that a macrofractures occur frequently when stone artefacts are trampled by cattle and humans and in knapping debris b diagnostic impact fractures occur on some of the trampled flakes and knapping debris 3 but significantly less often than in previous hunting experiments c when they do occur they are likely produced by longitudinal forces similar to those experienced during hunting d considering artefact morphology is important during macrofracture analysis and e macrofracture analysis is not a standalone method but is most useful as part of a multi analytical approach to functional analysis these experiments help to establish a significant baseline diagnostic impact fracture frequency for the interpretation of archaeological macrofracture frequencies

experiments on bed configurations in fine sands under bidirectional purely oscillatory flow and the origin of hummocky cross stratification abstract we made experiments on bed configurations in bidirectional purely oscillatory flows at a wide range of oscillation periods t and maximum orbital velocities um in two closed flow ducts 0 1 m and 0 4 m wide the motivation was that understanding of bed configurations in oscillatory flows with long periods and high velocities during storm induced deposition in the shallow ocean is needed for interpreting the stratification in such deposits the ripples produced were classified geometrically as two dimensional 2d or three dimensional 3d in plan view geometry and dynamically as oscillatory current ripples dependent upon the patterns of flow and sediment transport specific to the existence of the oscillation itself and reversing current ripples dependent on he existence of the current in one direction or the other during the oscillation runs in the small duct with effectively 0 19 mm and 0 30 mm sand showed the familiar small 2d oscillatory current ripples at short t and low um passing into much larger ripples with spacing up to 2 m at periods of 6 20 s and velocities up to 1 m s with no apparent limit on size with increasing t and um even in such a narrow duct there was some evidence of 3d geometry of the large ripples runs in the large duct with effectively 0 11 mm sand at a single period of about 9 5 s showed a progression from small 2d oscillatory current ripples through small 3d reversing current ripples to large round crested 3d oscillatory current ripples with prominent superimposed 3d to 2d reversing current ripples the large 3d ripples which increased in spacing to 1 3 m at the h ghest attainable um of 1 m s shifted in position and changed in size with time seemingly at random causing substantial local and temporary erosion and deposition at a given point on the bed there was no net aggradation during the runs but a deposit was synthesized by taking a time series of sidewall bed profiles during a run in which large 3d ripples developed from an initially plane bed and changed irregularly in size and position as they grew toward equilibrium and then plotting the profiles one above the previous with a constant upward increment the resulting stratification is strikingly similar to much hummocky cross stratification in ancient sandstones this suggests that some hummocky cross stratification is generated during sediment fallout from strong purely oscillatory flows at moderate to long oscillation periods as large 3d oscillatory current bed forms develop from a planar bed during strong but waning flow

u series isochron dating a generalized method employing total sample dissolution the age of a sedimentary deposit can be determined by measuring 238u 234u 232th and 230th in two or more samples of the deposit with the requirement that these samples have different u th ratios but an identical 230th232th ratio when deposited this paper presents the theoretical and experimental aspects of the dating method the latter involves techniques for securing samples of varied u th ratios from the same deposit plotting isochrons of the radiochemical data obtained on totally dissolved samples for age analysis and estimating the errors involved although applications to impure carbonates and lacustrine evaporite sediments are given as examples in this paper the method potentially can be generalized for dating a variety of authigenic deposits such as rock varnish peat opal sulfate minerals and marine phosphorites

facies architecture and sequentiality of nearshore and shelf sandbodies haystack mountains formation wyoming usa the haystack mountains formation campanian mesaverde group us western interior basin wyoming contains a series of shallow marine sandbodies extending tens of kilometres out from a basin margin the study succession around 200 m thick is composed of eight major sandstone tongues bolten ranch o brien spring seminoe 1 2 3 4 hatfield 1 and 2 members each partially encased within marine shale intervals the formation is sequential at several scales at the largest scale the whole succession presents an aggradational to basinward stepping stacking pattern of the sandstone tongues at a lower level each tongue member is characterized internally by two different types of lithosome the first represents shoreface progradation with hummocky cross strata passing up to swaley and trough cross stratified sandstones this lithosome is erosively truncated at its top in most cases and has a general sheet like geometry along strike whereas down dip it displays a series of sharp bounded clinothems the latter sometimes indicate a downward as well as a basinward shift through time as suggested by the occurrence of coarser and or shallower facies at a lower level in the shoreface profile the second type of lithosome is sheet or wedge like and sharply overlies the shoreface deposits the lithosome consists of laterally widespread units of planar tabular to trough cross bedded medium sandstones passing laterally in a dip direction into bioturbated sandstones the lower part of this lithosome is progradational becoming retrogradational into the overlying shales the facies within the cross bedded lithosome suggest a tidally dominated delta front to estuarine depositional setting the two types of lithosome are not related genetically the erosion surface separating the two lithosomes is a sequence boundary separating forced regressive relative sea level fall shoreface deposits from lowstand to transgressive early relative sea level rise cross bedded deposits the uppermost part of the cross stratified lithosome shows a landward stepping of component parasequences and is abruptly blanketed by open marine shales the most widespread cross bedded lithosomes are apparently best developed in the lowermost members of the haystack mountains formation i e in the aggradational part of the large scale progradational succession in the uppermost highly progradational sandstone tongues the shoaling upward shoreface lithosome dominates whereas the cross bedded lithosome occurs in narrow lensoid belts or is absent the middle portion of the succession shows intermediate characteristics the vertical variation in geometry thickness and progradational extent of successive cross bedded lithosomes results from greater confinement of the incised nearshore systems both in space landward direction and in time from the aggradation to the progradation architecture the latter is a consequence of a decreasing rate of accommodation creation through time

cave sediments upper pleistocene stratigraphy and mousterian facies in cantabrian spain abstract archaeological sediments are analysed from karst cave columns in cantabrian spain cueva morin el pendo the castillo cave complex including la flecha las chimeneas la pasiega las monedas hornos de la pena and cobalejos external sediment influx including loess is calibrated by an index of cave and slope run off energy while other features slope and roof rubble chemical precipitates cryoturbations fine soil derivatives and cultural components are discussed the key sequences morin el pendo castillo are each interpreted in local terms and then combined into a regional climatostratigraphy that includes 40 environmental phases within deep sea isotope stages 2 5 trends in run off energy reflecting slope stability temperature and summer moisture are rarely in phase indicating complex environmental change mid pleistocene and older deposits exist but have largely been destroyed explaining the apparent absence of acheulian settlement mousterian occupation is verified by isotope stage 5b and two or three mousterian facies that span 25 50 000 years are coeval in several caves regardless of the direction of climatic oscillations this suggests the flexible lithic technology of a single population maintaining an adaptive steady state despite repeated environmental changes by contrast the distinct upper palaeolithic industries each span only a few millennia but in part overlap temporally within the region between 35 000 and 9500 bp

morphological and sedimentary evolution of an alluvial floodplain in an urban area geoarchaeological approaches and applications tours france urban zones on alluvial plains offer considerable geoarchaeological potential for understanding river dynamics over large time spans and their relationship with land use because of the extensive subsoil data that is available in the alluvial plain of tours lying between the loire and the cher multidisciplinary studies of the relationships between societies and environment have been conducted as part of an archaeological research programme launched in the 1960s a sedimentary database containing data for 1309 surveys has been compiled and assembled in a geographic information system to produce geostatistical models of valley bottom geomorphology the stratigraphy and chronology of alluvial filling have also been studied with information and c14 and osl dating obtained during archaeological operations taken together the results offer a new interpretation of the morphological evolution of the alluvial plain of tours from the weichselian to the present day by providing new information that either validates or invalidates previous hypotheses bedrock incision prior to the end of the weichselian upper pleniglacial coarse sedimentation during the lateglacial relative morphological stability up to the late holocene the morphological context of the first human settlements which are not concentrated on the low alluvial reliefs and the role of urbanization conditions on the present morphology of the valley floor are also presented this applied study shows the relevance of combining different methodological approaches

archaeological site formation in rain forests insights from the ituri rock shelters congo abstract this contribution complements the existing literature on rock shelter geoarchaeology and site formation processes by presenting data from 10 granite rock shelters in a tropical rain forest environment geological taphonomic pedological and archaeological data are used to assess the geomorphological evolution of rock shelters in the ituri rain forest northeast democratic republic of congo mechanisms of sediment production and deposition soil formation and related site formation processes were investigated the implications for the preservation of archaeological materials and stratigraphic resolution are discussed rock shelters in the tropical environment of the congo basin are formed by mechanical and chemical denudation of large granite boulders the current geomorphological cycle of rock shelter formation and collapse dates to the late pleistocene and may have been accelerated by anthropogenic forces the sedimentary record includes in situ breakdown products from the rock shelter walls while off site sources are represented by a minor influx of colluvium soil forming forces have acted on these matrices humans introduced charcoal phytoliths endocarps shell animal and human bone as well as inorganic materials such as stone ceramics and metal lags of archaeological materials are common under driplines where fine sediments have been washed away and include artefacts of different ages there is no evidence of extensive bioturbation but limited disturbance by roots burrowing animals and termites has been documented although there is some horizontal and vertical movement of prehistoric artefacts the post depositional translocation of materials is not significant we conclude that the stratigraphic integrity of these granite rock shelter sites with multiple archaeological horizons and the potential for the long term preservation of organic materials in a tropical environment are better than previously thought

forced regressions in a sequence stratigraphic framework concepts examples and exploration significance sequence stratigraphic concepts suggest that stratal geometries develop and are largely controlled by changes in relative sea level on the shelf lowstand deposits which form during falls and subsequent stillstands of relative sea level can be recognized by the presence of an unconformity at the base the isolated and basinward position relative to the previous shoreline and the abrupt seaward translation of shallow water and shoreline facies into the basin across an unconformity surface this seaward translation of facies and shoreline regression in response to relative sea level lowering is termed a forced regression a forced regression is independent of variations of sediment flux and is in contrast with normal regressions that occur in response to excess sediment flux relative to space available on the shelf i e accommodation forced regressions commonly are associated with a zone of sedimentary bypass subaerial exposure and possible fluvial erosion between the newly formed and preceding shorelines certain shelf sands previously interpreted as offshore or mid shelf sand bodies thus can be reinterpreted as stranded lowstand shorelines associated with forced regressions this alternative interpretation has economic significance insofar as it suggests different subsurface correlations and reservoir geometries with the potential for development of new play types and enhanced recovery in o der fields examples of forced regression can be observed at a variety of scales and ages several such examples include the modern east coulee fan delta and the lower cretaceous viking formation in alberta canada the quaternary rhone delta and the quaternary hudson valley system

neandertal extinction and the millennial scale climatic variability of ois 3 population models seeking climate as a triggering factor for the extinction of neandertals and the colonisation of europe by anatomically modern humans are contradictory due to uncertainties in the dating methods in the cultural attribution of archaeological layers and to the lack of terrestrial continuous and well dated palaeoclimatic sequences this is particularly the case for the iberian peninsula where neandertal populations seem to have survived later than in other regions of europe a review of the available palaeoclimatic evidence for ois3 of iberia reveals that this mainly consists of low resolution fragmentary ill dated and often ill interpreted records correlation between palaeoenvironmental sequences from two images pollen rich deep sea cores and archaeological data from western europe the electronic archive of the radiocarbon dates is available at qsr website http www elsevier nl locate quascirev indicates that aurignacian moderns colonised france and the north of iberia at the onset of the h4 event during this cold episode a probable contraction of neandertal populations is recorded in southern iberia where no aurignacian settlements are detected such a decline in population density is correlated with the particular desert steppe like environments made up of artemisia chenopodiaceae and ephedra characterising the h4 of this area while reducing the size of neandertal populations this inhospitable environment may have favoured their persistence in this region mainly exploiting herds of herbivores adapted to graminees rich grasslands the aurignacian moderns were probably not interested in colonising these arid mediterranean biotopes and did that only after the h4 event

cyclic deposits and hummocky cross stratification of probable storm origin in upper cretaceous rocks of the cape sebastian area southwestern oregon abstract cyclic deposits containing hummocky cross stratification occur in the upper part of the cape sebastian sandstone of bourgeois 1980 a shallow marine transgressive sandstone of late cetaceous age on the southern oregon coast the cycles average 1 6 m in thickness and consist where complete of a lower hummocky cross stratified sandstone a middle planar and ripple bedded sandstone with a shale bed in its middle part and an upper bioturbated sandstone noteworthy features of the hummocky cross stratification include the presence of depositional domes in addition to scoured depressions the absence of significant bedform migration and the presence of a small proportion of dip angles greater than the angle of repose 34 in addition to the large proportion of low 15 deg dip angles the lower stratified fining upward part of the cycle up to the top of the shale bed is interpreted as having accumulated under conditions of initially great but gradually decreasing current velocity and deposition rate the currents probably had a strong oscillatory component and the depositional event is inferred to have been a storm the part of the planar and ripple bedded sandstone above the shale bed was probably deposited during relatively fair weather after the storm but before re establishment of a normal benthic fauna the bioturbated sandstone is interpreted to have been deposited during fair weather or during minor storms separated by long intervals of fair weather

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

style contrast between forced regressive and lowstand transgressive wedges in the campanian of south central wyoming hatfield member of the haystack mountains formation

shannon sandstone in wyoming a shelf ridge complex reinterpreted as lowstand shoreface deposits abstract the shannon sandstone campanian of wyoming was formerly interpreted as two stacked shelf ridge complexes sand was believed to have been transported from a time equivalent shoreline 110 150 km to the west and reworked or molded into ridges at the depositional site we show that this time equivalent shoreline section at lucerne wyoming consists of not one shoreface sandbody but two superimposed they are both storm dominated and the lower one terminates in beach facies capped by root traces there must have been a rise in relative sea level of at least 14 m to make accommodation space for the second shoreface sandbody in the salt creek area and the adjacent subsurface teapot dome there are two sandier upward facies successions in the lower succession there are abrupt vertical acies contacts between offshore bioturbated sandstones thicker hummocky cross stratified sandstones and coarser cross bedded sandstones there is also evidence that the cross bedded sandstones rest erosively on underlying facies the trace fauna in the sandstones includes macaronichnus segregatis rosselia socialis and ophiomorpha the m segregatis suggests a foreshore or upper shoreface depositional environment and r socialis indicates a lower to middle shoreface neither are characteristic of a shelf ridge complex the abrupt and probably erosive facies contacts along with the trace fauna suggest that the cross bedded sandstones in this succession represent a shoreface deposit that formed during a stage of actively falling relative sea level overlyi g muddy bioturbated sandstones indicate that shoreface deposition was terminated by a transgression the upper sandier upward succession contains facies and trace fauna similar to those of the lower succession and is also interpreted as a prograding shoreface rather than the sand moving 110 150 km from the shoreline and then being molded into shelf ridge complexes at salt creek we suggest that the shoreline moved into the salt creek area as the result of a fall in relative sea level it was transgressed and moved back westward a second fall of relative sea level moved the shoreline back to salt creek and a final transgression terminated shannon deposition

storm and tide dominated shorelines in cretaceous moosebar lower gates interval outcrop equivalents of deep basin gas trap in western canada the moosebar and gates formations crop out in the deformed foothills belt south of fort st john british columbia they permit examination of the depositional environments of sandstones and conglomerates that are gas bearing in the equivalent wilrich falher interval of the deep basin of alberta and british columbia the moosebar gates interval consists of several upward coarsening and marine to nonmarine sequences moosebar bioturbated shales pass upward into turbidites and offshore storm deposits flow directions indicate a north dipping paleoslope a second coarsening upward sequence at the top of the moosebar and base of the gates terminates in a lenticular fluvial conglomerate up to 30 m thick which is overlain by coals carbonaceous mudstones and sandstones above the carbonaceous zone a major lateral facies change is observed fluvial conglomerates in the south grade into beach conglomerates northward the upper part of the beach conglomerate consists of exposed three dimensional storm berms at least 500 m long up to 1 5 m high with wavelengths of 12 to 24 m the berms trend east west seaward of the conglomerate beach are herringbone cross bedded tidal sandstones with a marine trace fauna graded sharp based conglomerates also are present probably washed out to sea by storms farther north at the same stratigraphic level is a series of partly overlapping conglomerate bars up to 5 m thick and 40 to 50 m across the tops of these bars are covered with storm formed symmetric conglomeratic dunes details of the orientation and geometry of these conglomerate bodies along with their internal structure and pebble fabrics suggest that four major environments fluvial beach offshore conglomerate bars and offshore graded storm conglomerates should be identifiable and predictable in the subsurface

ore structure relationships at sishen mine northern cape republic of south africa based on fully constrained implicit 3d modelling abstract a fully constrained implicit 3d geological model of sishen mine reveals the original pre mining geometry of ore bodies host rocks to mineralization and major structures there are several overlapping controls at a variety of scales on the position depth and geometry of laminated and conglomeratic ore most of these controls are structural or may be reconciled with the kinematic history of this part of the maremane dome a series of near horizontal sections through the entire 3d model demonstrates the manner in which these controls overlap and interact first order or large scale controls comprise broad domes which show preservation of laminated ore around their rims outside of which conglomeratic ore occurs second order controls comprise grabens and half grabens which are often bounded by strike persistent normal faults which show fault drag on their western flanks due to inversion along with preservation of bif related supergene ore and conglomeratic ore a type example is the thick deep linear ore to the west of the sloep fault third order controls on the preservation of mineralization comprise downthrown blocks to the north of reactivated e w se ese or ne ene trending conjugate faults upthrow to the south could be attributed to the 1 15 1 0 ga nnw directed lomanian namaqua natal orogeny palaeosinkholes comprise fourth order controls which are superimposed on higher order controls palaeosinkholes which form the bulk of current mining comprise deep conical depressions with anomalous thicknesses of chert chert breccia and haematite due to their limited size the steepness of all units and the often chaotic nature of detached and slumped blocks in their centres these volumes reflect longstanding models on palaeosinkhole development and very local ore control

u series dating of impure carbonates an isochron technique using total sample dissolution abstract u series dating is a well established technique for age determination of late quaternary carbonates materials of sufficient purity for nominal dating however are not as common as materials with mechanically inseparable aluminosilicate detritus detritus contaminates the sample with extraneous th we propose that correction for contamination is best accomplished with the isochron technique using total sample dissolution tsd experiments were conducted on artificial mixtures of natural detritus and carbonate and on an impure carbonate of known age results show that significant and unpredictable transfer of radionuclides occur from the detritus to the leachate in commonly used selective leaching procedures the effects of correcting via leachate residue pairs and isochron plots were assessed isochrons using tsd gave best results followed by isochron plots of leachates only

geoarchaeological alluvial terrace system in tarazona chronostratigraphical transition of mode 2 to mode 3 during the middle upper pleistocene in the guadalquivir river valley seville spain abstract a geoarchaeological study of some lithic assemblages found in late middle pleistocene and beginning upper pleistocene alluvial terraces system has been carried out the mis 6 mis 5 transition in the fluvial terraces of the guadalquivir river has been identified in the middle terraces complex mtc at tarazona t11 1 44 38 m and t11 2 36 30 m seville spain the results were obtained from an archaeological excavation tar iii and two other complementary archaeological sites tar i and tar ii geomorphological cartography chronostratigraphic study with osl dating cantometric analysis and technotypological characterization of 5870 lithic pieces measurement techniques for erosion and transport on gravels and lithic have been accomplished the alluvial chronosequence shows a probable climatic character with autocyclic sedimentary processes correlated with the transition from mis 6 to mis 5 four alluvial episodes with associated lithic techno complexes were identified which refer to the chronostratigraphic transition from mode 2 to mode 3 during the late middle pleistocene mis 6 and the beginning of upper pleistocene mis 5 episode 1 with mode 2 mis 6 episode 2 with varied assemblages that could be associated to mode 2 or mode 3 129 121 ka mis 5e and mis 5d pre 110 ka episode 3 with mode 3 between 110 and 104 ka mis 5c and episode 4 with mode 3 post mis 5c the archaeological sites have lithic pieces which were knapped in situ workshop habitual or temporary sites or were slightly displaced the raw material selection of high quality quartzites from alluvial deposits is very notable during mode 2 acheulian tar i2 mode 2 or mode 3 assemblages tar iii5 and mode 3 tar iii1 2 3 during mode 3 middle paleolithic tar ii1 the selection of flint raw material was from areas near or in the guadalquivir terraces

the statistical modelling of the grain size distributions of cave sediments using log skew laplace distributions creswell crags near sheffield england this paper describes the statistical modelling of cave sediment size data using log skew laplace distributions the sediment samples were obtained from excavations in three archaeologically important palaeolithic deposits in the creswell crags caves which occur in the infrequently studied lower magnesian limestone permian bedrocks east of sheffield england theoretical and practical justifications for employing this and other types of statistical distribution to model grain size data are briefly reviewed three independent and one summary descriptor based upon parameter measures derived by fitting log skew laplace models to cave sediment grain size data are then used to explore the relationships between sediment location specifically distance of the sample from the cave entrance s in three caves which differ in their geomorphic complexity in the most complex cave robin hood s cave broadly defined groupings or sediment trajectories were detectable in 3d displays of the parameter values for samples from individual columns of the sampled cave sediments the relatively simple sac cave pin hole cave appears to show relatively simple zonal trends in the descriptors with variation in the outermost part of the chamber being primarily responsible for the trends observed zonal trends were also suggested but less clearly by some of the independent descriptive parameters in the more complex church hole cave but in this case it was the properties of the innermost samples that were responsible for much of the apparent variation detected on the basis of this statistical modelling and the associated exploratory data analysis it is hypothesized that textural variations in these three caves can be provisionally disaggregated into at least two complex elements the first manifests itself in zonal variations which appear to relate directly or indirectly to the effects of increasing distance from these cave mouths essentially akin to the ideas of schmid 1969 science in archaeology pp 151 166 london thames and hudson the second discloses itself in more location specific variations which themselves reflect the local sedimentary circumstances of that particular site within robin hood s cave similar to the ideas of butzer 1971 environment and archaeology an ecological approach to prehistory chicago aldine

a collision related pressure temperature time path for prieska copper mine namaqua natal tectonic province south africa abstract prieska copper mine lies in highly metamorphosed gneisses of the 1100 ma namaqua natal tectonic province of south africa close to its boundary with the kaapvaal craton the complex stratigraphy of the mining district is thought to have formed in a 1300 ma arc environment while the ore is regarded as a volcanogenic massive sulphide deposit petrographic study of key peraluminous and metabasic rock types led to the recognition of four principal metamorphic events m 1 4 which together with three deformation phases constitute an orogenic cycle staurolite garnet kyanite m 1 parageneses reflect medium pressure metamorphism but are largely obscured by the dominant m 2 muscovite free cordierite garnetsillimanite assemblages the latter reflect the metamorphic peak at about 730 c and 4 1 kbar with partial melting suppressed by dry conditions m 2 peak temperatures at different localities within the 30 km long mining district vary between 550 and 800 c suggesting a localized heat source m 3 sillimanite phlogopite grain boundary reactions represent a brief hydration event in p t conditions close to those of m 2 m 4 parageneses which feature retrograde kyanite staurolite garnet muscovite and chlorite are developed only in f 3 shear zones and represent a near isobaric return to a geotherm close to that which prevailed during m1 p t data for the metamorphic cycle is integrated with comprehensive geochronology to develop a model ptt path for the prieska mine region the model envisages an orogenic cycle at the end of a 1300 900 ma wilson cycle characterised by collision crustal thickening followed by a long period of uplift and erosion the peak metamorphic conditions are ascribed to two short lived essentially contact metamorphic events due to the intrusion of the plat sjambok anorthosite suite the 400 ma wilson cycle 300 ma orogeny and 0 05 mm yr uplift rate envisaged for prieska mine are long and slow compared with phanerozoic examples however similar parameters seem to characterize more than one proterozoic event

h4 abrupt event and late neanderthal presence in iberia heinrich event 4 h4 is well documented in the north atlantic ocean and the adjacent continents as a cooling event 39 000 yr before present bp to quantify the impact of this event with respect to climate and vegetation over the iberian peninsula we perform numerical experiments using a high resolution general circulation model forced by sea surface temperatures before and during h4 our model simulates an expansion of aridity over the peninsula during h4 a desertification of the south and a replacement of arboreal by herbaceous plants in the north all of which are in agreement with contemporaneous pollen sequences from marine cores located off the iberian peninsula our simulations demonstrate that the h4 marine event imprinted drastic changes over southern iberia which would not have favoured its occupation by anatomically modern humans therefore providing a plausible explanation for the delayed extinction of neanderthals in this region inferred from the archaeological record

formation processes at a high resolution middle paleolithic site cueva anton murcia spain cueva anton is a middle paleolithic rockshelter located in the valley of the river mula murcia spain the archeological investigation of the site which began with salvage work in 1991 resumed in 2006 and is still ongoing uncovered a succession spanning most of mis 3 and mis 4 ca 75 36 ka and featuring a well preserved human occupation record this paper presents the first information about site stratigraphy and site formation processes geoarcheological data collected in the field and through micromorphological observation show that the archeological succession at cueva anton is mainly composed of alluvial sediments with thin intercalations of gravitational and slope material the sedimentary characteristics of the alluvial succession are well preserved as the result of a rapid accumulation rate and the protective effect of the rockshelter several sedimentary facies produced by the shifting of distinct fluvial sub environments channel bar and floodplain are recognized with the exception of a few units ii u a thin buried alluvial soil and the archeologically richest units at the base of the succession post depositional modification is rare the site was occupied within a framework of infrequent short term visits resulting in a relatively low overall density of finds and the formation of well defined archeological lenses that correspond to synchronous paleosurfaces preserving the spatial distribution of finds and features this pattern explains the limited anthropogenic evidence observed in thin sections even those from units where archeological excavation uncovered significant remains of human occupation

surface sediments and sequence models in the ebb tidal delta of texel inlet wadden sea the netherlands abstract grain size and primary sedimentary structures in the ebb tidal delta of texel inlet are described with the emphasis on the relations with tidal and wave processes grain size distribution curves represent two major types wave dominated very well sorted sand with dominantly saltation population and tide dominated less well sorted with relatively large suspension and traction populations areal distribution of mean grain size sorting and different distribution curves is closely related to sediment transport patterns the deep inlet channel and the offshore area serve as source areas for the ebb tidal delta and have coarse relatively poorly sorted sediments deposition of very well sorted fine sand occurs on the shallow ebb delta shoal the size and sorting of the sands are the result of selective transport and wave processes sedimentary structures formed by waves and tidal currents are distinctly distributed over the shallow ebb delta shoal the channels and the adjacent inner shelf the areal distribution of mud drapes in the ebb tidal delta is a combined effect of the local tidal current pattern and the related locally high concentrations of fine grained suspended sediment alternation of tidal current dominance during and immediately after storms with wave dominance during fair weather conditions results in the formation of storm deposits at specific locations in the ebb tidal delta i e seaward of the main ebb channel on the basis of this study sequential models are proposed for the migrational inlet channel the progradational ebb delta lobe and the landward migrating ebb delta shoal the transgressive sequence formed after abandonment of the ebb delta lobe

absolute dating of hominids and palaeolithic artifacts of the cave of la chaise de vouthon charente france abstract two adjacent chambers of the cave of la chaise grotte de bourgeois delaunay b d and grotte suard have been studied both were partly filled with detrital sediments containing lower and middle palaeolithic artifacts and skeletal remains of pre neanderthalian hominids layers of stalagmitic calcite occur interstratified in the sediments of both chambers dates obtained by 230th 234u ratios have provided a time scale for hominid and cultural evolution as represented in this cave in b d the lower travertine rests on a breccia containing cranial remains of juvenile neanderthals the base of the travertine dates to 151 15 ky ky 1000 years bp the top of the travertine yields a date of 112 5 ky the travertine contains pollen of an interglacial flora overlying detrital sediments 1 2 m in thickness contain artifacts transitional from acheulian to mousterian industries they are capped by a travertine layer 7 whose base is dated at 100 6 ky and which is capped by stalagmites ranging in age down to 58 7 ky overlying the travertine is sediment containing first mousterian and then aurignacian artifacts near the base of the sediments filling grotte suard is a stalagmite layer dated to 249 30 ky it contains interglacial pollen and presumably dates to the beginning of the isotope stage 7 interglacial neanderthaloid hominid teeth and cranial fragments are found scattered through the overlying sediments up to a capping stalagmitic layer whose base is dated at 101 7 ky the best described hominids from suard are from a section that was probably overlying the capping stalagmite the capping stalagmite is temporally correlated with layer 7 of b d

a test of uranium series dating of fossil tooth enamel results from tournal cave france abstract a series of well preserved mammal bones and horse teeth was analyzed from archaeological levels of tournal cave magdalenian aurignacian and mousterain to test the hypothesis that well crystallized enamel behaves more as a closed system than does whole bone the isotopic composition of bones and tooth enamels from this deposit meet criteria for confidence and gave no reasons to suspect contamination or open system behavior two samples for which231pa could be analyzed showed internal concordance with the respective230th ages in spite of the favourable isotopic criteria however comparison of the u series ages of the bones and the tooth enamel with stratigraphic position and14c control indicated the dates were not meaningful in general both bones and tooth enamels gave ages too young although some were clearly too old neither group showed any systematic increase of age with stratigraphic depth tooth enamel therefore shows no advantage over bone for u series dating for this site in tournal cave both bones and enamel are apparently open to u which is probably cycling as a consequences of post depositional groundwater movement

uranium series dating uranium decays through a number of radioactive daughter isotopes some of which have half lives comparable to the time scale of prehistoric archaeology the growth of these isotopes in naturally occurring materials at archaeological sites can be used to determine the age of sites the growth of 230th from its parent 234u can be used over a time range from a few hundred to half a million years calcite precipitated from running or dripping water in springs and caves as well as marls and soil deposited calcretes may be spatio temporally associated with archaeological materials they can be dated by 230th 234u and 234u 238u measurements with a precision of 5 10 of the age by alpha counting or 1 by mass spectrometry bones teeth mollusk and egg shells are also datable but present problems due to migration of parent u in and out of the samples during their burial history

spit platform temperate carbonates the origin of landward downlapping beds along a basin margin lower pliocene carboneras basin se spain lower pliocene temperate carbonates exhibit landward downlapping beds at the southern margin of the carboneras basin in south eastern spain this rarely documented stratal geometry resulted from the accumulation of bedded bioclastic carbonate sand and gravel by longshore currents along a spit platform located a few hundred metres from the palaeoshoreline the top of the spit platform was covered by shoals that extended over a gently dipping ramp inclined to the north on the landward slope of the spit sediments washed over from the shoal area were deposited in parallel laminated beds with a southward dip of 8 11 these beds aggraded and retrograded after an increase in accommodation space probably related to an early pliocene eustatic sea level rise as a result the beds downlap onto the underlying unconformity surface in a shoreward direction eventually the depression between the shoreline and the spit platform was filled and a gentle ramp became established these pliocene exposures in the carboneras basin and a similar upper miocene example in southern spain suggest that landward downlapping stratal geometries can be expected in nearshore temperate carbonates along basin margins and demonstrate a similarity in sedimentary dynamics to siliciclastic sands and gravels

tephra in caves distal deposits of the minoan santorini eruption and the campanian super eruption abstract tephra deposits in caves are not only significant as stratigraphic markers the comparatively sheltered position of cave environments protected from rainfall may preserve original distal tephra deposition features unlikely to have survived in the open landscape most reported findings of tephra in caves are from the campanian super eruption which originated in the area of naples italy these findings facilitate evaluation in different caves of facies variability and modes of tephra deposition derived from the same eruption the campanian volcanic event about 40 000 years ago was the largest eruption in europe and the mediterranean region during the late pleistocene another major volcanic event during the quaternary was the more recent santorini eruption in the eastern mediterranean aegean sea during the late minoan cultural period approximately 3600 years ago this was the largest holocene eruption in the region but tephra deposits in caves from this event appear to be very rare we present here the first ever finding of a visible tephra layer from the minoan santorini eruption in a cave the pure tephra situated in the pelekita cave in eastern crete near kato zakros has a thickness of up to 9 cm geochemistry analyses of major elements by electron probe micro analysis epma and trace elements by laser ablation inductively coupled plasma mass spectrometry la icp ms prove the tephra to be derived from the minoan santorini eruption radiocarbon dating also fits the time frame of this eruption our findings indicate that the tephra layer in the pelekita cave is an air fall deposit the lower boundary of the tephra layer is sharp and wavy draping over the underlying irregular cave surface particle size distribution of the tephra is bimodal and typical for suspended aeolian transport the consistently smaller size of heavier feldspar particles adjacent to larger but lighter volcanic glass particles in thin sections of undisturbed samples corroborate emplacement of the tephra inside the pelekita cave from high altitude fallout

site formation and chronology of the new paleolithic site sima de las palomas de teba southern spain abstract the newly identified paleolithic site sima de las palomas de teba hosts an almost seven m thick sediment profile investigated here to elucidate the rock shelter s chronostratigraphy and formation processes at its base the sediment sequence contains rich archeological deposits recording intensive occupation by neanderthals luminescence provides a terminus ante quem of 39 4 2 6 ka or 44 9 4 1 ka osl and 51 4 8 4 ka tl this occupation ended with a rockfall event followed by accumulation of archeologically sterile sediments these were covered by sediments containing few middle paleolithic artifacts which either indicate ephemeral occupation by neanderthals or reworking as suggested by micromorphological features above this unit scattered lithic artifacts of undiagnostic character may represent undefined paleolithic occupations sediment burial ages between about 23 0 1 5 ka osl and 40 5 3 4 ka pirir provide an upper paleolithic chronology for sediments deposited above the rockfall finally a dung bearing holocene layer in the uppermost part of the sequence contains a fragment of a human mandible dated to 4032 39 14 c yr bp overall the sequence represents an important new site for studying the end of neanderthal occupation in southern spain

seminoe 3 a tidally influenced lowstand wedge and its relationships with subjacent highstand and overlying transgressive deposits haystack mountains formation cretaceous western interior wyoming usa abstract the campanian haystack mountains formation wyoming usa consists of a series of deltaic estuarine and shoreface sandstone tongues stacked in basinward stepping units separated by shale intervals regional analysis indicates that the tongues have a distinctive two tiered architecture a a lower sandbody with bioturbated and hummocky strata of wave dominated shoreface origin and b an erosively based upper unit with bioturbated to tabular cross bedded sandstones this study focuses on a single tongue seminoe 3 which crops out in a 40 km long continuous dip oriented exposure in its landward reaches westwards the tongue consists of a thin unit of offshore transitional to lower shoreface deposits in the central part of the exposure it becomes thicker and consists of a cross bedded wedge which truncates the shoreface deposits and pinches out by downlap eastwards onto a thick westward migrating shoreface lithosome spit probably developed on the margin of a wave dominated delta detailed correlation and mapping of bounding surfaces indicate that the shoreface and spit lithosomes were deposited in a forced regressive mode during falling relative sea level the overlying cross bedded lithosome is a lowstand wedge which prograded over an incised topography created during the early stage of sea level lowstand a large embayment is suggested to have developed during the highstand forced regressive phase with shoreline and spit deposits prograding from opposing sides significant erosion and truncation occurred during the lowstand phase as well as a basinward shift of facies onto the shelf and the pre existing spit deposits in the early stage of transgression the embayment was drowned and a tide dominated estuarine environment was established the resulting cross bedded wedge displays an aggrading to prograding stacking pattern of parasequences with the uppermost portion exhibiting a retrogradational pattern as a consequence of the reworking operated by the transgression

missing records and depositional breaks in french late pleistocene cave sediments abstract cave entrance and rock shelter infillings are positioned within the pleistocene chronology for three areas of france northern alps franche comte and perigord despite minor local variations it is possible to identify regional types with a consistent depositional record over long intervals of time the interregional variability relates to the frequency and position of the gaps within the infillings sites in the northern alps have not yielded any artifacts older than the upper paleolithic magdalenian and dated sedimentary sequences do not go back beyond the older dryas more complete sequences in franche comte contain mousterian industries two major gaps occur here one lasting about 50 000 yr during the lower glacial and lower pleniglacial periods and the other lasting some 10 000 yr during the upper pleniglacial the sequences are more complete in the perigord where all major climatic phases have been identified with no significant sedimentary gaps differences in sedimentary records can be explained by variations in regional conditions during the last interglacial glacial cycle and especially by the distance from the maximum advance of ice daring glaciation

the significance of stratigraphic discontinuities in iberian middle to upper palaeolithic transitional sites the extinction of the neanderthals remains an open question and the current chronological archaeological and paleoclimatic evidence reflects complex regionally diverse scenarios for the iberian peninsula the existence of early upper palaeolithic assemblages in the north of spain raises questions about the influence of incoming upper palaeolithic groups on the native neanderthals however this evidence remains unexplained from a historical perspective at the same time recent paleoclimatic data suggest that the environmental effects of heinrich event 4 entailed a gap in human presence at the middle to upper palaeolithic boundary casting doubts on the archaeological evidence from the north of spain in order to evaluate the evidence of continuity vs discontinuity of human occupation in the iberian peninsula at the passage from the middle to the upper palaeolithic a concise overview was conducted of lithostratigraphic data available in the archaeological literature on iberian sites known to represent the middle to upper palaeolithic transition the bulk of published sites show stratigraphic discontinuity between the latest middle and earliest upper palaeolithic evidence and in many cases the sedimentary record reflects cold climatic conditions this data support the existence of a gap in human presence in disagreement with theories involving contact and acculturation and suggesting that climate might have played a significant role in the population dynamics of the iberian peninsula at the middle to upper palaeolithic boundary

climatic stages recorded in sediments of the gunang cave south korea abstract this paper presents and analyses lithological stratigraphic and geochronological data on the gunang cave which is an important archaeological site in south korea it discusses problems of the age and origin of its sedimentary sequence which consists of clastics and hardpan speleothems the sediments compose a 4 m thick lens near the cave entrance the lens formed during the middle late pleistocene and holocene according to 14 c and u th dating the changes of cave environments are reconstructed based on sedimentological palynological mineralogical magnetic and geochemical data the clastic sediment unit consists of roof fallen limestone debris cemented by fine grained matrix the matrix is dominated by silt 80 which aeolian component is 60 65 the amount of the wind blown component is persistent throughout the clastic layers suggesting a relatively stable depositional process in dry environment in contrast three lime cemented hardpans formed in a wet environment of groundwater seepage the revised age model suggests that the hardpans formed in early mis1 mis 5 5 and mis 7 and therefore correspond to the wetness maximums of these warm stages

a palaeoecological study in the western mediterranean area the upper pleistocene pollen record from cova beneito alicante spain abstract results are presented of palynological analyses of pleistocene deposits at cova beneito an archaeological site on the southern slopes of the sierra de benicadell alicante province se spain 650 m a s l with a wsw orientation the chronology is supported by radiocarbon dating archaeological evolution previous local sequences and recourse to several wider correlations for the first time in the region a warming event is defined in the mid last glacial stage during this event vegetation took on a mediterranean character with sclerophyllous elements such as quercus olea phillyrea rhamnus helianthemum etc the rest of the sequence shows a predominance of pinus within the ap phases of steppe like character and an aridity crisis immediately after the climate improvement due to local conditions forest cover was never very great

formation processes and stratigraphic integrity of the middle to upper palaeolithic sequence at cova gran de santa linya southeastern prepyrenees of lleida iberian peninsula sediments from cova gran de santa linya southeastern prepyrenees of lleida iberia are investigated by geoarchaeological means micromorphological textural quartz grain morphoscopy and geochemical analyses are coupled with stratigraphic and sedimentary macroscopic data to provide new insights into the formation processes and the integrity of the occupation layers and embedded sterile deposit documented at the middle to upper palaeolithic boundary direct indicators of the anthropogenic and natural dynamics involved in the deposition and alteration of the sediments investigated are provided results reveal the presence of in situ combustion structures as a major sedimentary indicator of human activity and occupation surfaces at the site the overall good preservation of the combustion residues indicates that occupation layers have been preserved in their original context of deposition traits of surface exposure in parallel to progressive lessening of evidence related to human activity at the top of the middle palaeolithic sequence suggest discontinuity in the occupation of the site and a possible abandonment of the rock shelter at the end of this period formation processes of the sterile deposit documented between the mousterian and the early upper palaeolithic levels involved the accumulation of debris from local sediments and soils as well as from the structure of the rock shelter soil forming dynamics related to palaeoenvironmental moisture fluctuations have also been recorded throughout the sequence investigated and indicate periods of surface stability during the formation of the sterile deposit environmental dynamics active during the formation of the sterile partially disturbed the top of the mousterian layer however our data indicate that such dynamics did not substantially affect the overall integrity of the archaeological record our results highlight the crucial contribution of geoarchaeology and microstratigraphy to the characterisation and assessment of the anthropogenic and natural dynamics involved in the accumulation and taphonomy of middle to upper palaeolithic sequences

macrotraces of middle pleistocene bifaces from two mediterranean sites structural and functional analysis abstract this article presents an analysis of the functional potential of two sets of acheulean bifaces from south eastern france bifaces from terra amata mis 11 10 nice and bifaces from au 27 of lazaret cave mis 6 nice are analyzed in order to determine how they were used the technological and morphological characteristics of bifaces are linked to create groups with equivalent functional potential this analysis is completed by a low power use wear analysis of the artefacts in order to determine how these tools were used through comparisons with experimental data functional data were obtained on two bifaces with distal bevels from terra amata and on two bifaces with distal bevels and two bifaces with active edge points from au 27 use wear on the distal bevels was interpreted as the result of handheld percussion activities for the edge points of the pieces from au 27 use wear was linked to a linear longitudinal tool motion technological morphological and functional data from bifaces from both sites are compared here to assess the evolution of the functional status of this artefact during the middle pleistocene the persistence of bifaces with distal bevels for percussive activities and the presence of bifaces with long cutting edges in au 27 are highlighted

uranium series isochron dating at el castillo cave cantabria spain the acheulean mousterian question abstract a massive flowstone layer level 23 near the base of the stratigraphic sequence in el castillo cave cantabria spain is dated by the uranium series isochron method to 89 11 10 ka bp the flowstone separates cultural layers traditionally labelled mousterian above and acheulean below the date reported here in association with other recent age determinations for mousterian and acheulean artifact assemblages in western europe calls into question the temporal significance of these archaeological designations in addition it further underlies the importance of the castillo cultural sequence and allows tentative discussion of changing rates of sedimentation in the vestibule of the cave where some 18 m of cultural and geological deposits were laid down during the course of the upper pleistocene

stratigraphy and sediment characteristics of a mesotidal ebb tidal delta north edisto inlet south carolina abstract ebb tidal deltas can form extensive strandline sand deposits on barrier island shorelines this paper describes the diagnostic textures sedimentary structures and geometry of an ebb tidal delta in a mesotidal setting at north edisto inlet south carolina bedforms and surface textures at north edisto inlet reflect typical ebb tidal delta circulation patterns the main ebb channel is dominated by large ebb oriented bedforms and channel sediments become finer grained in the seaward direction at the inlet throat the coarsest available sediment forms a lag deposit marginal flood channels adjacent to the barrier islands are dominated by floodoriented bedforms composed of medium grained sand channel margin linear bars flanked by bedforms with opposing orientations develop where flood channels approach the main ebb channel the extensive swash platform is dominated by wave energy which effectively sorts swash platform sediments ebb tidal delta stratigraphy is dominated by sequences deposited by shifting tidal channels and by the migration of swash bars on the swash platform proximally the ebb tidal delta sequence is dominated by relatively thick tidal channel deposits which fine upward and have a sharp disconformable lower contact main ebb channel deposits up to 20 m thick flank the active channel these deposits are composed primarily of well sorted planar bedded fine grained sand flaser bedded sands directly overlie medium to coarse grained seaward directed crossbedded sands at the base of the sequence adjacent to barrier islands marginal flood channel deposits dominate the ebb tidal delta sequence these are composed of moderately to intensely burrowed wavy to flaser bedded sand and mud barrier island accretion in the vicinity of inlets often involves flood channel switching marginal flood channel deposits could thus comprise a significant portion of the barrier island lithosome in the vicinity of inlets distally wave formed swash platform deposits dominate the ebb tidal delta sequence these are characterized by very well sorted fine grained sand planar bedding landward oriented crossbeds coarse shell hash layers and extensively burrowed zones swash platform deposits interfinger with shoreface deposits laterally and at depth distal ebb tidal delta deposits are thus relatively thin and have an overall coarsening upward grain size trend

marine transgression and regression in miocene sequences of northern pegu bago yoma central myanmar abstract neogene strata of the northern part of the pegu bago yoma range central myanmar contain a series of shallow marine clastic sediments with stratigraphic ages ranging from the early to late miocene the studied succession around 750 m thick is composed of three major stratigraphic units deposited during a major regression and four major transgressive cycles in the early to late miocene the transgressive deposits consist of elongate sand bars and broad sand sheets that pass headward into mixed flats of tidal environments marine flooding in transgressive deposits is associated with coquina beds and allochthonous coral bearing sandy limestone bands major marine regressions are associated with lowstand progradation of thick estuary point bars passing up into upper sand flat sand bodies encased within the tidal flat sequences and lower shoreface deposits with local unconformities the succession initially formed in a large scale incised valley system and was later interrupted by two major marine transgressions in the generally regressive or basinward stepping stratigraphic sequences successive sandbodies were formed during a sea level lowstand and early stage of the subsequent relative rise of sea level in a tide dominated estuary system in the eastern part of the central myanmar tertiary basin during early to late miocene times

urban geo archaeology in medieval alzira prov valencia spain abstract alzira is situated in a cut off meander loop of the rio jucar geo archaeological study shows that the islamic city wall was built during the second quarter of the 11th century ad at a time when the river had a low amplitude and low energy flood regime after mid century overbank silts began to invade the city as peak flood discharge increased with a spate of destructive floods reflected by high energy deposits during the late 11th century urban expansion within the city wall is dated to the later 11th or early 12th century interrupted by local abandonment and moderate energy flood silts major construction during the mid 12th century was followed by protracted abandonment after a siege in ad 1171 and further moderate energy flood silts that redistributed occupation and collapse debris reoccupation during the late 14th century was terminated by catastrophic floods in 1517 and 1571 after which much of the western end of alzira was not rebuilt following further flood catastrophes during the 17th century parts of the central walled city remained abandoned until the 19th century with new occupation atop flood sands of yet another disaster in 1864 the change in flood regime after 1150 was a result of deforestation of the watershed but progradation of a downstream tributary fan after 1517 created an unstable aggrading floodplain increasingly prone to severe flooding climatic anomalies were responsible for periods of recurrent severe floods archaeologically verified during the 11th and 12th centuries and historically documented beginning in 1318 the geo archaeological methodology illuminates the constructional and settlement history of alzira allows distinction of fluvial and cultural components and provides the necessary microstratigraphic detail and dating control to document the true complexity of alluvial processes during the last 1000 years

u series analyses of the lower travertine at ehringsdorf ddr abstract u series analyses have been made of travertine samples from the archaeological site at ehringsdorf weimar the lower travertine in which hominid remains were found yields apparent ages from 350 000 to 200 000 yr correlation between isotope ratios yields an age of about 230 000 yr one sample of the upper travertine gives and age of 111 000 47 000 yr both upper and lower travertines contain fauna and flora indicative of interglacial conditions the lower travertine was deposited during isotope stage 7 while the upper travertine may have been formed during isotope stage 5 this contradicts most earlier biostratigraphic studies which assigned both lower and upper travertines to stages of the eem interglaciation correlative with isotope stage 5 the fauna and flora of the lower travertine are significantly different from those of the upper travertine however and in some respects are transitional to those of the travertines of bilzingsleben which appear to be older yet

sedimentological and archaeological fabrics in palaeolithic levels of the south eastern pyrenees cova gran and roca dels bous sites lleida spain abstract the comparative study of sedimentary fabrics in relation to archaeological fabrics in various levels of the sites of cova gran de santa linya middle and early upper palaeolithic and the roca dels bous middle palaeolithic has made it possible to analyse the formation dynamics of the deposits and determine the extent of disturbance of the archaeological levels by natural processes to achieve this diagrams and two and three dimensional indices were calculated from the azimuth and dip angle of natural clasts and artefacts the results indicate that the sedimentary levels were formed mainly by planar fabric shape gravitational processes low depositional angles which differ notably from the archaeological fabrics they contain characterised by a greater degree of isotropy this difference in the fabrics would reflect human activity and indicates that the archaeological levels both in cova gran and roca dels bous have not been subject to significant natural modifications and are preserved in situ

a model for raw material management as a response to local and global environmental constraints abstract identifying the causes of visible changes in the archaeological record is one of the major goals of archaeological and anthropological research environmental shifts have been often suggested as one of the primary drivers of anthropological changes due to their impact on biotic resources considerably less attention has been given to changes in the availability of lithic raw materials if raw materials for tool production were available in constant predictable amounts then stability or slow shifts of technological strategies would be expected in the archaeological record however this is not the case in the iberian paleolithic even considering that some of the observed changes may be driven by culture setting or function in this paper we investigate the possibility of changes in raw material availability through the action of geodynamic processes which could have exerted selective pressures on the technological strategies employed by human populations this approach highlights the possible impact of environmental factors on human populations not just through food and habitat but also through geology the maritime climates of southwestern iberia are good candidates for such a connection because the region faced dramatic fluctuations between cold dry and warm wet periods during the late pleistocene with well documented impacts on biotic and geomorphic systems a link between environmental conditions and human tool making strategies is suggested by the correlation between cold climate during the last glacial maximum and an abrupt shift in lithic assemblages toward reliable technological strategies using the climatic conditions that define this reliable phase of upper paleolithic technology between 17 and 23 ka bp two climate driven scenarios are suggested for technological strategies in the iberian paleolithic a cold dry phase with restricted availability of raw materials favoring a technological shift towards reliability and a warm wet phase with greater raw material availability and a more flexible maintenance based lithic technology applying this reasoning to paleoenvironmental proxy records for southwestern iberia it is likely that numerous episodes of climate induced raw material stress occurred towards the end of the middle paleolithic and around the time of the middle upper paleolithic transition at present insufficient data exist to properly test this hypothesis but ongoing investigations at sites throughout portugal hold promise toward achieving this goal

experimental and functional analysis of late middle paleolithic flake cleavers from southwestern europe france and spain the presence of flake cleavers at the end of the middle paleolithic in the vasco cantabria region southwestern france and northern spain is one element of the variability in mousterian lithic industries in southwestern europe because the function of these tools has rarely been studied we undertook a use wear analysis of them in order to gain a better understanding of the technological characteristics of late middle paleolithic industries in this geographic zone we conducted a series of experiments using these tools for activities associated with the processing of animal and vegetal materials the experimental reference collection thus constituted was subject to a low power use wear analysis and served as the basis of our interpretation of the use wear traces present on the archaeological flake cleavers of several assemblages olha i and ii gatzarria el castillo these flake cleavers revealed similarities with the experimental pieces that were hafted and used for percussion to fell trees and divide carcasses these data allow us to discuss the role of functional and cultural factors in the development of this tool type

sea level fluctuations and the geometric variability of tide dominated sandbodies abstract this paper presents examples of various large tidal sandbodies from the eocene roda sandstone in the southern pyrenees and the late pleistocene and early holocene in the east china sea an attempt is made to summarize the geometric variability of these large tidal sandbodies in relation to the sediment supply and tidal discharge of the depositional system transverse sand bars were developed in low sinuosity high gradient channels with high influxes of coarse sediments and water from fluvial systems tidal point bars were formed in meandering low gradient estuarine channel where tidal influence was stronger and sediment was finer than those of the transverse sand bar a tidal delta complex was built up at the estuary mouth with an abundant sediment supply and an increased tidal discharge tidal sand ridges were formed when relict fluvial or deltaic sands were eroded and reworked by strong tidal currents during subsequent sea level rise since the sediment supply and the tidal discharge of the depositional system were closely related to the eustatic sea level change and basin subsidence i e the relative sea level change special attention will be given to the relationship between geometric variability of tidal sandbodies and the sequence stratigraphic framework in which various sandbodies occurred three orders of eustatic sea level fluctuations can be recognized the third order eustatic sea level cycle together with basin subsidence controlled the development of systems tracts and the occurrence of different tidal sandbodies such as estuary and tidal flat facies during the late stage of a lsw systems tract type 1 sequence or a sm systems tract type 2 sequence tidal point bar facies tidal delta facies or tidal sand ridge facies during a tr systems tract estuary facies during an early hs systems tract and fluvial sand bar facies in a late hs systems tract and the early stage of a sm or lsw systems tract there are also the fourth order and fifth order eustatic fluctuations which are superimposed on the third order eustatic changes and have important control on the build up abandonment and preservation of composite and single tidal sandbodies respectively since the deposition of tidal sandbodies is very sensitive to eustatic sea level changes recognition of various tidal sandbodies is important in sequence stratigraphy analyses of sedimentary basins and in the facies prediction of clastic sediments in basin modelling

characteristic trace fossils in nearshore to offshore sequences upper cretaceous of east central utah more than 20 trace fossil species occur in marine facies of the cretaceous star point and blackhawk formations in the book cliffs and wasatch plateau provinces of utah major genera include ancorichnus arenicolites aulichnites chondrites conichnus cylindrichnus medousichnus ophiomorpha palaeophycus planolites rosselia schaubcylindrichnus scolicia skolithos teichichnus teredolites and thalassinoides newly named taxa include ancorichnus capronus medousichnus loculatus and rosselia chonoides most trace fossils occur in characteristic albeit intergradational ichnofacies correlative with major lithofacies of regressive nearshore to offshore sequences the latter include foreshore foreshore shoreface transition shoreface and offshore facies landward facies are typified by clean well sorted well stratified sparsely burrowed sandstones seaward facies except where interrupted by hummocky bedded sandstones exhibit successively less pure less well sorted and stratified more intensely

palaeoecological context for the extinction of the neanderthals a small mammal study of stratigraphic unit v of the el salt site alcoi eastern spain abstract el salt is emerging as a reference site for the study of the extinction of neanderthal populations in the eastern iberian peninsula during mis 3 the small vertebrate assemblage analysed in this work is framed within this general objective and comes from stratigraphic unit v the most recent unit with human presence nearly 1300 small mammal remains have been studied in order to reconstruct the palaeoecological conditions of this debated period a total of seven rodents microtus arvalis microtus duodecimcostatus microtus cabrerae sciurus vulgaris arvicola sapidus eliomys quercinus and apodemus sylvaticus three insectivores talpa occidentalis crocidura sp sorex sp and one lagomorph oryctolagus cf cuniculus were identified palaeocological analyse points to drier conditions in the upper part unit v of the stratigraphic sequence supporting the hypothesis that an aridification scenario may have played a role in the disappearance of the neanderthal groups inhabiting this region of the iberian peninsula

settling in sahul investigating environmental and human history interactions through micromorphological analyses in tropical semi arid north west australia the pleistocene continent of sahul was first settled by people who arrived by watercraft from island south east asia about 50 000 years ago some of the oldest archaeological sites in sahul are located in the southern kimberley in northwest australia this area lies within the southern zone of influence of the tropical monsoon and thus has always been highly sensitive to changes in monsoon dynamics over time how these climatic changes have affected the colonisation and occupation of australia is an important research theme in australian archaeology this paper illustrates the contribution and challenges of micromorphology in deciphering palaeoenvironmental and anthropogenic markers in a still largely unexplored australian context micromorphological analysis of two archaeological sequences in the napier range carpenters gap 1 and 3 provides a complementary and comprehensive reconstruction of the human climate history in this area spanning nearly 50 000 years of australian human presence the results demonstrate an opportunistic use of sites by people through time surprisingly independent of local climatic variation suggesting highly flexible subsistence strategies

saharan dust transport and high latitude glacial climatic variability the alboran sea record millennial to submillennial marine oscillations that are linked with the north atlantic s heinrich events and dansgaard oeschger cycles have been reported recently from the alboran sea revealing a close ocean atmosphere coupling in the mediterranean region we present a high resolution record of lithogenic fraction variability along images core md 95 2043 from the alboran sea that we use to infer fluctuations of fluvial and eolian inputs to the core site during periods of rapid climate change between 28 000 and 48 000 cal yr b p comparison with geochemical and pollen records from the same core enables end member compositions to be determined and to document fluctuations of fluvial and eolian inputs on millennial and faster timescales our data document increases in northward saharan dust transports during periods of strengthened atmospheric circulation in high northern latitudes from this we derive two atmospheric scenarios which are linked with the intensity of meridional atmospheric pressure gradients in the north atlantic region

a late pleistocene coarse grained spit platform sequence in northern jylland denmark several well preserved late pleistocene spit systems occur uplifted in northern jylland denmark their present day morphological expression allows detailed study of spit growth patterns while the internal sedimentological organisation can be examined in a series of pits distributed along the length of the spits two characteristic vertical sequences are recognized in the systems the first sequence i consists of a giant scale cross bedded foreset unit overlain by topset and beach units while the second sequence ii consists of the foreset unit overlain by bar trough and beach units the two sequence types pass laterally into each other with a short overlap zone they can be interpreted in terms of meistrell s 1966 1972 model for spit platform growth based on scaled wave tank experiments the giant scale cross bedded unit corresponds to prograding of a coarse grained subaqueous spit platform while the topset bar trough and beach units reflect the growth of the subaerial spit the alternation between sequence i and ii reflects the inversely related growth of the spit and platform structures when the rate of subaqueous platform progradation declines the subaerial spit grows uniformly and when the platform progrades uniformly spit growth declines the model is probably only valid for relatively coarse grained systems because only these deposits would have a relatively steep front the water depth in which the spit system progrades and thus bottom topography determines the thickness of the giant scale cross bedded foreset unit because the water depth over the top of the platform is relatively constant if the water is less than a few metres deep the spit platform is not developed as seen where the late pleistocene spit systems prograded over elevations of the sea bottom conversely the correct recognition of spit platform sequences allows precise determination of sea level and water depth at the time of formation finally the model adds one further mode of formation of giant scale cross bedding to those already known from fluvial transverse lateral and point bars subtidal sand waves and gilbert deltas

tidal bundle sequences in the jordan sandstone upper cambrian southeastern minnesota u s a evidence for tides along inboard shorelines of the sauk epicontinental sea abstract this study documents for the first time tidal bundling in a lower paleozoic sheet sandstone from the cratonic interior of north america providing insights into the hydrodynamics of ancient epicontinental seas the jordan sandstone upper cambrian in the upper mississippi valley contains large scale planar tabular cross sets with tidal bundle sequences which were analyzed in detail at an exceptional exposure tidal bundle sequences neap spring neap cycles were delineated by foreset thickening thinning patterns and composite shale drapes the latter of which represent accumulations of mud during the neap tides of neap spring neap tidal cycles fourier analysis of the bundle thickness data from the 26 measurable bundle sequences revealed cycles ranging from 15 to 34 bundles per sequence which suggests a semidiurnal or mixed tidal system along this part of the late cambrian shoreline we extend the tidal interpretation to widespread occurrences of the same facies in outcrops of lesser quality where the facies is recognizable but too few bundles are exposed for tidal cycles to be measured by doing so this study shows that tidally generated deposits have a significant geographic and temporal extent in upper cambrian strata of central mid continent north america the deposition and preservation of tidal facies was related to the intermittent development of shoreline embayments during transgressions the tidally dominated deposits filled ravined topographies that were repeatedly developed on the updip parts of the shoreface resulting coastal geomorphologies accompanied perhaps by larger scale changes in basinal conditions and or configuration led to changes in depositional conditions from wave dominated to tide dominated outcrops of the jordan sandstone tidal facies in the upper mississippi valley represent the farthest inboard recorded transmission of ocean generated tides in the laurentian epicontinental seas demonstrating that tidal currents were significant agents in the transport of sand along the far cratonic interior shorelines of cambrian north america the results of this study improve the facies level understanding of the genesis of sheet sandstones furthermore tidalites documented here occur in a specific position within a sequence stratigraphic architecture for the jordan sandstone this provides a framework to compare these ancient deposits and processes to younger e g carboniferous epicontinental systems where stratal and sediment dynamics are better documented

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