desert agricultural systems at eba jawa jordan integrating archaeological and paleoenvironmental records located in the arid basalt desert of northeastern jordan the settlement of jawa is by far the largest and best preserved archaeological site in the region the early bronze age eba settlement phase of jawa 3500 3000 bce is characterized by a highly sophisticated water storage system made of a series of pools dams and canals in addition recent archaeological and geoarchaeological surveys have uncovered agricultural terrace systems in the nearby vicinity in this study four of these runoff terrace systems were investigated by detailed mapping additionally thirteen sediment profiles from inside and outside the terrace systems were recorded and sampled the examined samples were analyzed for bulk chemistry texture phytoliths diatoms and dung spherulites to supply information on the environmental and depositional conditions the terrace systems were dated using optically stimulated luminescence osl ancient terrace agriculture was practiced on slopes small plateaus and valleys close to jawa through the use of surface canals which collected and diverted floodwater from nearby wadis or runoff from adjacent slopes the terraced fields were usually arranged in cascades and comprised a system of risers canals and spillways the terrace fills investigated yield osl ages of around 3300 bce indicating that the terraces were constructed in the early bronze age the terrace fill sequences are composed of mixed unstratified fine sediments of local origin reflecting low energy fluvial deposition regimes the phytolith record is dominated by pooid grasses that include the most common near eastern cereals such as wheat and barley increased phytolith concentrations in terrace fill sediments as compared to samples from non terrace deposits nearby suggest increased plant growth and water availability within the terraces whether the terrace systems were used for growing food crops only or whether they were additionally used for grazing cannot be ascertained overall quantitative phytolith analyses in arid environments are well suited to investigate temporal and spatial distributions of plant microfossil concentrations and their relation to human activity or paleoenvironmental conditions

cosmic ray labeling of erosion surfaces in situ nuclide production rates and erosion models a number of in situ cosmogenic radionuclides and stable nuclides have been measured in natural exposed rock surfaces with a view to study their in situ production and rock erosion rates 1 the in situ radionuclides can be used for a high resolution tomography of the erosional history of an exposed surface two stable nuclides 3he 21ne and five radionuclides 10be 26al 36cl 14c 39ar having half lives in the range of 300 1 5 106 yr half life are measurable in many rock types a prerequisite for the application of the in situ nuclides for the study of erosional histories of surfaces is a knowledge of their production rates under different irradiation conditions altitude latitude irradiation geometry and shielding relative nuclide production rates can be determined fairly accurately using the extensive available data on cosmic ray neutrons 2 absolute nuclide production rates cannot generally be predicted with any accuracy because of lack of data on excitation functions of nuclides unless some normalization is possible as was done in the case of several cosmic ray produced isotopes in the atmosphere 3 based on a recent natural calibration experiment in which erosion free surfaces exposed to cosmic radiation for 11 000 yrs were sampled the absolute production rates of 10be and 26al in quartz have been accurately estimated for mountain altitudes in sierra nevada 4 the absolute production rates of 10be and 26al in quartz can therefore be estimated fairly accurately for any given latitude and altitude some measurements of 14c in rocks of low erosion rate 5 similarly allow an estimate of its production rate attempts made to measure the in situ production rates of 3he in rocks have not yet led to a convergent production rate in view of the importance of knowing the production rates of isotopes of he ne and ar i present here theoretical estimates of their production rates based on available cross section data i discuss the information that can be extracted from the study of the in situ nuclides in rocks useful parameters characterizing the exposure history of a rock surface are 1 the effective surface exposure age and 2 the time averaged erosion rate the implications of these parameters for single and multiple nuclide studies are discussed in terms of the erosion models considered

the eurogeul first report of the palaeontological palynological and archaeological investigations of this part of the north sea abstract the eurogeul is the shipping lane gully in front of rotterdam harbour due to the combination of suction dredging and fishing activities diverse faunae are found on its bottom this paper briefly describes the fauna consisting of 13 terrestrial mammals and six marine mammal species radiocarbon dating gave two time periods from which the bones originate ca 37 500 48 500 bp and ca 7 8000 bp pollen sampling gave similar results respectively an interstadial before the last glacial maximum and the early holocene boreal period human artefacts dating from the boreal period add to our understanding of the quaternary history of the southern north sea area

preservation potential for late quaternary river alluvium valley sequences of late quaternary alluvial units reflect alluvial preservation as well as alluvial production factors effects of lateral channel migration incision aggradation and channel stability on preservation potential are explored and then considered in the light of 14 available data sets cartographically dated and model data based on lateral channel migration well mapped and dated late quaternary valley unit surveys and composite age frequency plots for dated alluvial units and flood sediments despite much expectable variation between sites and the complex effects of river activity combinations a common characteristic of the data sets examined is the significance of preservation factors lateral migration tends to eliminate older units as it creates new alluvial deposits whereas incision may lead to the preferential preservation of older units beyond the incision slot aggradational environments are likely to preserve more complete records although simultaneous lateral migration may eliminate possibly repeatedly the upper parts of alluvial units the common pattern of inset and incised streams within pleistocene and early holocene fills or bedrock gives finite extent to later units within narrowing valleys so that development of new valley floor units is necessarily at the expense of reprocessing earlier ones floods associated with both slack water deposits and berms are also responsible for the removal of accessible earlier materials thus limiting the preserved record of earlier events in light of these censoring effects of river activities the sequence of preserved late quaternary units within uk sequences is reconsidered it is concluded that preservation potential factors have led to spatial and temporal bias in the alluvial record and that both here and elsewhere preservation potential needs to be considered systematically alongside variable sedimentation resulting from allogenic environmental factors when interpreting the alluvial archive copyright 2003 john wiley sons ltd journal of quaternary science

impact of climate and humans on the range dynamics of the woolly mammoth mammuthus primigenius in europe during mis 2 the woolly mammoth mammuthus primigenius was widespread in almost all of europe during the late pleistocene however its distribution changed because of population fluctuations and range expansions and reductions during marine oxygen isotope stage 2 mis 2 these processes were highly dynamic our analyses of 318 radiocarbon dates from 162 localities obtained directly from mammoth material confirmed important changes in mammoth range between 28 6 and 14 1 ka the greenland stadial 3 interval 27 5 23 3 ka was the time of maximum expansion of the mammoth in europe during mis 2 the continuous range was soon fragmented and reduced resulting in the disappearance of mammuthus during the last glacial maximum from 21 4 to 19 2 ka in all parts of the north european plain it is not clear whether mammoths survived in the east european plain the mammoth returned to europe soon after 19 0 ka and for the next 3 4 millennia played an important role in the lifeways of epigravettian societies in eastern europe mammoths became extinct in most of europe by 14 0 ka except for core areas such as the far northeast of europe where they survived until the beginning of the holocene no significant correlation was found between the distribution of the mammoth in europe and human activity

inbank and overbank velocity conditions in an arid zone anastomosing river relative to those at sub bankfull flow hydraulic conditions at overbank flow whether in the channel or on the floodplain are poorly understood here velocity conditions are analysed over an unusually wide range of flows in the arid zone river of cooper creek with its complex system of anastomosing channels and large fluctuations in floodplain width at a station hydraulic geometry relationships reveal sharp discontinuities in velocity at the inbank overbank transition the nature of the discontinuity varying with the degree of flow confinement and the level of channel floodplain interaction however despite inter sectional differences velocities remain modest throughout the flow range in this low gradient river and the large increases in at a station discharge are principally accommodated by changes in cross sectional area velocity distribution plots suggest that within channel conditions during overbank flow are characterized by a central band of high velocity which penetrates far toward the bed helping to maintain already deep cross sections floodplain resistance along cooper creek is concentrated at channel bank tops where vegetation density is highest and the subsequent flow retardation is transmitted across the surface of the channels over distances as large as 50 70 m the rough floodplain surface affects flood wave transmission producing significant decreases in wave speeds downstream the character of the wave speed discharge relationship also changes longitudinally from log linear in the upper reaches to nonlinear where the floodplain broadens appreciably the nonlinear form is similar in several respects to relationships proposed for more humid rivers with flood wave speed reaching an intermediate maximum at about four fifths bankfull discharge before decreasing to a minimum at approximately q2 33 it does not regain the value at the intermediate maximum until the 10 year flood by which time floodplain depths have become relatively large and broad floodways more active copyright 2002 john wiley sons ltd

a palaeoenvironmental reconstruction based on palaeobotanical data and diatoms of the middle pleistocene elephant palaeoloxodon antiquus butchery site at marathousa megalopolis greece abstract exposures of middle pleistocene lacustrine sediments at the margins of an open cast lignite mine at marathousa near megalopolis western arcadia greece yielded the partial remains of a palaeoloxodon antiquus skeleton which exhibited signs of being butchered sedimentation occurred between ca 400 and 480 ka lithic artefacts were found in close spatial and stratigraphic association with the elephant remains a palaeobotanical investigation involving carpological phytolith and wood remains as well as diatom analysis led to a detailed reconstruction of the local environment at the time of sediment deposition the results of this study enabled the environmental context of the butchering of the palaeoloxodon antiquus carcass to be established palaeobotanical data show that sediment deposition at the palaeoloxodon antiquus site occurred in shallow water in front of a reed swamp with trees in the immediate surroundings particularly alnus and salix on a flat plain where the water table was at or just below the ground surface warm conditions prevailed at the time of sediment deposition allowing aquatic plants typically recorded in the climatic optima of european interglacial assemblages to occur e g brasenia schreberi and palms palmae to live close by this suggests that the organic rich sediments that contain the archaeological finds represent a transition between the underlying clastic sediments deposited during colder conditions and the overlying lignite that was deposited during warm climatic conditions as reported in previous studies

landscapes depositional environments and human occupation at middle paleolithic open air sites in the southern levant with new insights from nesher ramla israel abstract middle paleolithic human occupation in the levant 250 50 ka ago has been recorded in roofed cave and rockshelter and open air sites research at these different types of sites yielded different perspectives on the middle paleolithic human behavior and evolution until recently open air middle paleolithic sites in the levant were found in three major sedimentary environments fluvial lake margin and spring here we describe a unique depositional environment and formation processes at the recently discovered open air site of nesher ramla israel and discuss their contribution to understanding site formation processes in open air sites in the levant the site is 8 m thick middle paleolithic sequence osl dated to 170 80 ka that is located in a karst sinkhole formed by gravitational deformation and sagging into underground voids the sedimentary sequence was shaped by gravitational collapse cyclic colluviation of soil and gravel into the depression waterlogging in situ pedogenesis and human occupation original bedding and combustion features are well preserved in the lower archaeological sequence a rare occurrence in comparison to other open air archaeological sites this phenomenon coincides with episodes of fast sedimentation burial which also allowed better preservation of microscopic remains such as ash the upper archaeological sequence does not exhibit bedding or preservation of ash despite presence of heat affected lithic artifacts which makes it similar to other open air sites in the levant we suggest that rate of burial is the major factor that caused the difference between the upper and lower sequences the differences in the burial rate may be connected to environmental and vegetation changes at the end of mis 6 we also identified an interplay between sediment in wash and density of human activity remains i e during episodes of low natural sediment input the density of artifacts is higher relative to episodes with high rate of sediment in wash the detailed analysis of natural and anthropogenic processes at nesher ramla suggests a much wider spectrum of processes than previously reported for southern levantine paleolithic sites nesher ramla shares certain depositional and post depositional characteristics with both cave and open air sites and provides a better insight into processes which control both types of sites

real and apparent changes in sediment deposition rates through time 1 field measurements show that estimated sediment deposition rate decreases as a power law function of the measurement interval this apparent decrease in sediment deposition has been attributed to completeness of the sedimentary record the effect arises because of incorporation of longer hiatuses in deposition as averaging time is increased we demonstrate that a heavy tailed distribution of periods of nondeposition hiatuses produces this phenomenon and that observed accumulation rate decreases as t 1 over multiple orders of magnitude where 0 1 is the parameter describing the tail of the distribution of quiescent period length by using continuous time random walks and limit theory we can estimate the actual average deposition rate from observations of the surface location over time if geologic and geometric constraints place an upper limit on the length of hiatuses then average accumulation rates approach a constant value at very long times our model suggests an alternative explanation for the apparent increase in global sediment accumulation rates over the last 5 million years

late pleistocene humans in sri lanka used plant resources a phytolith record from fahien rock shelter abstract little is known of the human use of rainforest plant resources of prehistoric sri lanka due to the lack of preservation of organic material and the effects of various destructive taphonomic processes phytoliths recovered from a ams radiocarbon and osl dated sequence at fahien rock shelter indicate interactions of anatomically modern humans with the lowland rainforests of south western sri lanka from 44 952 47 854 cal bp to 11 991 12 402 cal bp during this period the rock shelter occupants extracted their livelihood from a number of wild plants including bananas rice breadfruits durians canarium and species of palm and bamboo these taxa are associated with present day disturbed lowland rainforests gathering and processing of plant resources by existing modern rainforest foragers cannot directly be compared with the subsistence activities of the late pleistocene rock shelter occupants

chronological and palaeoenvironmental context of human occupations at the buendia rockshelter central spain during the late upper pleistocene in inland iberia ignacio de la torre et al article first published online 23 jun 2015 manuscript accepted 6 may 2015 manuscript revised 26 apr 2015 manuscript received 23 dec 2014

late quaternary aeolian and fluvial interactions on the cooper creek fan and the association between linear and source bordering dunes strzelecki desert australia abstract the innamincka dome and associated low gradient fan in the strzelecki desert is the product of cenozoic crustal warping that has aided formation of an extensive array of palaeochannels source bordering transverse dunes and superimposed linear dunes these dunes have impeded the course of cooper creek and provided a repository of evidence for quaternary climate change as well as the interactive processes between transverse and linear dune formation at turra gidgealpa and sites nearby are extensive fluvial and aeolian sand bodies that date from marine isotope stages mis 8 3 and the last glacial maximum lgm and are now surrounded or buried by overbank mud the sandy alluvium was deposited on the downstream slope of the dome by large channels transporting abundant bedload subsequently blown northward to form transverse dunes from what were probably seasonally exposed bars in a palaeo cooper system thermoluminescence tl and optically stimulated luminescence osl ages demonstrate that the base of the dune complex is at least mis 7 in age 250 ka but that it has been subsequently reworked by wind with additional sand blown from the river source bordering dunes formed during a period of enhanced river flow and sand supply from 120 to 100 ka with another short episode of the same at 85 80 ka and from 68 to 53 the lgm was associated with enhanced flows and the supply of dune sediment from 28 to 18 ka pronounced river flow and dune activity occurred in the early to mid holocene but there is no evidence of dunes being supplied from cooper creek since the lgm the dunes forming the oldest basal sand units appear to be largely transverse in form and are aligned roughly parallel to adjacent east west trending palaeochannels linear dunes have formed from and over these and yield basal ages ranging from mis 5 or mis 4 but continuing to accrete and rework through to the holocene the study results in one of the few detailed chronological investigations of the interaction between transverse and linear dunes it is apparent that long distance sand transport has played no significant role in dune formation here for the linear dunes show no significant downwind decline in ages linear dunes appear to have accreted vertically from underlying transverse dunes a wind rift vertical accretion model with only minor lengthwise extension is the dominant mode of linear dune formation in this section of the strzelecki desert the bulk of dune sediment being sourced from adjacent swales since the lgm

dissolution of biogenic silica from land to ocean role of salinity and ph the dissolution rates of diatom frustules phytoliths two diatomaceous lake sediments a siliceous ooze from the southern ocean a diatomite deposit and a synthetic amorphous silica were measured in flow through reactors supplied with either seawater or freshwater although the rates varied by more than one order of magnitude among the different siliceous materials for any given solid the rate was systematically higher in seawater than freshwater on average by a factor of five flow through reactor experiments with the diatom frustules and synthetic silica using mixtures of freshwater and seawater indicated that most of the rate increase occurred for seawater fractions between 0 and 50 the observed rate enhancement is attributed to the higher ph of seawater and the catalytic effect of seawater cations on the hydrolysis of siloxane bonds at the silica surface because of their abundance in seawater na and mg2 are mainly responsible for the salinity induced rate increase the large difference in dissolution kinetics between freshwater and seawater helps explain the very efficient recycling of biogenic silica in marine environments compared with freshwater lakes enhanced dissolution at the land ocean transition of biogenic silica produced by terrestrial plants and freshwater diatoms may represent a significant but largely overlooked source of nutrient silicon for estuarine and nearshore marine ecosystems

archaeological formation theory and geoarchaeology state of the art in 2016 since the influential work of michael b schiffer on formation processes has been published in 1987 much has advanced on the part of environmental formation processes also known as n transforms most new knowledge is the result of research conducted by geoarchaeologists on the theoretical level a huge leap forward was made with the realization that occupation deposits are artifacts of human activity the focus of formation theory thus shifted from the artifact to the deposit methodological innovations and a geoarchaeological tool kit notably including the contextual technique of micromorphology followed empirical studies of archaeological occupation deposits contributed new spatial and stratigraphic knowledge and understanding a holistic middle range methodology termed geo ethnoarchaeology was developed whereby macroscopic and microscopic artifacts are studied together with their associated sediments in ethnographic contexts providing contextual social information about the relationship between artifacts and the surrounding sediments as archaeological assemblages form this method is especially powerful when sequentially dated abandoned settlements or features are studied to provide mechanistic understanding of assemblage and or site formation through degradation because geo ethnoarchaeology is based on general chemical biological and physical laws the resultant mechanistic models are applicable globally for any time period culture and environment the new tools and mechanistic understanding by which n transforms are currently studied provide means to more reliably interpret the archaeological record which is crucial for the credibility of archaeology therefore when studying archaeological assemblages one should utilize the tool kit developed by geoarchaeologists to first assess the states of preservation of the various material assemblages macroscopic and microscopic as it should be borne in mind that assemblages identified to be well preserved will produce the most reliable archaeological interpretation the theory and method of geoarchaeology have matured enough to allow responsible archaeological research into the meaning of spatial and temporal stratigraphic patterns at any given site

phytolith rich layers from the late bronze and iron ages at tel dor israel mode of formation and archaeological significance the presence of many phytolith rich layers in late bronze and iron age deposits at tel dor israel are indicative of specific locations where plants were concentrated detailed studies of six of these phytolith rich layers and associated sediments from tel dor show that the phytoliths were derived mainly from wild and domestic grasses the most common domestic grass was the cereal triticum aestivum bread wheat three of these layers have a microlaminated microstructure associated dung spherulites and phosphate nodules characteristics that all point to the phytolith rich layers having formed from dung in animal enclosures in two of the layers the microlaminated structure is absent while dung spherulites and phosphate nodules are present suggesting that these too originate from dung that was not deposited in an enclosure the sixth layer is microlaminated but does not contain spherulites we thus cannot suggest a parsimonious explanation of its observed properties concentrations of burnt phytoliths are present in three locations implying that dung was either burnt in situ or the ashes from burnt dung were redeposited the transformation of dung accumulations into phytolith rich layers involves a loss of organic material and hence a significant reduction in sediment volume which is clearly apparent in the stratigraphy of some of the locations examined the volume reduction can be observed in the macrostratigraphy and has important implications with regard to macrostratigraphic interpretation the presence of abundant phytolith rich layers on the tell has significant implications for the concept of urbanism during these periods 2007 elsevier ltd all rights reserved

assessment of the 1 na2co3 technique to quantify the phytolith pool amorphous silica asi pool and fluxes have become parameters of a growing interest in the understanding of the biogeochemical cycle of si and the modeling of anthropogenic impacts extraction by 1 na2co3 followed by a correction for crystalline si demaster 1981 has recently become widely used and is proposed as the standard technique for quantifying amorphous silica asi pools in soil and continental aquatic environments however the 1 na2co3 method was developed to quantify diatom frustules and not phytoliths phsi which constitute the most common fraction of asi in soils the aim of this study was to assess the 1 na2co3 method for fresh and aged phytoliths we founded a significant positive correlation between si extracted by the 1 na2co3 method and si extracted by other standard procedures guntzer et al 2010 for various shoot samples elm horsetail fern and larch because the si shoot samples are mainly composed of phytoliths we concluded that the 1 na2co3 method was well adapted for the determination of phsi of fresh phytoliths containing less than 70 mg si g 1 to assess the 1 na2co3 method for phsi of aged phytoliths we used artificial mixtures of soil phytoliths from la reunion meunier et at 1999 and quartz our results showed that the 1 na2co3 method underestimated phsi for aged phytoliths by a factor of 3 7 combining the 1 na2co3 method and a physical method of extraction using samples of various origins showed a dispersion of the data that can be explained by a combination of several factors including loss during physical extraction and the presence of resistant phytoliths in the absence of standard technique we recommend to check the nature of the particles using physical extraction in combination with the 1 na2co3 in order to provide a more careful analysis of asi c 2013 elsevier b v all rights reserved

small scale spatial resolution of the soil phytolith record in a rainforest and a dry forest in costa rica applications to the deep time fossil phytolith record abstract phytolith analysis a well established tool in archaeology and quaternary paleoecology has become a source of data for deep time paleoecological studies only in the last 15 years recent years have also witnessed the publication of numerous soil phytolith inventories from extant vegetation types representing modern analogues however this work suffers from several methodological shortcomings limiting inter study comparisons and the development of a single and repeatable protocol for soil sample collection in this paper we focus on two fundamental methodological questions that must be answered before modern analogue studies can be meaningfully applied to deep time paleoecology 1 do phytoliths from the lower portion of the a horizon more commonly preserved in paleosols reflect standing vegetation equally well as the upper a horizon which is more commonly used in modern analogue studies but often truncated by erosion in paleosols 2 does a point soil sample usually collected from paleosols capture standing vegetation as accurately as a composite soil sample commonly used in modern analogue studies which is made from subsamples taken from a small area to address these questions we collected soil from 10 10 m quadrats in a rainforest la selva and a dry forest palo verde in costa rica and compared phytolith assemblages from upper vs lower soil a horizons and composites vs single phytolith assemblages at both sites phytolith assemblages from the lower vs upper a horizon and from single vs composite samples provide similar vegetation structure signal despite some compositional differences these results suggest that the typical approach in deep time paleoecology of taking point samples from the lower a horizon of paleosols is likely justifiable at least for paleosols reflecting rainforest and dry forest soils we discuss possible mechanisms driving differences between sites and future approaches to further expand and test our results

radiocarbon and mammoth bones what s in a date the radiocarbon dating method has developed into a reliable dating method for organic sample materials the latest calibration curve released enables numerical dating covering the complete dating range of the method however the category of fossil bones is the subject of discussion concerning validity of the dates in particular for the oldest part of the c 14 timescale this is a complex interplay of sample material integrity contamination issues and proper blanks in practice a safe upper limit for c 14 dates of bone material appears to be 45 000 bp 50 000 calbp c 2014 elsevier ltd and inqua all rights reserved

discovery of the skull of stephanorhinus kirchbergensis jager 1839 above the arctic circle the skull of the extinct rhinoceros stephanorhinus kirchbergensis jager 1839 was discovered in the chondon river valley arctic yakutia russia during the summer of 2014 this is the first find of stephanorhinus above the arctic circle expanding significantly the known geographic range of the genus 14 c dating and geologic evidence indicate that the skull dates to between 48 000 and 70 000 yr corresponding to marine oxygen isotope stage 4 3 it is thus among the latest records of this species to explore the evolutionary and natural history of this relatively unknown animal we performed morphological dietary and genetic analyses phylogenetic inference based on a complete mitochondrial genome sequence confirms the systematic placement of stephanorhinus as most closely related to the extinct woolly rhinoceros coelodonta food remains in the fossas of the cheek teeth identified as larix vaccinium betula sp aulacomnium and dicotyledonous herbs and grasses suggest a mixed feeder s diet microwear analysis suggests that during the last months of its life this individual fed predominantly on leaves and twigs the habitat of stephanorhinus comprised grassland and open woodland that were characterized by moist and cold climate conditions similar to those in the region today

the flk zinj paleolandscape reconstruction of a 1 84 ma wooded habitat in the flk zinj amk ptk ds archaeological complex middle bed i olduvai gorge tanzania abstract we have analyzed the phytolith content of 37 samples from the paleosol capped by tuff ic dated 1 84 ma within middle bed i at olduvai gorge tanzania samples were obtained from different trenches sampling an area of about 25 ha to document the paleovegetation associated with the abundant faunal remains and hominin artifacts in flk amk ptk and ds sites the analysis reveals the abundance of globular granulate and forest indicator phytoliths from 3 to 86 relative to the total number of phytoliths in the assemblages attributed to woody plants and of short cell grass phytoliths up to 22 the presence of palm phytoliths up to 57 attests for meso haline soils in the area in agreement with the presence of the saline alkaline olduvai paleolake and one or more groundwater discharge areas freshwater springs and or wetland phytoliths provide botanical evidence for a mixed paleovegetation dominated by forest and woodland with patches of open spaces occupied by grasses prior to the deposition of tuff ic the presence of fern phytoliths in some assemblages suggest shaded and humid habitat which supports the presence of freshwater watercourses or springs that might have attracted hominins and other animals yet we have found that our phytolith extractions residues also include micrometric zeolites chabazite clinoptilolite phillipsite which attest that the phytolith signal in the zinj paleosols is certainly affected by dissolution this study completes the spatial analysis of the area and reveals that the wooded area extends north south and west of flk zinj with palm trees preferentially located in the periphery like the zinj amk and ds sites the phytolith inferred distribution of plants does not support the hypothesis that topography was influential in the location of these sites particularly given that trees and or shrubs were dominant all over rather it is the presence of freshwater ponds that seem to have been the attractive factor for hominins at this particular place and time

the effect of progressive dissolution on the oxygen and silicon isotope composition of opal a phytoliths implications for palaeoenvironmental reconstruction abstract the 30 si and 18 o values of silica phytoliths precipitated in plants can be applied to palaeoenvironmental reconstructions this study examines the effect of partial dissolution of phytoliths on their isotopic compositions and physical characteristics specific surface area mean particle size and discusses problems with paleoclimate reconstructions using the 18 o and 30 si values of phytoliths that have been modified in soils dissolution experiments were conducted in batch reactors under a range of ph 4 10 and temperature 4 44 c conditions the 18 o and 30 si values of phytoliths behaved similarly as dissolution progressed with values increasing until the solutions were approximately 30 40 saturated with silicic acid during this phase the isotopic composition of the remaining silica was primarily affected by dissolution reactions that preferentially removed the light isotopes 16 o and 28 si partial dissolution resulted in phytolith 18 o values that were up to 3 9 higher and 30 si values that were up to 0 63 higher than unaltered material after 30 40 saturation is reached precipitation of new silica begins to reduce the 18 o and 30 si values of remaining silica despite a net dissolution the 30 si values of precipitated silica were determined by the 30 si value of silicic acid previously released by dissolution the 18 o values of precipitated silica were determined by the 18 o value of water and the temperature of the experiment silica precipitated in isotopic equilibrium with water acted to reduce phytolith 18 o values as the solution approached saturation in soil environments such reactions may result in a silica coating on the phytolith that has a 18 o value in equilibrium with soil water confounding paleoclimate estimates this study demonstrates that assessment of the extent of post depositional alteration of soil phytolith assemblages is essential prior to the use of their isotopic compositions in paleoclimate models

chronostratigraphy site formation processes and pollen record of ifri n etsedda ne morocco abstract the rock shelter of ifri n etsedda is located at the southern flank of the kebdana mountains north east morocco at an altitude of around 300 m a s l twenty one radiocarbon ages attest an occupation of the shelter between 10 0 and 6 0 ka cal bp comb decorated pottery also known from other late neolithic sites of the area suggest a later occupation the presence of both epipalaeolithic and neolithic deposits offers the opportunity to study the neolithic transition in the area although the ifri n etsedda deposits contain a short hiatus next to the ifri oudadane shelter west of the melilla peninsula it is one of the few sites in the area allowing this approach the paper combines stratigraphic sedimentological and micromorphological studies in order to reconstruct the complex site formation processes pollen analysis offers exciting insights into environmental change human land use and subsistence strategies a short overview about the artefact assemblage allows the reconstruction of occupation history and a first placement of the site within the archaeological context of the area the epipalaeolithic occupation seems to be clearly bipartite and the ongoing study of the lithic assemblage promises the possibility of further subdivision in the area for the first time discontinuities of the epipalaeolithic might be connected to early holocene rapid climate change events rcc the neolithic occurred at about 7 2 ka cal bp marked by the appearance of pottery perforated snails ovicaprides and cereals hunting gathering and the use of terrestrial molluscs still played an important role during the neolithic as the main occupation phase the late early neolithic between 6 7 to about 6 0 ka cal bp appears striking similarities to other contemporary sites such as el zafrin at the nearby coast and the mtlili open air sites within the lower reaches of the moulouya river suggest that ifri n etsedda is part of a larger settlement cluster providing particular adaptations to mountainous landscapes

the taphonomy and preservation of wood and dung ashes found in archaeological cooking installations case studies from iron age israel cooking installations are among the most abundant features in bronze and iron age archaeological sites in the southern levant yet until now their study has been mostly descriptive we present a study of 11 purported archaeological cooking installations from three different bronze and iron age sites in israel in which we deployed a variety of microarchaeological techniques we provide direct physical evidence based on fourier transform infrared ftir spectroscopy demonstrating that the archaeological installations were operated with temperatures as high as 900 c using this technique we also demonstrate that all the mud constructed installations studied by us were internally fueled and therefore should be identified as tannurs rather than the externally fueled tabuns we studied in detail the quantities of ash related microscopic remains including opaline phytoliths calcitic wood ash pseudomorphs and dung spherulites we show that phytolith morphotype analysis cannot distinguish between wood dominated and dung dominated fuel materials while a newly developed method that calculates the ratio of ash pseudomorphs to dung spherulites psr method makes such a distinction possible moreover we experimented with the effect of partial dissolution on fuel ash psr values and utilize the results to explain taphonomy and diagenesis associated with two types of archaeological cooking installations pebble hearths and baking ovens in addition we identified micromorphological criteria that can be used to assess whether ash deposits in or above a cooking installations are in situ and or disturbed taken together all lines of evidence used in this study indicate that wood was the major fuel material across time and space in the studied archaeological contexts while dung was a secondary source of fuel this observation also cross cuts different culture historical entities philistines canaanites israelites and egyptians in addition wood was preferred as fuel irrespective of environmental differences among the studied sites this study is yet another demonstration of the value of integrating microarchaeological techniques and approaches to traditional macroscopic archaeology

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

paleovegetation changes accompanying the evolution of a riverine system at the bk paleoanthropological site upper bed ii olduvai gorge tanzania abstract paleovegetation studies are essential to ecologically frame hominin evolution the analysis of the phytolith content of 22 paleosol samples collected along the vertical sequence of the channel containing the bk bell s korongo archaeological levels provided evidence of the paleovegetation that accompanied the evolution of the riverine system that formed this site 1 353 million years ago when climate was particularly arid the analysis reveals the abundance of forest indicator phytoliths 46 to 92 of the assemblages rare grass silica short cells and sedges phytoliths up to 15 of assemblages and palms up to 10 of the phytolith assemblages the vegetation of the bk fluvial system was therefore characterized by abundant woody plants it did not vary significantly diachronically in the period of time under scrutiny the alluvial paleovegetation corresponds well to the fluvial dynamic that formed bk including the presence of sterile samples recovered in areas where the water traction changed the soils frequently this spot of dense paleovegetation together with the fluvial watercourse in a paleolandscape likely dominated by sparse open vegetation could have been attractive seasonally for animals and hominins

does decreasing paraglacial sediment supply slow knickpoint retreat in four rivers in western scotland for which there is a well constrained record of relative base level fall the rate of postglacial bedrock erosion is quantifi ed by measuring the concentration of in situ cosmogenic 10be on strath terraces downstream of headward retreating knickpoints along channel gradients in 10be exposure age show two distinct trends upstream younging and constant age which we interpret as diagnostic of knickpoint retreat and diffusive transport limited incision respectively we show that bedrock channel incision and regional formation of strath terraces began shortly after deglaciation ca 11 5 ka and that knickpoint retreat rates peaked in the early to mid holocene erosion rates have since decreased by two orders of magnitude converging in the late holocene to low rates independent of stream power per unit channel area we infer this regional slowing in postglacial knickpoint retreat to be the result of the depletion of paraglacial sediment supply over the holocene leading to a defi ciency in tools for bedrock erosion our results imply that episodes of major fl uvial erosion may be in tune with glacial cycles and that sediment depletion following glacial interglacial transitions may be an important cause of bedrock erosion rate variations in rivers draining glaciated landscapes

why some alluvial rivers develop an anabranching pattern anabranching rivers have been identified globally but a widely accepted and convincing theoretical explanation for their occurrence has remained elusive using basic flow and sediment transport relations this study analyzes the mechanisms whereby self adjusting alluvial channels can anabranch to alter their flow efficiency sediment transport capacity per unit of stream power it shows that without adjusting channel slope an increase in the number of channels can produce a proportional decrease in flow efficiency a finding particularly relevant to understanding energy consumption in some braided rivers however anabranching efficiency can be significantly increased by a reduction in channel width as occurs when vegetated alluvial islands or between channel ridges form the counteracting effects of width reduction and an increasing number of channels can cause with no adjustment to slope an otherwise unstable system underloaded or overloaded to achieve stability as with other river patterns anabranching can be characterized by stable equilibrium or accreting disequilibrium examples copyright 2007 by the american geophysical union

14c activity and global carbon cycle changes over the past 50 000 years a series of 14c measurements in ocean drilling program cores from the tropical cariaco basin which have been correlated to the annual layer counted chronology for the greenland ice sheet project 2 gisp2 ice core provides a high resolution calibration of the radiocarbon time scale back to 50 000 years before the present independent radiometric dating of events correlated to gisp2 suggests that the calibration is accurate reconstructed 14c activities varied substantially during the last glacial period including sharp peaks synchronous with the laschamp and mono lake geomagnetic field intensity minimal and cosmogenic nuclide peaks in ice cores and marine sediments simulations with a geochemical box model suggest that much of the variability can be explained by geomagnetically modulated changes in 14c production rate together with plausible changes in deep ocean ventilation and the global carbon cycle during glaciation

geoarchaeological and palaeobotanical evidence for prehistoric cereal storage in the southern caucasus the neolithic settlement of goytepe mid 8th millennium bp this paper presents direct evidence for cereal storage by neolithic farmers in west asia storage features analyzed this study are circular clay bins that frequently occur at neolithic settlements 8th millennium cal bp in the southern caucasus we examined contexts and uses of clay bin features at the neolithic settlement of goytepe azerbaijan we analyzed biogenic microfossil evidence primarily from phytoliths and dung spherulites and the sediments of the clay bins through micromorphology in combination with their associated charred macrobotanical remains while phytoliths and charred botanical remains indicate direct remnants of stored plants mainly chaffs micromorphology and the analyses of faecal spherulites allow us to examine depositional and diagenetic processes of the archaeological sediments inside and outside these features as a result one of the clay bins was found to retain deposits at its base exhibiting high concentrations of grass phytoliths with relatively high proportions of inflorescences and low percentages of anatomically connected phytoliths in comparison with its upper fill deposits and areas outside of the bin these finds combined with the association of the two complete grinding stones inside the bottom of the bin suggest that the remains of cereal processing activities specifically dehusking may have been placed in the bin this interpretation is corroborated by the recovery of charred rachises and chaffs of wheat and barley as well as micromorphological observations that the bottommost fill of the bin consists almost entirely of grass phytoliths with few very small charcoal fragments and fine amorphous organic matter

the good the bad and the ugly evaluating the radiocarbon chronology of the middle and late upper paleolithic in the enisei river valley south central siberia abstract the 14 c record for the upper paleolithic in siberia has remained largely unevaluated and includes good bad and ugly dates too often researchers accept either all published dates or only those dates that tend to support proposed chronological hypotheses regardless of sample quality and association this article systematically evaluates all published 14 c dates including several newly obtained ams dates from middle and late upper paleolithic sites in the enisei river valley of south central siberia to establish a reliable chronology for the region and address the tempo of modern human dispersals in siberia during late pleistocene times the revised chronology indicates humans were present before and after the last glacial maximum but absent during this climatic event results also suggest that human population in the region may have increased during the oldest dryas

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

mammoths inside the alps during the last glacial period radiocarbon constraints from austria and palaeoenvironmental implications abstract this study examines remains of the woolly mammoth mammuthus primigenius found inside the austrian alps an area occupied by an extensive ice stream network during the last glacial maximum the data demonstrate that these cold steppe adapted animals locally migrated several tens of kilometers into alpine valleys radiocarbon analyses constrain the age of these fossils to the first half of marine isotope stage 3 documenting ice free conditions in major valleys at that time we also provide a list of all traceable austrian sites of mammuthus primigenius totaling about 230 localities compiled through 15 museums and collections in austria the vast majority of these findings are from the corridors of the danube and mur rivers and their tributaries and the adjacent loess covered foreland of the alps areas that were never ice covered during pleistocene glaciations

a comparison of three methods for the extraction of phytoliths from sediments abstract this paper compares three methods commonly used to extract fossil phytoliths from sediments a basic procedure using heavy liquid flotation and oxidation is compared with two other procedures across a range of sediment types commonly encountered in archaeological studies the three procedures are 1 a heavy liquid flotation method hlf 2 a burning method pow and 3 another heavy liquid flotation method hlfpol similar to hlf but adapted to allow the extraction of pollen and spores as well as phytoliths within a single process comparisons of the resulting output using these three techniques for phytolith extraction show that different methods can produce different results and therefore basic techniques should be modified according to the characteristics of the sediments for which they are used while all the techniques showed similarities in assemblage results there were problems associated with disaggregation and effective separation of light and heavy fractions in particular with the pow procedure the evidence suggests that morphotype selection occurred both within the physical sorting process and in the process of inverting slides to shed excess residue in both cases it is difficult to suggest a solution to the problem the results show clearly that the advantages gained by using the pow procedure are largely outweighed by the problems encountered with its use and because of possible size shape selection it is not recommended for general extraction procedures the heavy liquid flotation procedures on the other hand are shown to produce more concentrated residues with higher levels of clarity and less potential than the pow procedure for sample bias the use of a non toxic heavy liquid sodium polytungstate now allows the process to be used in relative safety it is recommended that analysts use heavy liquid flotation procedures with chemical treatments specific to sediment requirements

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

eocene vegetation and ecosystem fluctuations inferred from a high resolution phytolith record a thorough understanding of the ecosystem factors that can act as drivers of vegetation change an important factor for projecting impacts of future climate change requires adequately distinguishing between plant community changes that occur on the local scale or over ecological time scales and long term trends phytolith assemblages have the potential to provide this information but little work has been done so far to test their ability to do so in deep time we examined vegetation patterns inferred from phytoliths plant silica microfossils from a single section of the renova formation timberhills region montana dated to 39 2 3 ma late middle eocene the section is composed of fl uvial sediments overprinted by paleosols including alfi sols entisols inceptisols and composite paleosols phytolith assemblages from 27 paleosol samples were used to reconstruct a high resolution vegetation history for the area and were compared with paleosol data phytoliths are predominantly from forest plants and include tropical elements such as palms arecaceae and gingers zingiberales suggesting a paratropical forest the high resolution sampling records heterogeneous vegetation including shifts among closed forest moderately open forest forest gaps edges and woodland and grass dominated habitats grasses are interpreted as early open habitat plants tolerant of drier conditions but they appear to be replaced by forest vegetation with time resulting in poor correspondence between paleosol type and phytolith assemblage at some stratigraphic levels where paleosol morphology indicates a forest ecosystem and the phytolith assemblages indicate a changing grass forest mixture as a function of depth within the profi les this is the fi rst study that has used phytoliths to construct a high resolution record of vegetation from deep time and we demonstrate that dense sampling and multiproxy approaches to paleo environmental reconstruction are necessary to capture vegetation heterogeneity in time and across microhabitats

current issues in late middle palaeolithic chronology new assessments from northern iberia abstract the iberian peninsula plays a central role in the current debates on the middle upper palaeolithic transition and the neanderthal extinction this is largely due to the chronological data which some authors have suggested show a clear divide between northern iberia where the upper palaeolithic appeared as early as 36 5 ka 14c bp and southern iberia where the middle palaeolithic survived until ca 32 30 ka 14c bp or later the best example of this view is the ebro frontier hypothesis however there are chronological data in both northern and southern iberia that do not fit this pattern and some of the evidence supporting the ebro frontier hypothesis has been questioned in recent years this paper focuses on the chronology of the final middle palaeolithic of northern iberia where several assemblages have been found to post date the first upper palaeolithic in the region and be of a similar age to the final neanderthal occupations of the south in order to improve the chronological framework of the middle upper palaeolithic boundary in the northern iberian peninsula a radiocarbon dating program is focused on sites from both the cantabrian and mediterranean regions the first results of this program are presented in this paper new radiocarbon dates have been measured by two laboratories using a range of pre treatment methodologies these do not support a late middle palaeolithic in northern iberia

soil phytoliths as indicators of initial human impact on san cristobal island galapagos abstract i analyzed phytoliths from soil profiles on san cristobal island in the galapagos islands to determine whether historical human impact and recent vegetation dynamics are visible in the phytolith record i extracted phytoliths from soil samples taken from four test pits located at the village an abandoned field a forest and an active agricultural field all located within the former el progreso plantation ad 1860 1920 changes in the ratio of tree to grass phytoliths with depth in all four samples suggest changes in vegetation composition from forest to open vegetation dominated by grasses which reflects the removal of forest with colonization and the first permanent human occupation of the archipelago in the middle 19th century this paper shows that the changes in vegetation brought about by colonization and land clearing for plantations are documented in the soil phytoliths record and suggests that phytoliths can be used as an indicator of past vegetation change in future work on the historical ecology of the galapagos archipelago

chronology and formation processes of the middle to upper palaeolithic deposits of ifri n ammar using multi method luminescence dating and micromorphology abstract the existence of an early upper palaeolithic culture at the transition from the middle palaeolithic to the upper palaeolithic in north african cave sites is currently under debate we studied ifri n ammar in north east morocco which is one of the oldest settlement sites of anatomically modern humans amh in the maghreb and contains several sediment layers which are attributed to middle and upper palaeolithic occupations in order to investigate processes of sediment accumulation and postdepositional alteration we studied thin sections from these levels according to micromorphological analysis aeolian input considerably contributed to sediment accumulation and postdepositional mixing by bioturbation occurred we compared multiple and single grain quartz and multiple grain feldspar luminescence dating of three samples from corresponding sediment layers to achieve a comprehensive chronology the single grain dose distributions scatter strongly and the source of the scatter is unclear we used an arithmetic mean to calculate the equivalent doses archaeological evidence and age control from radiocarbon dating was essential to interpret the data quartz and feldspar multiple grain luminescence ages are between 15 and 80 ka the central part of the profile shows an intermediate accumulation which lacks specified lithic artefacts this supports the idea of an occupational gap between middle and upper palaeolithic layers

preservation of anthropogenic materials under different geochemical processes a mineralogical approach minerals that are preserved or formed inside the sediment or soil can be used to determine whether primary anthropogenic constituents bones phytoliths organic matter charcoal etc would have been affected by diagenesis stability diagrams of the minerals that describe the chemical system under investigation can be constructed and then tested in the field in this approach it is assumed that the stability of the archaeological material of interest is known except for bone there are not many studies on the stability of other archaeological materials this approach does not provide information on the former presence of an archaeological material in the sediment or soil but only whether these materials are stable in such an environment some indirect indication may be provided by unique mineral associations but much more has to be done in this direction

lowland river responses to intraplate tectonism and climate forcing quantified with luminescence and cosmogenic 10be intraplate tectonism has produced large scale folding that steers regional drainage systems such as the 1600 km long cooper ck en route to australia s continental depocentre at lake eyre we appl

fluvial response to tectonic activity in an intra continental dryland setting the neales river lake eyre central australia abstract geomorphological studies in the centre of the australian continent have emphasised the antiquity of the australian landscape typically considered tectonically stable evidence from the neales river on the western shore of lake eyre indicates that mild epeirogenic forces have deformed sediments of miocene age deformed bedding planes small scale folds and fracture systems reflect consistent miocene and younger tectonic activity in central and southern australia this compression was mild resulting in broad gently plunging folds these folds are evident in the miocene strata but not in the overlying quaternary strata elsewhere in the study area the landscape has been rearranged to preserve features in the geomorphic record that indicate a second phase of tectonic activity in the early to mid pleistocene these include stream diversions preserved on alluvial fans and floodplains formed downstream of faults

functional relationships between vegetation channel morphology and flow efficiency in an alluvial anabranching river 1 water and sediment flux interactions are examined in magela creek an alluvial anabranching sand bed river in the northern australian tropics dense riparian vegetation stabilizes the channels and floodplains thereby preventing erosional instability at flow depths up to 6 2 times bankfull and discharges up to 15 times bankfull narrow anabranching channels characterize 92 of the alluvial reach and transport bed load more efficiently than short reaches of wide single channels yet overall 29 12 of the bed load is sequestered and the average vertical accretion rate is 0 41 0 17 mm yr 1 along the 12 km study reach the most effective discharge for transporting sediment 40 45 m3 s 1 is consistent at all 5 stations 10 channels examined and is equivalent to the channel forming discharge it has an average recurrence interval of 1 01 years occurs for an exceptionally long portion 13 15 of the annual flow duration and averages a remarkable 2 1 times bankfull the high flow efficiency i e bed load transport rate to stream power ratio of the anabranches is facilitated by low width depth channels with banks reinforced by vegetation colonnades of bank top trees confine high velocity flows overbed i e over the channel bed at stages well above bankfull at even larger overbank flows momentum exchange between the channels and forested floodplains restrains overbed velocities in some cases causing them to decline thereby limiting erosion magela creek exhibits a complicated set of planform cross sectional and vegetative adjustments that boost overbed velocities and enhance bed load yield in multiple channels while restraining velocities and erosion at the largest discharges

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

cainozoic stratigraphy palaeoenvironments and geological evolution of the lake eyre basin abstract for a large part of inland australia weathering and erosion prevailed from the cenomanian to the late paleocene subsidence commencing in the late paleocene produced a depocentre the lake eyre basin in which sedimentation occurred in three main phases 1 fluviolacustrine sand silt clay and carbonaceous horizons from latest paleocene to middle eocene 2 dolomite and magnesium rich clay and sand deposited in extensive shallow alkaline lakes from latest oligocene miocene and 3 red clay silt and sand were deposited in fluvial lacustrine and aeolian settings during the pliocene and quaternary widespread weathering and silicification of sediments occurred in the late eocene oligocene and again in the pliocene the latter also accompanied by ferruginisation the silcrete sheets were folded into broad domes during the oligocene and again in the pliocene when faulting marginal to the southern ranges also occurred from the late paleocene to early eocene the basin supported rainforest growing in megathermal to mesothermal conditions by the middle eocene vegetation had changed to localised riparian forest in valley bottoms and more open sclerophyllous woodland in the hinterland indicating monsoonal conditions for most of this early tertiary interval deposition was by broad braidstreams flowing northwards in the miocene scattered elements of megathermal forest still existed but open woodland was far more extensive strong climatic seasonality and elevated temperatures promoted the deposition of thick dolomites in giant alkaline lakes the lakes and the diverse vegetation were home to a rich aquatic and terrestrial fauna by the pliocene climate was semiarid and vegetation mainly open casuarinaceae dominated woodland with very rare stands of forest confined to edaphically suitable sites increasing aridity during the quaternary was punctuated by pluvial intervals vast lakes formed during the interglacials largely as a result of higher rainfall in queensland drier windier conditions during the glacials particularly the last led to the development of extensive dunefields

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

ams radiocarbon dating of middle and upper palaeolithic bone in the british isles improved reliability using ultrafiltration recent research at the oxford radiocarbon accelerator unit orau has shown that ultrafiltration of gelatin from archaeological bone can in many instances remove low molecular weight contaminants these can sometimes be of a different radiocarbon age and unless removed may severely influence results particularly when dating bones greater than two to three half lives of 14c in this study this methodology is applied to samples of late middle and early upper palaeolithic age from the british isles in many instances the results of redating invite serious reconsideration of the chronology for these periods copyright 2006 john wiley sons ltd

bedrock incision rock uplift and threshold hillslopes in the northwestern himalayas the topography of tectonically active mountain ranges reflects a poorly understood competition between bedrock uplift and erosion dating of abandoned river cut surfaces in the northwestern himalayas reveals that the indus river incises through the bedrock at extremely high rates 2 12 mm yr 1 in the surrounding mountains the average angles of hillslopes are steep and essentially independent of erosion rate suggesting control by a common threshold process in this rapidly deforming region an equilibrium is maintained between bedrock uplift and river incision with landsliding allowing hillslopes to adjust efficiently to rapid river down cutting

the role of phytolith formation and dissolution in controlling concentrations of silica in soil solutions and streams abstract by integrating the results of recent studies on the concentration and flux of si in european forest soils podzols and acid brown soils with published evidence on the amounts of si cycled through forest vegetation we conclude that phytoliths must be the principal immediate source and sink of silica in soil solution although mineral weathering is the ultimate source during the growing season forest vegetation takes up most of the si made available by weathering of soil minerals and by phytolith dissolution and converts it into phytoliths phytoliths will be the principal source of si leached from the soil during winter rains and spring snowmelt this work accounts for the plateau concentrations of si observed in laboratory equilibrations of bs horizon soils for the maximum si concentration reported for b horizons in the field for a deep sink for si in bs horizons and for the fact that the concentrations of si in soil drainage water and in streams all fall in or below the range expected for phytolith solubility concentrations of si in surface horizons can exceed these levels during droughts the common assumption that the concentration of si in soil solution is a result of a dynamic balance between si released by mineral weathering and that lost by leaching is untenable for bs horizons

palaeovegetation changes recorded in palaeolake olduvai ogcp core 2a 2 09 2 12 ma naibor soit formation olduvai gorge tanzania abstract for five decades olduvai gorge has been a key site to reconstruct and understand the relationship between environmental and landscape conditions and use of affordances by early african hominin populations following the first olduvai gorge coring project ogcp during 2014 a multiproxy microbiological analysis which includes phytoliths pollen diatoms sponge spicules and chrysophyte cysts was undertaken on samples collected from various borehole cores the aim of the study is to better understand palaeoenvironmental and palaeovegetation conditions and changes through time and their relationship to hominin presence and evolution this study details the first palaeobotanical and palaeoenvironmental study of borehole 2a at olduvai gorge it represents the as yet oldest known sedimentary sequence in the olduvai basin for a portion of the pre bed i naibor soit formation this is a unit that is not accessible in any natural exposures in olduvai gorge and has only recently been encountered by drilling here we present the results from a particularly phytolith prone portion between 2 09 ma and 2 12 ma phytolith results indicate a savannah environment dominated by grasses where poaceae were a key component and where the c3 pooideae grasses were mostly dominant alternating with c4 grasses oscillations between grass subfamilies c3 pooideae c4 chloridoideae and c4 panicoideae to lesser degrees indicate five substantial climatic shifts varying between more humid and arid conditions associated with phytoliths freshwater indicators such as diatoms sponge spicules and chrysophyte cysts were also identified suggesting the presence of wetlands in the lake catchment area pollen is extremely rare in the sediments but when present comprises fungal spores and poaceae pollen thus supporting the wetland and grassland reconstructions respectively these results offer for the first time a whole picture of the palaeovegetation and associated palaeoenvironments for this pre bed i period together with previous results from other areas and chronological periods they improve our understanding of the evolution and adaptation of early hominins and their close relationship to the surrounding landscape

phytolith and carbon isotope evidence for late quaternary vegetation and climate change in the southern black hills south dakota abstract analyses of phytoliths and carbon isotopes document change in late quaternary grasslands in the red valley of the southern black hills late pleistocene grassland composition was equivalent to the c3grass parklands of modern central alberta the rise of mixed grassland occurred rapidly between 11 000 and 9000 yr b p early holocene mixed grasslands included both short and tall c4grasses a mid holocene erosional unconformity ca 8000 to 4500 yr b p precludes phytolith or isotope analysis but suggests lack of vegetation and landscape denudation caused by a drier climatic basin wide stability and soil development followed the erosional episode ca 4500 to 3600 yr b p mesic adapted c4panicoid grasses increased during this period of soil development low magnitude fluctuation in the c4 dominated mixed grassland occurred throughout the late holocene 3600 yr b p to present rise in 13c values during the last 1000 yr without corresponding change in phytoliths may indicate a decrease in woodlands caused by increased fire frequency

taphonomy of phytoliths and macroplants in different soils from olduvai gorge tanzania and the application to plio pleistocene palaeoanthropological samples the abundance and types of phytoliths in the fossil record are taphonomically biased and do not correspond with the macroplant record to better understand the bias and improve the interpretation of samples from olduvai gorge tanzania we analysed the phytoliths from three sample sets modern grasses sedges palm and dicots in the area modern soils in the area and the fossil soils from the eastern palaeolake margin in lowermost bed ii fourier transform infrared spectrometry analyses were performed in parallel to compare the mineral composition of both modern soils and fossil soils we found that the abundance of phytoliths is greatly reduced in soil samples compared with modern plant material but the morphotypes can be reliably interpreted dicotyledonous wood bark phytoliths appear to be over represented in the soil types grass phytoliths and sedges to a lesser degree are preserved in the soils but in lower abundances resulting in these groups being under represented the macroplant fossils are fragments of grass and sedge aerial culms and dicotyledonous stems that are preserved in fluvial and lacustrine deposits it is suggested that phytoliths represent the continuous flora whereas macroplant fossils represent the more robust tissues of selected plants preserved under more catastrophic conditions a post depositional model is proposed and the palaeovegetation is reinterpreted as being richer and more complex than indicated by other fossil data

the 9th century bce destruction layer at tell es safi gath israel integrating macro and microarchaeology abstract destruction events in multi period sites are valuable marker horizons that represent time synchronous events across the site and sometimes between sites destruction layers often preserve rich finds that provide insights into site use here we use both macro and microarchaeological methods to study a destruction event from the late 9th century at tell es safi gath in israel a major conflagration at this specific location resulted in the consolidation of parts of the roof construction materials thus enabling us to differentiate between roof walls and floor materials we could reconstruct the events which lead to the formation of an approximately 80 cm thick layer the base of this layer that overlies the floor surface is a thin charred organic material rich ash layer as the clays in this layer were not altered by heat and the ceramics still have preserved residues we conclude that the ash was produced elsewhere and was redistributed to this location ceramics that are associated with burnt roof sediments do not have preserved residues we also estimate the time that each of the accumulation events might have taken and conclude that this accumulation occurred over decades the architecture and artifacts found within and beneath the destruction do not allow us to unequivocally identify the function of this area prior to destruction we do however identify an unusual bin and associated stone pavement and a corner rich in artifacts phytoliths and charred organic material we also show that a wall was built of fired mud bricks a most unusual occurrence for this time period in the levant this study demonstrates well the usefulness of an integrated macro and microarchaeological approach to understanding the archaeological record as well as the benefits of using an on site laboratory

response of alluvial rivers to slow active tectonic movement alluvial rivers respond to valley slope deformation caused by active tectonics in various ways depending on the rate and amount of surficial deformation and on the type of river on the basis of experimental results and field examples hypothetical models of river response to anticlinal uplift and synclinal subsidence were developed for different types of alluvial rivers an experimental braided channel responded to anticlinal uplift across the channel with degradation and terrace formation in the central part of the uplift with subsidence aggradation in the central reach was the main response transverse bars developed downstream of the subsidence axis an experimental meandering channel responded to slope steepening with a sinuosity increase bank erosion and point bar growth occurred downstream of the anticlinal axis and upstream of the synclinal axis upstream of the uplift axis and downstream of the subsidence axis where the slope was flattened water flooded over bars local convexity in longitudinal profiles of the middle rio grande new mexico is considered to be formed by a domal uplift local aggradation and degradation could be explained by the effect of uplift the san joaquin river california which is now highly controlled does not show clear adjustment to the rapid subsidence due to ground water withdrawal it shows however a channel pattern adjustment to active tectonic subsidence that has been occurring for a long time the san antonio and guadalupe rivers in texas both increase their sinuosity significantly where monoclinal movements steepen valley slopes

alluvial evidence for major climate and flow regime changes during the middle and late quaternary in eastern central australia as a low gradient arid region spanning the tropics to the temperate zone the lake eyre basin has undergone gentle late cenozoic crustal warping leading to substantial alluvial deposition thereby forming repositories of evidence for palaeoclimatic and palaeohydrological changes from the late tertiary to the holocene auger holes and bank exposures at five locations along the lower 500 km of cooper creek a major contributor to lake eyre in the eastern part of the basin yielded 85 luminescence dates tl and osl that combined wit a further 142 luminescence dates from northeastern australia have established a chronology of multiple episodes of enhanced flow regime from about 750 ka to the holocene mean bankfull discharges on cooper creek upstream of the innamincka dome at 250 230 ka or oxygen isotope stages ois 7 6 are estimated to have been 5 to 7 times larger than those of today however substantially less reworking has occurred during and after ois 5 than before lower cooper creek appears to have similarly declined in the tirari desert adjacent to lake eyre there is evidence of widespread alluvial activity perhaps during but certainly before the middle pleistocene yet the river became laterally restricted in ois 7 to 5 while the quaternary has been characterised by a dramatically oscillating wet dry climate since oxygen isotope stage ois 7 or 6 there has been a general decline in the magnitude of the episodes of wetness to which the eastern part of central australia has periodically returned during the last full glacial cycle cooper creek s periods of greatest runoff and sand transport were not during the last interglacial maximum of ois 5e 132 122 ka but later in ois 5 when sea levels and global temperatures were substantially below those of 5e or today fluvial activity returned in ois 4 and 3 but not to the extent of mid and late ois 5 strongly seasonal but still powerful flows transported sand and fed source bordering dunes in ois 5 and 3 this chronology of fluvial activity in the late quaternary broadly coincides with that for rivers of southeastern australia and suggests that the wet phases in eastern central australia have not been governed as much by the northern monsoon as by conditions in the western pacific close to the east coast both north and south flow confinement within the innamincka dome has locally amplified cooper creek s energy and here evidence exists for short but high magnitude episodes of flow during the last glacial maximum and in the early to middle holocene conditions that were capable of forming large palaeochannels but that were not long lived enough to rework the river s extensive floodplains elsewhere along its length

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

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

when the carbon being dated is not what you think it is insights from phytolith carbon research abstract for proper interpretation of radiocarbon 14c age results the carbon fraction being dated must be identified beforehand ideally as a single homogeneous entity that best represents the event being studied radiocarbon dating of fossil phytoliths biosilica formed in living higher plants has been used in a number of archaeology and paleoenvironmental studies more precisely the carbon occlusion phytc has been 14c dated this method relies on the phytc being photosynthetic in origin so that its 14c signature is similar to that of the host plant however we have recently presented overwhelming evidence that phytc in modern plants is made up of a mixture of carbon photosynthesized by the plant from atmospheric co2 and soil carbon comprised of multiple 14c signatures ages the discussion presented here is based on our assessments of phytc 14c signatures their chemical nature location origin and fate as well as the current state of knowledge on plant cell silica interactions with biomolecules finally regardless of the fact that there are cases where fossil phytc 14c results appear to match expected values the impossibility of establishing a priori either the amount of the soil carbon contribution to phytc or the mean 14c age of its occluded mixed pool precludes the use of phytoliths as a reliable 14c dating tool

pleistocene rhine thames landscapes geological background for hominin occupation of the southern north sea region this paper links research questions in quaternary geology with those in palaeolithic archaeology a detailed geological reconstruction of the netherlands south west offshore area provides a stratigraphical context for archaeological and palaeontological finds progressive environmental developments have left a strong imprint on the area s palaeolithic record we highlight aspects of landscape evolution and related taphonomical changes visualized in maps for critical periods of the pleistocene in the wider southern north sea region the middle pleistocene record is divided into two palaeogeographical stages the pre anglian elsterian stage during which a wide land bridge existed between england and belgium even during marine highstands and the anglian elsterian to saalian interglacial with a narrower land bridge lowered by proglacial erosion but not yet fully eroded the late pleistocene landscape was very different with the land bridge fully dissected by an axial rhine thames valley eroded deep enough to fully connect the english channel and the north sea during periods of highstand this tripartite staging implies great differences in i possible migration routes of herds of herbivores as well as hominins preying upon them ii the erosion base of axial and tributary rivers causing an increase in the availability of flint raw materials and iii conditions for loess accumulation in northern france and belgium and the resulting preservation of middle palaeolithic sites 2011 john wiley sons ltd

plant impact on the biogeochemical cycle of silicon and related weathering processes abstract the contribution of plants to the biogeochemical cycle of si and related weathering processes was studied in an equatorial rainforest ecosystem congo where the biologic turnover of si is high 58 to 76 kg ha y litterfall leaves a soil profile and groundwaters were analysed phytoliths and organic matter have a similar distribution with depth in the soil profile the model of a bicompartmental distribution of organic matter is applied to phytolith distribution and shows that about 92 of the biogenic silica input is rapidly recycled while about 8 of the biogenic silica input supplies a stable pool of phytoliths with a lower turnover reprecipitation of silica was observed at the base of the soil profile indicating a local geochemical environment that is oversaturated with respect to amorphous silica a balance in biogeochemical cycle of si requires that the vegetation absorb dissolved silicon released from weathering of minerals which otherwise would be available for mineral neoformation or export from the profile towards regional drainages plant uptake of si increases the chemical weathering rate without increasing the denudation rate this study shows that the uptake storage and release of si by the vegetation have to be taken into account when using dissolved si for tracing chemical weathering dynamics

a complete terrestrial radiocarbon record for 11 2 to 52 8 kyr b p radiocarbon 14c provides a way to date material that contains carbon with an age up to 50 000 years and is also an important tracer of the global carbon cycle however the lack of a comprehensive record reflecting atmospheric 14c prior to 12 5 thousand years before the present kyr b p has limited the application of radiocarbon dating of samples from the last glacial period here we report 14c results from lake suigetsu japan 35 35 n 135 53 e which provide a comprehensive record of terrestrial radiocarbon to the present limit of the 14c method the time scale we present in this work allows direct comparison of lake suigetsu paleoclimatic data with other terrestrial climatic records and gives information on the connection between global atmospheric and regional marine radiocarbon levels

taphonomical aspects of silica phytoliths in the loess sediments of the argentinean pampas abstract although pampean loess and pedostratigraphy processes in the pampas have been widely studied phytoliths observed in these sediments have been only mentioned without further quantitative or qualitative studies the present work is a first step towards an understanding of the environmental significance of loess phytolith datasets and their validity for palaeoenvironmental reconstructions and to comprehend the environmental conditions of loess formation the research focused on the taphonomy of loess phytoliths investigating the loess morphological and sedimentological characteristics variability in the qualitative and quantitative assemblage composition the phytolith frequency and were also phytolith extraction techniques the results highlight that the phytolith pool of loess deposits still retains information about the past vegetation and phytolith analysis from these deposits can be a useful exercise to further comprehend past climatic and environmental conditions under which loess palaeosol sequences formed

detection of burning of plant materials in the archaeological record by changes in the refractive indices of siliceous phytoliths abstract the most resilient remains of plants in most archaeological sites are the siliceous phytoliths special cells that are partially or completely silicified during the plant s life these cells have characteristic morphologies and thus the phytoliths can often be used to identify the taxonomic affinities of plants brought to an archaeological site in order to determine what they were used for other means of analysis are needed we present here a method to distinguish burnt from unburnt phytolith assemblages the method is based on measuring the refractive index ri of individual phytoliths the phytoliths even from a single plant have a range of ri values burning a phytolith sample causes a shift to higher ri comparing burnt and unburnt samples we demonstrate that it is possible to differentiate between them based on the fraction of phytoliths with ri higher than 1 440 this serves as a basis for a simplified mode of measurement that requires only the use of a petrographic light microscope and a mineral oil of ri 1 440 we apply the simplified method to two natufian samples from hayonim cave western galilee israel

aeolian fluvial interaction and climate change source bordering dune development over the past 100 ka on cooper creek central australia abstract this study provides an interpretation of interrelated quaternary fluvial and aeolian activity related to climate change on cooper creek in the lake eyre basin in southwestern queensland central australia the extensive muddy floodplain is characterised by buried sandy palaeochannels now almost entirely invisible but stratigraphically connected to source bordering dunes that emerge as distinctive sandy islands through the floodplain surface luminescence dating has identified pronounced periods of fluvial activity represented by abundant sandy alluvium from marine isotope stages mis 8 3 while all these sandy fluvial episodes on cooper creek were much more powerful than anything subsequent they appear to be ranked in order of declining activity mis 8 6 saw reworking of almost the entire floodplain whereas subsequent phases of reworking were far less extensive source bordering dunes were derived from active sandy channels in late mis 5 85 80 ka and mid mis 3 50 40 ka after 40 ka sand channel activity largely ceased and the floodplains and channels were inundated with mud isolating the dunes as emergent features although aeolian reworking of the upper parts of some dunes has continued to the present they show remarkable resilience having survived without appreciable migration for at least 40 ka whilst the channels once determined the location of source bordering dunes in an interesting role reversal the remnant dunes now determine the position of many contemporary flood channels and waterholes by deflection and confinement of overbank flows

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

geomorphic and sedimentary response of rivers to tectonic deformation a brief review and critique of a tool for recognizing subtle epeirogenic deformation in modern and ancient settings abstract rivers are extremely sensitive to subtle changes in their grade caused by tectonic tilting as such recognition of tectonic tilting effects on rivers and their resultant sediments can be a useful tool for identifying the often cryptic warping associated with incipient and smaller scale epeirogenic deformation in both modern and ancient settings tectonic warping may result in either longitudinal parallel to floodplain orientation or lateral normal to floodplain orientation tilting of alluvial river profiles alluvial rivers may respond to deformation of longitudinal profile by 1 deflection around zones of uplift and into zones of subsidence 2 aggradation in backtilted and degradation in foretilted reaches 3 compensation of slope alteration by shifts in channel pattern 4 increase in frequency of overbank flooding for foretilted and decrease for backtilted reaches and 5 increased bedload grain size in foretilted reaches and decreased bedload grain size in backtilted reaches lateral tilting causes down tilt avulsion of streams where tilt rates are high and steady down tilt migration combing where tilt rates are lower each of the above effects may have profound impacts on lithofacies geometry and distribution that may potentially be preserved in the rock record fluvial sedimentary evidence for past tilting is traditionally based on the assumption that depositional features reminiscent of modern fluvial tectonic effects are evidence for past tectonic effects where it is closely associated with historically active structures or where non tectonic causes cannot be invoked however caution must be exercised when using these effects as criteria for past or current tectonic warping as these effects may be caused by non tectonic factors these non tectonic causes must be eliminated before tectonic interpretations are made

quantitative resolution of the debate over antiquity of the central australian landscape implications for the tectonic and geomorphic stability of cratonic interiors we report the first measure of long 100 myr and short 1 myr term denudation rates from key geologically stable landforms in the davenport range central australia these landforms have previously been assigned a cambrian age which arguably places them amongst the oldest persistent landforms on the continent if not on earth our results from combined apatite fission track thermochronology and in situ cosmogenic radionuclide analyses using 10 be and 26 al show that while average exhumation rates are low the denudation history for this cratonic region is incompatible with extreme sub aerial longevity and long term tectonic and geomorphic stability our revised model for the landscape evolution of this region is consistent with one of maximum burial prior to and during the mesozoic followed by a phase of kilometre scale exhumation that was largely complete by the beginning of the cainozoic we suggest that a similar process of burial and exhumation has probably been responsible for the sub aerial preservation of seemingly ancient landforms elsewhere in australia

management of residues and natural resources at san cristobal rock shelter contribution to the characterisation of chalcolithic agropastoral groups in the iberian peninsula abstract use of the space and settlement patterns at the deposit of san cristobal are characterised anthropogenic activities at the site are revealed through an interdisciplinar approach based on microstratigraphic and palaeobotanical studies correlation of micromorphological silica phytolith charcoal pollen and non pollen palynomorph analyses and calcitic pseudomorph and faecal spherulite quantification are coupled with excavation data and macroscopic observations results provide insights into livestock keeping practices at the rock shelter animal feeding strategies management of residues and occupation mode of the site they also contribute to reconstruct the formation processes of the deposits and to outline the ecological frame of the site during its use as herding facility over the chalcolithic the immediate chrono cultural context of the investigated sequence is outlined allowing discussion on the possible role of the activities at the rock shelter in the territorial organisation of local early agropastoral groups at the time of megalithism development from a methodological point of view this work shows that high resolution sedimentary contextualisation of archaeological remains is essential to build up more accurate and reliable interpretations on livestock management and the use of natural resources in prehistoric deposits it also highlights the contribution of excavation strategies adapted to the particularities of pen deposits to better understand the archaeological evidence of early pastoral practices in cave and rock shelters during fieldwork