u series dating of fossil teeth and carbonates from snake cave thailand abstract snake cave thailand is an important site for the study of the evolution in southeast asia leading to a discovery of rich and various faunas including a human tooth fossils of large and small mammals converge to indicate on the basis of faunal assemblage a late middle pleistocene age for the fossiliferous layers on the other hand previous u series dating of carbonates furnished a lower limit for the fossils of about 130 ky in order to achieve a better comprehension of the chronology of the cave the uranium series method for absolute age determination has been applied to some carbonates older than those studied previously and to fossils themselves we used the isochron technique approach to yield valuable ages because spleleothem samples consist in a mixture of calcite and detrital contamination the results obtained suggest that the main fossiliferous level is older than about 160 ky the application of the u series method to tooth samples from this tropical cave leads to erroneous ages probably because of post depositional groundwater movements

the rock physics and geochemistry of carbonates exposed to reactive brines when carbonate rich rocks are brought into contact with an acidic brine their mechanical and acoustic responses depend on many factors including ph porosity permeability effective stress and time these complexities hinder the understanding of processes such as hydrothermal fluid circulation seismicity and deep burial diagenesis the present study addresses how different lithofacies exposed to the same reactive brine undergo varying degrees of transformation and whether it is possible to remotely detect these phenomena in the earth results are presented from fluid injections carried out on a large and varied set of calcareous rocks under hydrostatic stress the output brine was analyzed for dissolved mineral concentrations and the rock porosity permeability axial strain ultrasonic velocity and images from electron microscopy were contrasted before and after injection microbialites were found to be the lithofacies most vulnerable to changes in their transport properties however all samples irreversibly compacted with the greatest strain in the most porous and permeable cores the most extreme structural changes discovered through imaging were the welding of microporous zones grain sliding and the fracturing of various phases observations are consistent with a chemically enhanced weakening of the rock frame that generated compliant pores the associated decrease in velocity of the dry rock can be approximated with linear relations that depend on both porosity and effective stress

intertropical latitudes and precessional and half precessional cycles a mcintyre and b molfino in their report about the forcing of atlantic equatorial and subpolar millennial cycles by precession suggest that climatic changes in high polar latitudes which are related to heinrich iceberg surges may be caused by events that occur in low latitudes 1 1 this

mechano chemical interactions in sedimentary rocks in the context of co2 storage weak acid weak effects abstract due to the corrosive nature of dissolved co2 the potential short or long term alteration of rock properties represents a major issue in several sites where natural co2 circulation is observed as well as in reservoirs targeted for storage of anthropogenic co2 to date this has been primarily studied from a transport chemical perspective with laboratory evidence of microstructural modifications together with the consequences for flow properties compared to the transport chemical aspects the mechanical chemical aspects have been less investigated though it is to be expected that mechanical properties e g elastic properties failure parameters and time dependent mechanical behaviour could potentially be affected in a similar manner to hydraulic parameters yet since co2 is a weak acid the ph drop is expected to be moderate with a likely lower limit close to 4 0 the buffering of ph by calcite minerals present in most reservoirs targeted for storage may further limit the ph drop as well as confining it to a localized rock volume around the injection well this leads to the question of the magnitude and time spatial scales of chemically mediated mechanical processes during co2 sequestration the authors propose to address this issue by reviewing recent laboratory based studies restricted to sedimentary rocks namely reservoir rocks carbonate or sandstone intact or fractured caprocks and fault rocks key findings include the following 1 the short term impact on the elastic and inelastic behaviour of intact caprocks remains limited 2 shear strength weakening is likely to be respectively low and low to moderate for shale clay rich and anhydrite rich faults but without modifying slip stability in either case 3 the largest impact is located within carbonate reservoirs but with a broad range of reported responses depending on hydrodynamic conditions closed or open and on dissolution regime uniform or channelling and 4 creep experiments confirm that co2 induced dissolution may enhance long term compaction of carbonate reservoirs but the magnitude of acceleration varying from non significant to 50 times depends to a large extent on site specific conditions grain size ph temperature effective stress state etc which renders any direct extrapolation from laboratory to reservoir scale difficult finally some directions for future research studies are discussed

land sea correlation by means of terrestrial and marine palynomorphs from the equatorial east atlantic phasing of se trade winds and the oceanic productivity abstract sporomorphs and dinoflagellate cysts from site gik16867 in the northern angola basin record the vegetation history of the west african forest during the last 700 ka in relation to changes in salinity and productivity of the eastern gulf of guinea during most cool and cold periods the afromontane forest rather than the open grass rich dry forest expanded to lower altitudes partly replacing the lowland rain forest of the borderlands east of the gulf of guinea except in stage 3 when oceanic productivity was high during a period of decreased atmospheric circulation high oceanic productivity is correlated to strong winds the response of marine productivity in the course of a climatic cycle however is earlier than that of wind vigour and makes wind stress induced oceanic upwelling in the area less likely monsoon variation is well illustrated by the pollen record of increased lowland rain forest that is paired to the dinoflagellate cyst record of decreased salinity forced by increased precipitation and run off

late pleistocene mammalian assemblages of southeast asia new dating mortality profiles and evolution of the predator prey relationships in an environmental context karstic sites have great potential for yielding data regarding changes in faunal communities in the pleistocene of southeast asia in this region the majority of fossil bearing deposits are karstic breccias which generally demonstrate a complicated sedimentary history while most of the mammalian assemblages recovered in these deposits are only composed of isolated teeth their study remains essential for reconstructing paleoecology and paleoclimatology of the region we analyzed the assemblages recovered in three mainland and two insular karstic sites tam hang south and nam lot in northern laos duoi u oi in northern vietnam punung in central java and sibrambang in western sumatra and obtained new chronologies for three of these sites so that their significance could be discussed within their correct chronological context the resulting age ranges place the sites in mis5 and mis4 the comparative analysis of the faunas in terms of taphonomy taxonomic diversity and abundance and mortality profiles cervus unicolor sus scrofa sus vittatus rhinocerotids and tapirus indicus reveals marked differences in prey predators carnivores and or humans relationships in relation to habitat the study of hominines bearing sites punung nam lot duoi u oi allows us to emphasize different interactions with large carnivores felids hyaenids canids

time lapse acoustic transport and nmr measurements to characterize microstructural changes of carbonate rocks during injection of co2 rich water abstractwe investigated how changes induced in the microstructure of carbonate rocks by the injection of co2 rich water affect pore network properties in particular we investigated from multiple perspectives the microstructural changes and types of porosity that alter the observable geophysical properties we thereby refined our understanding of induced modification of the pore network our experimental protocol included a suite of time lapse acoustic transport and nuclear magnetic resonance nmr measurements along with scanning electron microscopy sem and ct scan images these gave us complementary sensitivity to changes in different properties of the pore space induced porosity variations were smaller than in previous reported results because of chemomechanical compaction resulting from dissolution under pressure no porosity enhancements larger than 0 8 pu were observed results indicated that dissolution occured primarily in the grain coating cement and the microporosity of the micritic phase

qualitative landslide susceptibility assessment by multicriteria analysis a case study from san antonio del sur guantanamo cuba geomorphological information can be combined with decision support tools to assess landslide hazard and risk a heuristic model was applied to a rural municipality in eastern cuba the study is based on a terrain mapping units tmu map generated at 1 50 000 scale by interpretation of aerial photos satellite images and field data information describing 603 terrain units was collected in a database landslide areas were mapped in detail to classify the different failure types and parts three major landslide regions are recognized in the study area coastal hills with rockfalls shallow debris flows and old rotational rockslides denudational slopes in limestone with very large deep seated rockslides related to tectonic activity and the sierra de caujeri scarp with large rockslides the caujeri scarp presents the highest hazard with recent landslides and various signs of active processes the different landforms and the causative factors for landslides were analyzed and used to develop the heuristic model the model is based on weights assigned by expert judgment and organized in a number of components such as slope angle internal relief slope shape geological formation active faults distance to drainage distance to springs geomorphological subunits and existing landslide zones from these variables a hierarchical heuristic model was applied in which three levels of weights were designed for classes variables and criteria the model combines all weights into a single hazard value for each pixel of the landslide hazard map the hazard map was then divided by two scales one with three classes for disaster managers and one with 10 detailed hazard classes for technical staff the range of weight values and the number of existing landslides is registered for each class the resulting increasing landslide density with higher hazard classes indicates that the output map is reliable the landslide hazard map was used in combination with existing information on buildings and infrastructure to prepare a qualitative risk map the complete lack of historical landslide information and geotechnical data precludes the development of quantitative deterministic or probabilistic models

controls on sonic velocity in carbonates compressional and shear wave velocities v p and v s of 210 minicores of carbonates from different areas and ages were measured under variable confining and pore fluid pressures the lithologies of the samples range from unconsolidated carbonate mud to completely lithified limestones the velocity measurements enable us to relate velocity variations in carbonates to factors such as mineralogy porosity pore types and density and to quantify the velocity effects of compaction and other diagenetic alterations

the environmental effects of the uplift of the qinghai xizang plateau the intense upheaval of the qinghai xizang plateau took place 2 ma bp the terraces of the yellow river in the lanzhou region and its upper sections provide a record of the uplift of the plateau the interaction of glaciation cycles resulting from climatic changes and pulsating tectonic upheavals are both involved in the record of environmental change across the plateau three tectonic climatic events which are termed respectively the qinghai xizang movement the huanghe yellow river movement and the gonghe movement occurred 2 1 5 1 0 and 0 15 ma bp the upheaval of the qinghai xizang plateau was the trigger mechanism of the asian monsoon the loess plateau was formed in the monsoon triangle of east asia human origins and human evolution may have been stimulated by the uplift of the qinghai xizang plateau

response of western pacific marginal seas to glacial cycles paleoceanographic and sedimentological features abstract this paper reviews the recent progress in late quaternary studies in five northwestern pacific marginal seas especially the south china sea as an example a series of marginal seas separate asia from the pacific ocean and significantly modify the material and energy flux linkage between land and sea during glacial cycles the sea level induced environmental signal was amplified in the marginal seas giving rise to drastic changes in areas and configurations of these seas and to reorganization of sea water circulation in basins since most of the western pacific marginal seas are influenced by monsoon circulation and some of these are located within the western pacific warm pool the glacial geographic changes have produced a profound impact on regional and global climate for example the decrease of sea area and sea surface temperature sst in the marginal seas was one of the factors responsible for the enhanced aridity of inland china during the glaciation glacial intensification of the winter monsoon and increased seasonality of sst in marginal seas might explain at least partly the apparent discrepancy between the tropical paleotemperature estimations based on terrestrial and open ocean records in this region as the western pacific marginal seas trap terrigenous material supplied by east asia the deep water sedimentation rates there can be one to two orders of magnitude higher than in the open ocean down slope sediment transport is more active when the sea level changes particularly during the deglaciation at least four types of carbonate cycles have been recognized in the western pacific marginal seas and each of those contains environmental signals from the surface and deep sea water as well as from the drainage basin

alluvial terrace systems in zhangjiajie of northwest hunan china implications for climatic change tectonic uplift and geomorphic evolution abstract this paper reports the latest details from two comprehensive investigations of alluvial terrace sequences in zhangjiajie northwest hunan province china seven alluvial terrace units along the maoxi river and four terrace sequences along the suoxi river record significant regional geomorphic history rates of regional quaternary uplift and climate change are reconstructed using topographic and stratigraphic evidence from terrace and adjacent cave deposits along with electron spin resonance esr and thermo luminescence tl dating controls between 928 ka and 689 ka the time averaged uplift rate or incision rate was 0 16 m ka the rate decreased to 0 05 m ka between 689 ka and 347 ka and then increased slightly to 0 11 0 14 m ka after 347 ka the inferred incision rate increased roughly from 0 21 0 32 m ka to 0 51 m ka from the late pleistocene to present the seven alluvial phases t7 t1 and their associated chronology are consistent with climatic variations at regional and or global scales suggesting that these terraces represent climate driven pauses imprinted atop the record of long term tectonically induced incision by rivers insights from these alluvial terrace staircases and cave features indicate that the spectacular sandstone peak forest landscape of the study area has emerged since the middle period of the middle pleistocene

nam lot mis 5 and duoi u oi mis 4 southeast asian sites revisited zooarchaeological and isotopic evidences abstract the nam lot site in laos and the hominin bearing duoi u oi site in vietnam are dated to mis 5 86 72 ka and mis 4 70 60 ka respectively located in the same latitudinal belt 20 n in the north of the indochinese area the faunal assemblages recovered from breccia deposits in a karstic context have the potential to provide information on the palaeoenvironmental conditions faced by earliest modern humans when they entered the southeast asian mainland here zooarchaeological evidence of faunas are reviewed combined with a new stable isotope analysis 13c and 18o of tooth enamel of mammals from nam lot 86 72 ka to explore environmental conditions during mis 5 4 periods in both sites large predators hyena tiger leopard and dhole had access to a great diversity of prey among mammals the nam lot isotopic results indicate during mis 5 a complexity in the forest habitats with closed low light tropical rainforest intermediate rainforest and c3 c4 open woodland savanna this woodland ecosystem notably the intermediate rainforest carried most of the ungulate biomass with a variety of small to large bodied ground dwelling animals

the middle pleistocene mammalian fauna from tam hang karstic deposit northern laos new data and evolutionary hypothesis new fossil material was recovered at tam hang during the second fieldwork season conducted in 2007 by a lao french american team the tam hang site is located in northern laos in the hua pan province about 260 km from vientiane the breccias of the tam hang south locality produced 404 new fossil specimens which complete the previous material recovered in 2003 the fossiliferous deposits are described geologically in terms of palaeontology the mammalian fauna is essentially composed of isolated teeth of middle to large sized mammals artiodactyla perissodactyla proboscidea carnivora rodentia primates the overall fauna is compared to the six well documented middle to late pleistocene faunas from the indochinese province yenchingkuo phnom loang thum wiman nakin lang trang duoi u oi ma u oi on the basis of the faunal composition and evolutionary stages of the species a biochronological framework at the transition between the middle pleistocene and the late pleistocene is proposed

holocene variations in asian monsoon moisture a bidecadal sediment record from the south china sea the east asian monsoon system involves extensive transport of sensible latent heat between land and sea and from low to high latitudes our high resolution bidecadal marine records present a first detailed history of monsoon climate change over the holocene the high amplitude perturbation in monsoon moisture centered at 8 150 years ago and the monsoon maximum in the early holocene show inter hemispheric teleconnections to both a cool episode in greenland and to the indian monsoon monitored in the arabian sea periodicities of 84 102 and especially near 775 years in monsoon variation suggest a climatic forcing both by long term oscillations in thermohaline circulation and possibly solar activity cycles

a pollen record of the last 37 ka in deep sea core 17940 from the northern slope of the south china sea this paper presents the palynological record of deep sea core 17940 from the south china sea 20 07 n 117 23 e water depth 1727 m this core is about 13 30 m long and covers the last 37 ka a total of 103 samples were counted at 10 cm intervals with a time resolution of ca 360 yr three pollen zones are recognized zone p1 14c age ca 37 0 15 0 ka b p 13 06 8 70 m is characterized by the expansion of montane conifers tsuga picea and abies and colonization by temperate grassland mainly artemisia on the exposed northern continental shelf as well as by frequent natural fires indicated by high values of charcoal concentrations this implies that the climate of this period was cool and dry frequent alternations of montane conifers and grassland dominated by artemisia indicate that oscillations of comparatively cool and humid conditions with temperate and dry conditions occurred according to the oxygen isotope data the period corresponds to stage 3 and the last glacial maximum climatic warming p2 a 8 70 7 23 m 15 0 11 3 ka b p associated with a rapid rise in sea level from ca 14 ka b p is inferred by expansion of tropical subtropical broad leaved forest with a replacement of grassland by mangroves mainly rhizophora and sonneratia this time interval may be assigned to the bolling allerod warming stage subsequently climatic cooling reflected by expansion of both montane conifers and upper montane rain forests mainly podocarpus and dacrydium during the period of ca 11 3 10 0 ka b p p2 b 7 23 6 6 m may be correlated with the younger dryas cold spell the similarity of pollen assemblages during the holocene and in the surface sediment from the northern south china sea implies that the vegetation and climate during the last 10 000 years was close to those of the present during the last 1400 years human activities are reflected in the sharp increase of dicranopteris fern spores

rock physics analysis and time lapse rock imaging of geochemical effects due to the injection of co2 into reservoir rocks the fundamental concept of time lapse seismic monitoring is that changes in physical parameters such as saturation pore fluid pressure temperature and stress affect rock and fluid properties which in turn alter the seismic velocity and density increasingly however time lapse seismic monitoring is called upon to quantify subsurface changes due in part to chemical reactions between injected fluids and the host rocks this study springs from a series of laboratory experiments and high resolution images assessing the changes in microstructure transport and seismic properties of fluid saturated sandstones and carbonates injected with co2 results show that injecting co2 into a brine rock system induces chemo mechanical mechanisms that permanently change the rock frame injecting co2 into brine saturated sandstones induces salt precipitation primarily at grain contacts and within small pore throats in rocks with porosity lower than 10 salt precipitation reduces permeability and increases p and s wa

the effect of micrite content on the acoustic velocity of carbonate rocks abstractwe have demonstrated the effect of micrite content on the acoustic properties of well controlled microstructures that are created in the laboratory to closely mimic those of carbonate rocks in particular we examined the effect of micrite content on the acoustic velocity sensitivity of velocity to pressure and changes in velocity resulting from dissolution upon saturation with a reactive fluid we followed dunham s classification and fabricated the samples by mixing coarse sand sized and very fine micrite sized calcite grains in different ratios and then cold compressing the mixture the acoustic velocities were measured under benchtop conditions and as functions of confining pressure before and after the injection of a co2 aqueous solution the benchtop measurements indicated that the addition of micrite made the frame of the carbonate samples stiffer because the sensitivity of velocity to pressure decreases as the content of micrite increases we hypothesized a stiffer pore structure in

palynology of eastern indonesian marine piston cores a late quaternary vegetational and climatic record for australasia abstract pollen analyses of late quaternary sediments from nine marine piston cores reveal a continuous vegetation and environmental record for eastern indonesia and northern australia on the island of halmahera a montane oak forest largely replaced the tropical lowland vegetation during the last glacial period while fern cover was strongly reduced during its maximum 18 000 yr b p climate was cooler and slightly drier than today around 10 000 yr b p mangrove vegetation expanded following the rising sea level in our western new guinea record at 14 000 yr b p climate grew warmer and slightly wetter until it stabilised around 10 000 yr b p at that time the mid to upper montane forests expanded to their full altitudinal range and fern cover increased while montane oak forest grassland and woodland areas had contracted in our marine pollen records during the last glacial the climate of northern australia was distinctly drier than today grassland vegetation with sedges increased considerably at 38 000 and 24 000 yr b p replacing eucalypt forest and culminating in a maximum grassland cover at the height of the last glaciation 18 000 yr b p the rapid sea level rise allowed the expansion of mangrove forests and salt bush marshes which had become established on the large tidal flats of the drowning sahul shelf around 12 000 yr b p one piston core g6 4 extends to 300 000 yr b p and shows that glacial periods are characterized by high pollen concentrations in marine sediments recording expanding grassland vegetation during interglacial woodland and fern cover increased while pollen concentrations in the sediments were low after 190 000 yr b p a more open vegetation suggests that conditions were in general much more arid than before repeated mangrove vegetation expansions suggest major rises in sea level at around 244 000 220 000 and 130 000 yr b p

recent advances in time lapse laboratory rock physics for the characterization and monitoring of fluid rock interactions abstractmonitoring thermo chemo mechanical processes geophysically e g fluid disposal or storage thermal and chemical stimulation of reservoirs or natural fluids simply entering a new system raises numerous concerns because of the likelihood of fluid rock chemical interactions and our limited ability to decipher the geophysical signature of coupled processes one of the missing links is understanding the evolution of seismic properties together with reactive transport because rock properties evolve as a result of chemical reactions and vice versa capturing this coupling experimentally is one of the missing elements in the existing literature this paper describes recent advances in rock physics experiments to understand the effects of dissolution induced compaction on acoustic velocity porosity and permeability this paper has a dual aim understanding the mechanisms underlying permanent modifications to the rock microstructure and providing a richer set of experimental information to inform th

impact of chemical alteration on the poromechanical properties of carbonate rocks the technical and economic success of a co2 geological storage project requires the preservation of the site injectivity and integrity properties over its lifetime unlike conventional hydrocarbon gas injection co2 injection may imply geochemical reactions between acidified pore fluids and target reservoir formations leading to modifications of their poromechanical properties to date the chemical effects on the host rock mechanical behaviour are not satisfactorily taken into account in sitescale numerical models of co2 injection mainly due to a lack of quantitative data the present experimental work aims at characterizing the evolution of carbonate poromechanical properties induced by acid alteration unlike standard experimental approaches the implemented alteration method induces a homogeneous dissolution pattern which ensures reliable poromechanical measurements on altered samples these well controlled alteration conditions allow a proper interpretation of the test results through the macroscopic continuous approach of poromechanics petrophysical geomechanical and petroacoustic properties of outcrop carbonate samples have been measured for different levels of alteration to mimic long term exposure to reactive brine the obtained experimental data show clear trends of chemically induced mechanical weakening nuclear magnetic resonance measurements and microscanner imaging performed before and after alteration have provided complementary insights into the alteration effects at the microscopic scale

geochronology of ailuropoda stegodon fauna and gigantopithecus in guangxi province southern china abstract pleistocene faunas from south china are difficult to subdivide based on the long temporal ranges of many taxa and a reduced number of genera in comparison to faunas from temperate north china in south china the ailuropoda stegodon fauna is a very general one and includes a relatively stable suite of genera that apparently persisted for long periods of time these attributes have made constraining its time range difficult application of electron spin resonance esr dating of tooth enamel constrains the ages well where uranium uptake was minor where uranium uptake into teeth was significant an approach combining esr and 230th 234u isotopic analysis also yields excellent ages previous estimates of early middle and late pleistocene time ranges previously determined by biostratigraphic seriation for the ailuropoda stegodon fauna are confirmed in all cases but are made more precise with our approach including specific time ranges for certain archaic taxa absolute dating also yields an extended time range for gigantopithecus blacki of 1200 to 310 ka

quaternary forest and climate history of hokkaido japan from marine sediments abstract pollen data from quaternary marine sediments deposited in central hokkaido northern japan provide insight into northeast asian vegetation and climatic changes over the last few million years during the early pleistocene coniferous forest dominated by picea and cryptomeria japonica and taiga composed of larix and picea developed under cool wet and cold dry climates respectively strong climatic contrasts are inferred from late pleistocene interglacial and glacial pollen assemblages which precede the last glacial cycle in the former cool temperate broad leaf forest mainly composed of fagus reflects a warmer and wetter climate than now in the latter taiga similar to that now found in northern sakhalin apparently flourished in hokkaido the composition of pollen assemblages correlated with oxygen isotope stage 5 changed from cool temperate forest of quercus ulmus and juglans substage 5e to picea larix taiga substage 5d cool temperate forest of quercus and ulmus substage 5c and picea abies forest substage 5b compared with present conditions climate during stage 5 in northern japan apparently fluctuated from warmer wetter to colder drier taiga composed of picea pinus and larix indicating colder dry conditions during stage 4 was replaced by picea abies forest and picea larix taiga in stage 3 suggesting relatively cool and cold dry environments taiga and mixed forest with taiga and cool temperate components characterize stage 2 holocene forests with juglans betula and quercus juglans were succeeded by picea and abies during the early holocene warm interval 7000 bp subsequently quercus ulmus and abies alnus assemblages reflect climatic deterioration pan mixed forest has been developed in hokkaido since 2000 bp

a direct link between the china loess and marine δ 18 o records aeolian flux to the north pacific most studies of quaternary climates conducted during the past 150 years have focused on glacial sequences and for the past 25 years marine sediments have provided significant further understanding of glacial and interglacial palaeoclimates an important goal of palaeoclimatology however to link the well known detailed continental records to marine records of similar resolution has yet to be realized the classic loess sequences of china provide an apparently continuous record of continental climate over the past 2 4 million years1 2 the oxygen isotope 18o timescale developed from the marine record3 gives us a global chrono stratigraphy of late pleistocene climates previously it has been suggested in studies of the aeolian component in pelagic sediments that it may be possible to link these two records directly by finding a suitable core from the north west pacific downwind from china4 5 here we report the results of such an effort for core v21 146 fig 1 and tie the last 500 000 years of the chinese loess soil sequence directly to the 18o timescale and in so doing refine the dating of regional loess and soil horizons

a record of fire vegetation and climate through the last three glacial cycles from lombok ridge core g6 4 eastern indian ocean indonesia abstract charcoal elemental carbon and clastic particle analyses have been undertaken on tropical marine core g6 4 collected from the eastern indian ocean between the lesser sunda islands of indonesia and northwestern australia to help interpret an existing pollen record in addition a new oxygen isotope record has been constructed and several radiocarbon dates produced to allow a refinement of the chronology of the core the record covers the last 300 000 years with three clear glacial interglacial cycles however the new oxygen isotope record and radiocarbon dates suggest a hiatus and it appears that most isotope stage 3 is missing interglacials are characterised by higher values of mangrove fern and rainforest pollen indicating wetter conditions than intervening glacials which have higher cyperaceae and chenopodiaceae values gramineae percentages are also generally higher during glacials but there is a sustained increase in grasses relative to eucalyptus about 185 000 years ago originally interpreted as a change to drier conditions an increase in burning from about 200 000 years ago from charcoal evidence suggests that fire may have been an important contributing factor this and subsequent increases in charcoal may reflect anthropogenic burning and are considered in relation to archaeological evidence for possible times of arrival of people within australia the elemental carbon record shows major differences to that from charcoal and further research is needed to interpret its meaning little consistent evidence for changes in climate or vegetation disturbance is provided by clastic particle influx which may well reveal a record of volcanicity within the region

late quaternary upwelling intensity and east asian monsoon forcing in the south china sea foraminifera from two cores off eastern vietnam and the northwestern philippines where modern summer and winter monsoon driven upwelling occurs in the south china sea respectively were analyzed to evaluate the changes in paleoproductivity and upper water structure over the last 220 000 yr we observed enhanced organic carbon flux and a shoaled thermocline when upwelling intensified off eastern vietnam during interglacial ages and off the northwestern philippines during glacial ages this indicates that the east asian summer monsoon increased while the winter monsoon decreased during interglacial ages particularly the upwelling reached a maximum off eastern vietnam during late marine isotopic stage mis 5 and off the northwestern philippines during mis 2 implying that the summer monsoon decreased gradually since mis 5 while the winter monsoon displayed an opposite trend the variations in upwelling proxies exhibit a distinct cyclicity with frequencies near 41 000 yr and 23 000 yr off eastern vietnam in contrast to a strong frequency peak near 100 000 yr off the northwestern philippines we suggest that the east asian summer monsoon has been forced by changes in solar insolation associated with precession and obliquity while ice volume forcing is probably a primary factor in determining the strength and timing of the east asian winter monsoon but with less important insolation forcing

laboratory measurements of the acoustic and transport properties of carbonate rocks and their link with the amount of microcrystalline matrix laboratory data and computer tomography ct scan image analysis of carbonate rocks were combined demonstrating a quantitative link between acoustic and transport properties the fraction of microcrystalline calcite micrite in the matrix and the grain to micrite matrix ratio samples from the monte acuto formation gargano italy a transgressive system tract tst whose microstructure ranges from basal pelagic mudstones to coarse calciturbidites were analyzed results indicate that high micrite rocks with low grain to micrite matrix ratios typical of low energy depositional settings are relatively stiffer and more impermeable in contrast lower amounts of micrite due to high energy depositional settings or its removal from intergranular macropores by progressive leaching of the matrix leads to high grain to micrite matrix ratios this process will increase porosity and reduce rock stiffness both of which reduce velocity decreasing micrite content correlates well with increasing macroporosity

the cave of the monk ban fa suai chiang dao wildlife sanctuary northern thailand biostratigraphic and paleoecological analyses of southeast asian pleistocene faunal sites are based on the assumption that paleontological assemblages are homogeneous this means that the sites formed during a time range shorter than biological evolution range and above all without faunal replacement induced by environmental successions detailed study of the cave of the monk paleontological site in thailand has lead to the conclusion that the complex pattern of this southeast asian paleontological site cannot support such an assumption the cave of the monk provides an ailuropoda stegodon assemblage typical of southeast asia pleistocene fauna the pluridisciplinary study presented here includes i site morphology description ii sedimentological analysis of fossiliferous deposits iii taphonomy study of the bone assemblage and iv electron spin resonance esr dating of tooth samples this integrated approach demonstrates the existence of a pleistocene porcupine den inhabited during mis 3 and 2 the features of this site are commonly reported for other paleontological sites of the area indicating that this kind of site formation is a very general one in southeast asia esr dating and porcupine ethological reports are used to question the site time averaging a time range of a few tens of thousands of years is suggested the paleoecological value of the site can then be discussed on one hand the assemblage is thought to be a valuable paleoenvironmental record considering that the bone accumulation agent is reputed to represent the fauna present in the environment without bias on the other hand the time averaging of the site indicates that site formation range likely covered the environmental fluctuations of the last climatic cycle this last hypothesis is confirmed by the alternating association of species indicated by the stratigraphic distribution of the faunal remains the research demonstrates the need for integrated and pluridisciplinary taphonomic study of southeast asian paleontological sites it also reveals the utility of a microstratigraphic analysis of a fossiliferous karst deposit in order to disentangle the succession of pleistocene mammals in response to environmental changes

pleistocene paleoceanography of the south china sea progress over the past 20 years article i nfo the south china sea scs has become one of the foci in paleoceanographic research and hydrocarbon explora tions over the last 20 years over the period at least 16 international cruises including odp ocean drilling pro gram leg 184 have investigated the scs and more than 2000 exploratory wells have been drilled the present paper attempts to synthesize progress in pleistocene paleoceanography because of the high depositional rates and favorable carbonate preservation the scs keeps valuable paleoceanographic archives for the low latitude pacific region which have helped to uncover potential ties between the low latitude oceanic biogeochemical evolution and step wise development of the boreal ice sheet it has been found that the 1 6 ma event marked a reorganization of the oceanic carbon reservoir associated with the restructuring of the southern and the tropical pacific ocean the mpt mid pleistocene transition and mbe mid brunhes event centered at 0 9 ma and 0 4 ma respectively were preluded by carbon isotope maxima 13 cmax iii and 13 cmax ii suggesting that major steps in the ice sheet development were preceded by significant changes in oceanic biogeochemistry the late pleistocene records have demonstrated the amplifying role of the scs in responding to glacial cycles as the amplitudes of sst and 18 ov ariations have been significantly amplified in the scs as compared with the open ocean at the same latitudes the amplification is ascribed to its semi enclosed morphology and the prevail ing monsoon climate the closure of the southern margin during glacial times led to stratification of the upper waters and specific faunal changes in the southern scs the seasonally reversing monsoon winds not only drive the surface circulation but also the biological production the n s gradient in oceanography and the sed iment transportdynamics such asthe asymmetric growth of the mekong river delta becauseof its distinguished position in the low latitudes between the largest continent and the largest ocean the scs provides important insight into the mechanism of environmental evolution with regards to ocean continent or high low latitude interactions

a dual aliquot regenerative dose protocol dap for thermoluminescence tl dating of quartz sediments using the light sensitive and isothermally stimulated red emissions abstract quartz sediments collected from a cave deposit in eastern indonesia display very weak optically stimulated luminescence osl ultraviolet emissions which we attribute to their volcanic provenance they do however emit at longer red wavelengths here we provide details of a new method of using a light sensitive red thermoluminescence tl signal to date the last time of exposure of quartz grains to natural sunlight which we have used previously to constrain the burial age of homo floresiensis remains found on the indonesian island of flores the samples examined typically contained a rapidly bleaching bleachable signal a slowly bleaching signal and a light insensitive heat reset signal we isolated the bleachable tl signal from the other unbleachable tl signals by means of a dual aliquot regenerative dose protocol dap and the bleachable dose was estimated by subtracting the unbleachable dose from the total dose taking into account the dose response differences between these signals the bleachable tl signal was found to be stable over geological timescales 17 5 million years to display minimal sensitivity change during successive cycles of dosing bleaching and heating and to exhibit reproducible dose response behaviour red tl measurements are commonly plagued by poor signal to noise ratios due to incandescence and possibly thermal quenching at high temperatures such difficulties have been minimised in this study by measuring the red tl isothermally at 260 c for an extended duration 1000 s red tl dating results are presented for eight samples of quartz from diverse sedimentary environments to illustrate the potential of this dating procedure in particular but not exclusively for quartz that has been heated in the past e g due to volcanic activity

engineering geological mapping developed in the fortaleza metropolitan region state of ceara brazil abstract engineering geological mapping was carried out at a scale of 1 100 000 in the fortaleza metropolitan region located in northeastern brazil to provide engineering geological information as an aid in planning land use and occupation in this study eight basic maps were produced drawing urban areas lithology unconsolidated materials in addition to geomorphological map showing slopes water resources engineering geological zoning and distribution of geological geotechnical environmental problems based on information collected through field and laboratory investigations the region was divided into nine engineering geological zones analyzed in terms of geohazard susceptibility and foundation excavation and waste disposal conditions

millennial reoccurrence of century scale abrupt events of east asian monsoon a possible heat conveyor for the global deglaciation high resolution sediment records from the south china sea reveal a winter monsoon dominated glacial regime and a summer monsoon dominated holocene regime during the last glacial cycle a fundamental change between regimes occurred during deglaciation through a series of millennial reoccurrences of century scale changes in the east asian monsoon eam climate these abrupt events centered at 17 0 15 9 15 5 14 7 13 5 13 9 13 3 12 1 11 5 and 10 7 14c ka correlate well with the millennial scale events in the santa barbara basin and the arabian sea i e a relationship between eam and el nino southern oscillation systems the abrupt increases in summer monsoon imply enhanced heat transport from low latitude sea area to the midlatitude high latitude land area the phase relationship between events of eam and ice sheet may reflect a faster eam response and a slower ice sheet response to the insolation change a far reaching conclusion is that the eam might have triggered the northern hemisphere deglaciation

geoarchaeological finds below liang bua flores indonesia a split level cave system for homo floresiensis we report on new geoarchaeological finds in a recently discovered cave chamber liang bawah cave under neath positioned below liang bua on the island of flores indonesia where the type specimen for homo floresiensis was recovered from late pleistocene sediment at the rear of liang bua a 23 m long shaft inclined at 60 leads to a lower chamber measuring 23 m x 24 m x 5 m high about half the size of liang bua stone artefacts and bones were found shallowly buried in rubble at the base of the shaft and around a 5 m high mud mound that fills the northwest sector of liang bawah we recovered 17 stone artefacts made from chert and volcanics and more than 220 well preserved bone elements belonging to endemic giant rats pigs primates small murid rodents bats and introduced species multi collector inductively coupled plasma mass spectrometer mc icpms analysis of uranium and thorium in carbonate coatings on four bones yielded ages of similar to 240 180 ka endemic giant rat femur similar to 110 60 ka unidentified phalanx similar to 33 23 ka pig skull fragment and similar to 7 3 ka giant rat femur which overlap with the similar to 95 to 17 ka occupation of liang bua by h floresiensis the similar to 33 23 ka age of the pig skull fragment indicates that sus sp may have dispersed into island southeast asia earlier than previously recognised the passageway at the rear of liang bawah and a currently buried front entrance represent two possible transport paths for cultural and faunal material to the cave chamber analysis of the geomorphic evolution of liang bawah shows that it may have been a late pleistocene depocentre for material transported from the occupation chamber of liang bua and a repository for human subsistence refuse or pit fall trap via the rear passage these physical attributes and the antiquity of the faunal remains found thus far indicate that liang bawah could contain an archive of the late pleistocene and potentially remains of h floresiensis c 2015 elsevier b v all rights reserved

long term event stratigraphy of the apulia platform margin upper jurassic to eocene gargano southern italy abstract the upper jurassic to eocene apulia platform margin and the eastward transition to the adjacent basinal deposits are well exposed in the gargano promontory southern italy a carbonate block that is part of the slightly deformed foreland of the southern apennine thrust belt the long term stratigraphy of this margin and slope transect is punctuated by five major dynamic phenomena that subdivide the succession into six second order sequences these events include 1 a valanginian drowning unconformity 2 an early aptian albian drowning and demise of the platform 3 late albian cenomanian platform margin failures 4 a santonian campanian retreat of the platform margin and 5 eocene uplift and platform margin collapse the first event is documented worldwide and is probably eustatic in origin the second is concomitant with some oceanic anoxic events oae the last three processes are probably related to foreland reaction to subduction and collision in the dinarides and hellenides thrust belts the ultimate cause of the albian cenomanian failures is more problematic a worldwide eustatic regression is documented at this time but regional geology seems to favor tectonic uplift

improving digital tools for quaternary field survey a case study of the rodoretto valley nw italy in the modern geological mapping activities geomatics technologies can facilitate data collection during field survey and avoid practical problems related to the transposition of that data onto topographic maps this paper describes an innovative tool the solid true orthophoto stop for the structured acquisition and recording of geological field survey data that is immediately available in a gis framework an experimental software graphical interface has been developed to manage the stop application during the survey the benefits of the stop system were tested by producing a digital map of the quaternary formations and landforms in a 3 km2 sector of the rodoretto valley a minor tributary of the germanasca valley northwestern italy

three large shifts in east asian monsoon circulation indicated by loess paleosol sequences in china and late cenozoic deposits in japan abstract correlations between loess paleosol sequences in china and late cenozoic deposits in japan suggest that the east asian monsoon circulation experienced three large shifts during the late cenozoic about 2 5 ma ago the onset of loess accumulation in north central china accompanied by a dramatic increase in eolian dust flux to the sea of japan marked a pronounced development of the east asian winter monsoon winds since ca 1 2 to 1 1 ma ago the obvious alternation of loess and paleosols in the chinese loess sequence with increased coarse grain size fraction in the loess units and higher than average magnetic susceptibility values in the paleosols and the repeated occurrence of interstratified marine clay layers in the osaka group of central japan indicate that the east asian monsoon circulation strengthened and the contrast between the summer and winter monsoons increased the paleosols of the chinese loess sequence were more strongly developed from ca 550 ka ago and loess started to accumulate in areas of the mid lower reaches of the yangtze river and in lake biwa of central japan from ca 450 ka ago reflecting more vigorous summer and winter monsoon circulations since ca 550 to 450 ka ago these large changes in east asian monsoon circulation were not only related to the changing solar radiation global glacial interglacial cycles and the changing configuration of land and sea but were also directly controlled by the uplift of the tibetan plateau

a 400 000 year record of vegetational and climatic changes from a volcanic basin leizhou peninsula southern china abstract the tianyang lake in leizhou peninsula is an enclosed crater formed during the early to middle pleistocene over 200 m of diatomaceous mud and clay were deposited in the last 400 000 years providing a continuous middle and late quaternary lacustrine sequence for paleoenvironmental studies the pollen record spans the last four glacial interglacial cycles equivalent to oxygen isotope stages ois 10 to 1 during most of the glacial phases fagaceous monsoon forest was replaced by altitudinal vegetation indicating a regional landscape transformation on the peninsula the montane forest reached down to the lowland by at least 600 m during the ois 6 and 8 in a cool and relatively wet condition with temperature estimated to be more than 4 c lower than present a further lowering of the montane forest belts by about 800 1000 m occurred in the ois 4 2 as implied by the appearance of many temperate elements during the last glacial maximum this mixed forest subsequently gave way to the poaceae grassland a savanna vegetation type favored by drier and cooler climatic conditions this drastic change implies a more significant drop in temperature and precipitation than the previous three glacial periods ois 10 8 and 6 it is thus inferred that the weakening of summer monsoon was more significant towards the end of the late pleistocene particularly during the last glacial maximum lgm

new palaeontological assemblage sedimentological and chronological data from the pleistocene ma u oi cave northern vietnam abstract this paper describes recent material gathered during the second fieldwork at ma u oi in november 2002 by a vietnamese french japanese team the ma u oi cave located in the province of hoa binh 60 km sw from hanoi northern vietnam belongs to a karstic network developed in triassic dark grey limestones the cave is filled with coarse grained breccias containing numerous fossil remains partially preserved at several loci inside the cave wall vault and ground we describe new teeth which confirm the occurrence of mammal taxa already mentioned at ma u oi bacon et al 2004 bacon a m demeter f schuster m long v t thuy n k antoine p o sen s nga h h huong n t m 2004 the pleistocene ma u oi cave northern vietnam palaeontology sedimentology and palaeoenvironments geobios 37 305 314 while others mainly microvertebrates emphasize the occurrence of new species for the pleistocene of vietnam we report here for the first time the occurrence of these microvertebrates of different groups primates rodents insectivores small reptiles and amphibians in the faunal assemblage among mammal taxa the presence of one more hominid affiliated to archaic homo is also attested by our findings u th dating carried out on 2 samples extracted from breccia speleothems confirms the biochronological estimate with fossiliferous fillings ranging from late middle pleistocene to late pleistocene

foraminiferal responses to major pleistocene paleoceanographic changes in the southern south china sea a detailed age model for core 17957 2 of the southern south china sea was developed based on delta 18 o coarse fraction magnetostratigraphy and biostratigraphy for the last 1500 kyr the delta 18 o record has clear similar to 100 kyr cycles after the mid pleistocene revolution mpr at the entrance of marine isotopic stage mis 22 planktonic foraminifera responded to the mpr immediately showing the increased sea surface temperature sst and dissolution after the mpr benthic foraminifera did not respond to it until the brunhes matuyama boundary since the mpr the depth of thermocline gradually became shallower until miss 6 5 this major change within miss 6 5 was also reflected in the decreased ssts and increased productivity and deep water mass thus two major pleistocene paleoceanographic changes were found one was around the mpr the other occurred within miss 6 5 which speculatively might be ascribed to the reorganization of surface and deep circulation possibly induced by tectonic forces

deep sea pollen from the south china sea pleistocene indicators of east asian monsoon abstract a high resolution pollen record sampling interval averages 820 years has been obtained from odp site 1144 water depth 2037 m northern south china sea the 504 m sequence in composition length covers the last 1 03 million years according to micropaleontological and isotopic stratigraphy the pollen assemblages are characterized by high proportions of pinus and herb pollen and by their frequent alternations based on these alternations 29 pollen zones have been recognized that are closely correlated to the marine oxygen isotope stages mis 1 29 pinus dominant pollen zones correspond to interglacial periods with lighter 18o values while herb marked ones relate to the heavier 18o stages assigned to glacials judging from the pollen data the exposed northern continental shelf of the south china sea during the glacials was covered by grassland and the extensive northern shelf has formed only since mis 6 ca 150 ka probably as a result of tectonic subsidence tree pollen influx values are indicative of winter monsoon which began to intensify 600 ka ago the summer monsoon variations can be approximated by the fern percentage within the total pollen and spore abundance and the result shows high values in general occurring at interglacials with the maxima at mis 15 5e and 1 the relatively high fern percentage with smaller amplitude in variations before 600 ka might suggest more stable humid conditions before the intensification of winter monsoon

the late quaternary palaeogeography of mammal evolution in the indonesian archipelago abstract the quaternary faunal evolution for the indonesian archipelago reflects the unique relationship of each island with se asian mainland the recent sub faunas of sundaland kalimantan sumatra java and bali preserved broad connections with the se asian mainland during the latest glacial they are all balanced and show many mainland components alternatively wallacea sulawesi and the lesser sunda islands has always been geographically isolated from the mainland wallacea faunas thus remain unbalanced they lack large carnivores and endemic a significant turnover arrives throughout the region with pronounced global sea level recessions around 0 8 ma during the transition from early pleistocene ep to the middle pleistocene mp by way of comparison the palaeontological records of japan and taiwan also preserve this turnover with ep mp recessions bringing east asian mainland immigrants on java the earliest late pliocene to early pleistocene satir fauna indicates island conditions java became connected to the se asian mainland towards the end of the early pleistocene global cooling brought open woodlands on java an environment evidently preferred by homo erectus in the ci saat fauna and trinil h k fauna as ep mp sea level recessions created a wide corridor across the sunda shelf siwaliks and the se asian mainland terrestrial mammals invaded as is seen in the kedung brubus fauna the succeeding ngandong fauna maintains an open woodland character but shows some endemism homo erectus and stegodon trigonocephalus among others can be distinguished on a subspecies level the late pleistocene marks the earliest known tropical rainforest and the corresponding punung fauna is of chinese affinity with pongo hylobates and elephas maximus homo sapiens probably arrives at this point as well the youngest fossil faunas known from java are the still poorly known cipeundeuy fauna ca 30 ka and the holocene faunas from wajak and sampung while sulawesi and flores remained isolated throughout the quaternary only a limited number of terrestrial vertebrates arrived by crossing sea barriers endemic island faunas with pygmy elephantoids and giant tortoises were present during the early pleistocene ep mp sea level recessions allowed large to medium sized elephantoids to replace the dwarf species around the same time homo erectus appears on the island of flores modern faunas eventually replaced the middle pleistocene island faunas but the time frame has yet to be pinpointed sulawesi presents a unique case its current fauna holds no walanae representatives apart from the phalangers which must have come from the east the ancestors of all other large sulawesi land vertebrates fossil and extant reached the island by crossing the sunda sea as the south sulawesi fauna was stable until the middle pleistocene this area must have constituted a separate palaeo island some localized developments can be observed e g shortening of the metapodials in celebochoerus increasing hypsodonty in stegodon

discerning the timing and cause of historical mortality events in modern porites from the great barrier reef the life history strategies of massive porites corals make them a valuable resource not only as key providers of reef structure but also as recorders of past environmental change yet recent documented evidence of an unprecedented increase in the frequency of mortality in porites warrants investigation into the history of mortality and associated drivers to achieve this both an accurate chronology and an understanding of the life history strategies of porites are necessary sixty two individual uranium thorium u th dates from 50 dead massive porites colonies from the central inshore region of the great barrier reef gbr revealed the timing of mortality to have occurred predominantly over two main periods from 1989 2 4 1 to 2001 4 4 1 and from 2006 4 1 8 to 2008 4 2 2 a d with a small number of colonies dating earlier overall the peak ages of mortality are significantly correlated with maximum sea surface temperature anomalies despite potential sampling bias the frequency of mortality increased dramatically post 1980 these observations are similar to the results reported for the southern south china sea high resolution measurements of sr ca and mg ca obtained from a well preserved sample that died in 1994 6 2 3 revealed that the time of death occurred at the peak of sea surface temperatures sst during the austral summer in contrast sr ca and mg ca analysis in two colonies dated to 2006 9 3 0 and 2008 3 2 0 suggest that both died after the austral winter an increase in sr ca ratios and the presence of low mg calcite cements as determined by sem and elemental ratio analysis in one of the colonies was attributed to stressful conditions that may have persisted for some time prior to mortality for both colonies however the timing of mortality coincides with the 4th and 6th largest flood events reported for the burdekin river in the past 60 years implying that factors associated with terrestrial runoff may have been responsible for mortality our results show that a combination of u th and elemental ratio geochemistry can potentially be used to precisely and accurately determine the timing and season of mortality in modern massive porites corals for reefs where long term monitoring data are absent the ability to reconstruct historical events in coral communities may prove useful to reef managers by providing some baseline knowledge on disturbance history and associated drivers 2014 elsevier ltd all rights reserved

did panthera pardus linnaeus 1758 become extinct in sumatra because of competition for prey modeling interspecific competition within the late pleistocene carnivore guild of the padang highlands sumatra abstract on the island of sumatra the leopard panthera pardus became extinct during the late pleistocene several theories exist about the reasons why leopards could not subsist in sumatra while today national parks still bear tigers panthera tigris and asiatic wild dogs cuon alpinus one often debated theory is that the competition for prey was the reason for the extinction of leopards in sumatra the aim of our study is to model the impacts of competition for prey in the carnivore guild of the padang highlands in sumatra to test if competition pressure was sufficient to force the leopard to extinction in the first step we reconstructed the carnivore guild of the padang highlands based on fossils collected by dubois in the three cave sites of sibrambang djamboe and lida ajer in the second step we developed and applied an agent based model based on population density prey spectrum and daily meat intake and simulated different scenarios of competition among the sumatran predators we simulated the reconstructed guild and further tested scenarios with the absence of guild members to see under which circumstances leopards could have survived in sumatra simulation of the reconstructed carnivore guild revealed that in fact the leopard could have been driven to extinction by competition from other carnivores excluding one of the competing medium sized cats or the asiatic wild dog leads to the survival of the leopard in our simulations interestingly our model demonstrates that humans and tigers were not the strongest competitors for leopards because their exclusion from the scenarios does not conclude with the survival of leopards in our simulations according to our results the presence of two medium sized cats and the asiatic wild dog in combination with the small litter size of the leopard were the main reasons why the leopard could not tolerate the competition for prey in the padang highlands in sumatra and thus became extinct in sumatra

a 135 000 year record of vegetational and climatic change from the bandung area west java indonesia sedimentological and palynological analyses of sediment cores from the intramontane bandung basin west java indonesia provide a first palaeoclimatic record for the indonesian region covering continuously the last 135 000 years our data on palaeosol development indicate anomalously dry conditions for the final part of the penultimate glacial period around 135 000 yr b p and very warm and humid interglacial conditions from 126 000 to 81 000 yr b p during the transition to the last glacial period around 81 000 yr b p freshwater swamp forest of the bandung plain was replaced by an open swamp vegetation dominated by grasses and sedges indicating a change to considerably drier conditions possibly related to reduced moisture uptake by the nw monsoon as a consequence of lower sea levels at the onset of glacial conditions a strong reduction in asplenium ferns from 81 000 to 74 000 yr b p suggests that drier conditions may also have occurred in the mountains of the bandung area while increased numbers indicate that from 74 000 to 47 000 yr b p it was slightly wetter again inferred depression of montane vegetation zones and reduced fern percentages suggests distinctly cooler and possibly drier climatic conditions prevailed in the bandung area from 47 000 to approximately 20 000 yr b p for the last glacial maximum 4 7 c lower temperatures are recorded

the upper cretaceous carbonates of the gargano murge region southern italy a model of platform to basin transition the outcrops in gargano murge region are good examples of the upper cretaceous carbonate systems of the peri adriatic area they enable the architecture and the processes of the platform to basin transition to be studied in detail the platform carbonates are juxtaposed to the deeper marine carbonates by the intermediary of a faulted scarp the base of slope is characterized by bioclastic and conglomeratic aprons interbedded with pelagic mudstones the outer shelf domain which was the prolific source of rudistid bioclastic aprons is not preserved the platform is mainly built of mud dominated transgressive systems tracts whereas highstand systems tracts are developed as bioclastic base of slope aprons the volume of the resedimented bioclasts largely exceeds the volume of missing outer shelf indicating that carbonate production and sediment bypass are more critical for this stratigraphic response than carbonate erosion the lowstands which were controlled by tectonic deformations are characterized by base of slope breccia and blocks eroded from the shelf edge this erosion resulted in the progressive retreat of the shelf edge the best potentials for hydrocarbon reservoir are found in the bioclastic base of slope aprons formed during the cenomanian and maastrichtian highstands this model is considered as an analog for the hydrocarbon reservoirs formed by the deep marine deposits of cretaceous tamabra limestone in the gulf of mexico

testing the savannah corridor hypothesis during mis2 the boh dambang hyena site in southern cambodia abstract the boh dambang karstic site in southern cambodia kampot province is a mammal bone rich deposit in a hyena site very few hyena sites have been recovered in the pleistocene of southeast asia thus little information is known about the foraging abilities of hyenas during that period and their decline in the region while the other hypercarnivores tiger leopard and dhole persisted until present day to constrain the site we applied luminescence red tl and single grain osl esr and u th dating methods to the sediments and faunal teeth respectively the resulting age estimates suggest that the site represents an accumulation of a young deposit with faunal teeth in the range of 25 18 ka that was last exposed to sunlight between 8 and 7 ka and an older deposit containing older teeth 100 80 ka that have been eroded from the upper caves in the system and incorporated into the younger deposit thus the faunal age of 25 18 ka mis2 provides the best estimate for the age of the hyena site during lgm 26 5 19 ka we analysed the assemblage of isolated teeth in terms of taxonomic diversity and abundance the role of bone accumulators either carnivores or rodents has been precised through a taphonomic analysis diet was reconstructed through measurement of 13 c values of tooth enamel the taphonomic analysis reveals that the hyenas were the main bone accumulators at boh dambang porcupines were aslo a factor in the accumulation of remains the results show that the spotted hyenas hunted large sized herbivores 600 kg in a mixed environment dominated by grassland these data along with evidence from other pleistocene faunas from southeast asian mainland in terms of prey preference of hyenas rhinoceroses versus large bovines also reveal marked differences in relation to habitat type possible causes of the decline of the spotted hyena in the indochinese sub region hypercarnivory high trophic level comparable foraging strategies with hunters gatherers and climatic changes are tentatively proposed at this point

a sustainable review of the middle pleistocene benchmark sites including the ailuropoda stegodon faunal complex the proboscidean point of view abstract the different ecologies times of extinction and last stand of both elephas and stegodon in south east asia cover almost two million years in the middle pleistocene both taxa belong to the complex ailuropoda stegodon this regional complex is considered to have a chronological significance and further palaeoecological palaeobiogeographical or biochronological studies use this assemblage as a benchmark nevertheless such studies do not provide sufficient information regarding site formation and duration to be consistent enough to do so at an appropriate resolution mis timescale focussing attention on the occurrence of proboscideans a critical review of the robustness of the geological taphonomical and chronological data of middle pleistocene faunal assemblages suggests the necessity to undertake a deep reappraisal of this biochronological benchmark recommendations were provided in the 1980s not to use mixtures of faunal assemblages and progress in geochronology for two decades is available nevertheless a review of proboscideans suggests the necessity of a severe revision leading to scepticism concerning the use of the ailuropoda stegodon complex as an ecological marker extended to other taxa this review casts serious doubts on former and current paleoecological modellings and studies

on the sedimentological origin of down core variations of bulk sedimentary nitrogen isotope ratios 1 the bulk sedimentary nitrogen isotopic composition of two cores from nearby sites on the northern slope of the south china sea site 17940 and ocean drilling program odp site 1144 differs by up to 2 during the last glacial period given their close proximity both core sites are located in the same biogeographic zone and nutrient regime and it is thus unlikely that this offset is due to a true gradient in surface ocean conditions in an attempt to resolve this offset we have investigated the possible effects of two sedimentological parameters that can affect bulk sedimentary 15n namely the variable contribution of inorganic n to bulk n in the sediment and the grain size dependence of bulk 15n we find that neither effect singly or in combination is sufficient to explain the significant 15n offset between the two down core records by elimination the most likely explanation for the observed discrepancy is a different origin of both the organic and inorganic nitrogen at each site this study adds to the growing body of evidence highlighting the complex nature and origin of the sedimentary components in sediment drifts such as odp site 1144

platform margin collapses and sequence stratigraphic organization of carbonate slopes cretaceous eocene gargano promontory southern italy we describe the sequence stratigraphic organization and the associated sedimentological characteristics of cretaceous to eocene slope and base of slope carbonate successions the study area is located in the gargano promontory which belongs to the stable foreland of southern italy the succession consists of three superimposed depositional sequences separated by major unconformities the upper two sequences are clear examples of sequence stratigraphic organization in fact they both start with huge megabreccia wedges lst followed upward by thin pelagic units tst and a thick package of calciturbidites and debrites that alternate with pelagic mudstone hst the cretaceous highstand systems tract is clearly arranged in a number of coarsening upward cycles while the eocene one which also comprises a toplap shallow water unit is not the gargano stratigraphic palimpsest and the entire margin of the apulia platform show remarkable similarities with present day carbonate platform margins and slopes where irregular convex bankward embayments suggest large scale failures it is clear that classic sequence stratigraphic organization can result from simple platform dismantling having no or little time relation with global sea level fluctuations in fact as the margin failure lst interrupts the carbonate production a period of starvation tst along the entire slope and base of slope follows necessarily finally when the margin once again becomes active and productive sediment exportation starts again and the system begins to prograde hst

the late pleistocene duoi u oi cave in northern vietnam palaeontology sedimentology taphonomy and palaeoenvironments this paper describes new fossil materials recovered at the duoi u oi site in december 2003 by a vietnamese french japanese team the duoi u oi cave is located in man duc village 25 km of hoabinh city in northern vietnam it belongs to a karstic network developed in a dark grey micritic marine limestone dated from the lower to the middle triassic the sedimentary fill produced a rich mammalian fauna essentially composed of isolated teeth of middle to large sized mammals artiodactyla perissodactyla proboscidea carnivora rodentia primates and characteristic of late pleistocene the results of the duoi u oi fieldwork are of great interest for the following reasons 1 the biochronological age of the fauna is consistent with 230 th 234 u 238 u dating from the calcitic floors 6673 ka the duoi u oi fauna is thus the oldest well dated modern fauna known for the southeast asian mainland 2 in terms of sedimentology the analysis of the formation of the fossiliferous breccia and that of the processes of deposits shows a close relation between the karstic deposits inside the cave and the deposits in the alluvial terraces the observation of three levels of alluvial terraces associated with three caves situated at 62 10 and 3 m above the present alluvial plain suggests that exokarstic and endokarstic sediments evolved together 3 in terms of palaeobiogeography duoi u oi is the continental fauna showing the strongest resemblance with the late pleistocene faunas from indonesian islands punung gunung dawung lida ajer sibrambang and djambu caves this implies that at the time of duoi u oi ca 70 ka the sundaland was mainly characterised by faunas of modern aspect 4 the analysis of major taphonomic factors that led to the mammal assemblage reveals a combination of selective agents selective role of predators and porcupines selective destruction of age classes for some species selective preservation of fossils due to the deposition processes in the karstic network which contribute to the poor representation of the diversity of the fauna no arguments show that humans present at duoi u oi might have a possible role in the taphonomic process 5 the palaeoenvironmental reconstruction based on the composition of the faunal assemblage suggests a forested area and some open habitats under warm and humid conditions

changes in monsoon and ocean circulation and the vegetation cover of southwest sumatra through the last 83 000 years the record from marine core bar94 42 abstract we present the palynological record from deep sea core bar94 42 taken offshore of southwest sumatra in the indian ocean refinement of a previous age model for the core has been made using 7 additional radiocarbon ages and 29 additional oxygen isotope measurements these analyses have substantially improved the previously published chronology which has enabled revision of the results of sedimentological studies of the core the pollen and re interpreted biogenic and terrigeneous data were used to reconstruct monsoon circulation and vegetation of southwest sumatra over the last 83 000 years 83 kyr during marine isotope stage mis 5a southwest sumatra was covered by rainforest with open herbaceous swamps lining river courses and surrounding lakes the se component of the monsoon was stronger than the nw component resulting in a humid climate with a short dry season during mis 4 conditions were drier fire activity increased and the monsoon was generally weaker this latter pattern persisted until mis1 the vegetation was most open during mis 3 between 52 and 43 kyr identifying this phase as the driest of the last glacial an increase in montane trees from 52 kyr indicates the onset of cooler conditions which lasted until the transition to mis 1 at about 11 9 kyr after 43 kyr an everwet climate gradually developed as monsoonal circulation intensified and the se monsoon component became stronger during this time closed canopy rainforest became dominant regionally over southwest sumatra increased monsoonal activity during the early holocene resulted in increased precipitation river runoff sediment discharge and offshore sediment transport from the continental shelf

speleothem derived asian summer monsoon variations in central china 54 46 ka the oxygen isotope signature delta o 18 of stalagmite si3 collected from shizi cave in north east sichuan province provides an asian summer monsoon asm record in central china for the period 54 46 ka the si3 delta o 18 record clearly shows a negative delta o 18 excursion centred around 49 4 ka which was reported in hulu cave in east china but not identified in the speleothem records from south west china as a whole this record displays a higher coherence with the two hulu records from east china than with the speleothem delta o 18 records from south west china suggesting that at 54 46 ka central china was influenced more by the east asian summer monsoon than by the indian summer monsoon it also displays a significant negative delta o 18 excursion at 47 5 46 6 ka which is not clearly documented in two other speleothem delta o 18 records previously reported from south west china this suggests that details of the greenland interstadial 12 warrant further investigations in future in monsoonal china the si3 delta o 18 record displays more significant centennial scale variations than the other four speleothem delta o 18 records from east and south west china which may be due to the fact that the study site is closer to the north west boundary of the asm and more sensitive to variations of the asm than east and south west china copyright c 2011 john wiley sons ltd

characteristics of pleistocene megafauna extinctions in southeast asia the extinction of large bodied taxa from the pleistocene in southeast asia is examined although the chronological resolution of these extinctions is poor and number of excavations in the region relatively few broad characteristics of these extinctions can be described many taxa which became extinct appear to have been endemic to regions within southeast asia while some taxa which experienced extinction or severe range reduction occurred in several regions members of the latter group include proboscideans stegodon and palaeloxodon the pygmy hippopotamus hexaprotodon the orangutan pongo hyenas crocuta and hyaena the giant panda ailuropoda tapirs tapirus and megatapirus rhinoceroses rhinoceros and the giant asian ape gigantopithecus the loss of these species cannot be assigned to a single cause rather their disappearance is likely tied to both climatic and human agents unlike other regions which experienced megafauna extinctions eustatic changes in sea level in southeast asia seems to have been an important factor

pollen distribution in hemipelagic surface sediments of the south china sea and its relation to modern vegetation distribution abstract this paper analyses the distribution of pollen in the surface sediments of the south china sea as recorded in 28 samples from the area 6 09 20 07 n and 112 05 119 45 e at water depths of 329 4307 m pollen concentrations range from 444 kgrains g dry wt on the lower part of the continental slope in the northeast to zero in the central basin below 4000 m water depth pollen distribution patterns in the concentration and percentage isopolls incorporating data from the literature reflect the routes and mechanisms of pollen transport pollen source areas and considerable systematic differences between north and south the northern scs is distinguished by very high concentrations due to the high production and effective long distance transport of pine pollen and fern spores the maximum of their concentration occurs in the north adjacent to the convergence of the bashi and taiwan straits rather than near the estuaries of big rivers and stretches as a saddle from ne to sw consistent with the direction of the ne winter monsoon and sea current this pattern implies that pine pollen and fern spores adapted to wind transport and water flotation come from the northeast through the straits borne on the winter monsoon and sea current forced by it their source areas should cover large regions probably including south and southeast china most pollen of tropical and subtropical broad leaved trees found in the northern part of the scs occur in low concentrations however these concentrations decrease uniformly offshore implying a fluvial discharge from nearby lowlands in south china in the southern part of the scs pollen of tropical and subtropical broad leaved trees predominate total pollen concentrations however are much lower only 1 10 of those of the northern part the greatest concentrations occur offshore north borneo and decrease toward deep water suggesting fluvial input from relatively local sources on the adjacent islands e g borneo

vegetation and climate change in west java indonesia during the last 135 000 years abstract sedimentological and palynological analyses of two sediment cores from the intramontane bandung basin java indonesia provide the first palaeoclimatic record for the indonesian region covering the last 135 000 years our data indicate anomalously dry conditions for the penultimate glacial and very warm and humid conditions during the last interglacial during the last glacial period fresh water swamp forests of the bandung plain were replaced by open swamp vegetation dominated by grasses and sedges indicating a change to considerably drier climatic conditions possibly as a consequence of lower sea levels at the onset of glacial conditions for the last glacial maximum temperatures 4 7 c lower than at present are recorded

co evolution of monsoonal precipitation in east asia and the tropical pacific enso system since 2 36 ma new insights from high resolution clay mineral records in the west philippine sea clay mineralogical analysis and scanning electron microscope sem analysis were performed on deep sea sediments cored on the benham rise core md06 3050 in order to reconstruct long term evolution of east asian summer monsoon easm rainfall in the period since 2 36 ma clay mineralogical variations are due to changes in the ratios of smectite which derive from weathering of volcanic rocks in luzon island during intervals of intensive monsoon rainfall and illite and chlorite rich dusts which are transported from east asia by winds associated with the east asian winter monsoon eawm since luzon is the main source of smectite to the benham rise long term consistent variations in the smectite illite chlorite ratio in core md06 3050 as well as odp site 1146 in the northern south china sea suggest that minor contributions of eolian dust played a role in the variability of this mineralogical ratio and indicate strengthening easm precipitation in se asia during time intervals from 2360 to 1900 kyr 1200 to 600 kyr and after 200 kyr the easm rainfall record displays a 30 kyr periodicity suggesting the influence of el nino southern oscillation enso these intervals of rainfall intensification on luzon island are coeval with a reduction in precipitation over central china and an increase in zonal sst gradient in the equatorial pacific ocean implying a reinforcement of la nina like conditions in contrast periods of reduced rainfall on luzon island are associated with higher precipitation in central china and a weakening zonal sst gradient in the equatorial pacific ocean thereby suggesting the development of dominant el nino like conditions our study therefore highlights for the first time a long term temporal and spatial co evolution of monsoonal precipitation in east asia and of the tropical pacific enso system over the past 2 36 ma

rapid oscillations in western north america vegetation and climate during oxygen isotope stage 5 inferred from pollen data from santa barbara basin hole 893a abstract chronologically controlled high resolution 200 yr average sampling interval pollen data from a core in the santa barbara basin sbb provide evidence of millennial scale climate variability on the southern california coast from 70 to 140 ka b p the first climate event inferred from a brief reversal in the glacial interglacial shift from montane conifer to lowland oak assemblages occurred during the oxygen isotope stage ois 6 5 transition in ois 5e oak dominated assemblages imply conditions similar to or slightly warmer than present cooler conditions that gradually replaced the relatively stable warm mediterranean climate that continued across the ois 5e 5d transition ended abruptly just before the end of ois 5d warming inferred from oak expansion continued in ois 5c this lengthy cyclic sequence of high amplitude warming events which peaked below interglacial values extended into the first part of ois 5b similar oscillations occurred in ois 5a these pollen data that are directly correlated with isotopic data from the same sediment samples from hole 893a support previous observations that the last interglacial sensu stricto on the west coast of north america was correlative with oxygen isotope substage 5e in addition pollen data show that significant warming events reflected in terrestrial vegetation also occurred in different background states of the climate system during processes of ice growth as well as ice decay

mammal community structure of sundanese fossil assemblages from the late pleistocene and a discussion on the ecological effects of the toba eruption abstract the mammal community structure of four sundanese fossil sites from the late pleistocene are examined and compared to those of modern communities three sites from indonesia punung sibrambang and lida ajer show a community structure more similar to each other than to modern sundanese communities niah caves exhibits a structure entirely consistent with modern communities taphonomic bias and lower species richness in the indonesian sites may be the cause of these differences however there is reason to believe that the differences observed are at least in part a result of the environmental conditions under which these late pleistocene communities formed if so they represent an alternative stable state of community structure to that seen in later and modern communities if this scenario holds modern community structure in sundaland would have formed sometime between 128 118 ka and 45 39 ka these changes could therefore be the result of the toba eruption although it seems more likely they stem from environmental fluctuations accompanying glacial interglacial cycles mammal species in southeast asia seem particularly resistant to any effects of the toba eruption particular attention is focused on the orangutan which despite being in the immediate vicinity of toba before and after its eruption appears to have suffered no significant effects these observations have implications for theories suggesting the toba eruption resulted in a population bottleneck and altered the course of human evolution

the great arc of dispersal of modern humans africa to australia abstract during the late pleistocene anatomically modern humans amh dispersed out of africa across the continents their routes obeyed the limitations placed on any large terrestrial mammal dependent on daily drinking water following certain climate permissive corridors amh first spread north with game across the sahara to the levant during the eemian interglacial c 125 ka but failed to continue to europe then occupied by neanderthals the savannah ecosystem in north africa and the middle east then dried up and amh vanished from the levantine fossil record being replaced there by neanderthals later amh successfully left africa as a single group by the southern route to india the added ability to make short but deliberate open water crossings allowed them first to cross the mouth of the red sea from eritrea and subsequently wallace s line to reach the isolated sahul continent at least by 48 000 years ago and possibly by 60 50 000 years ago they only finally arrived in europe from south asia around 45 50 000 years ago probably linked to climatic amelioration during ois 3

biogeography and migration routes of large mammal faunas in south east asia during the late middle pleistocene focus on the fossil and extant faunas from thailand abstract thailand has long held a key position in south east asia because of its location at the boundary of the indochinese and sundaic provinces the major biogeographical regions of south east asia these provinces are distinct climatically floristically and faunistically the present day limit between them is located at the kra isthmus in peninsular thailand previous studies of the javanese large mammal fossil faunas and the recent study of fossil large mammal faunas from thailand strengthen the hypothesis of a continental migration route in contrast with the insular hypothesis via taiwan and the philippines during the late middle late pleistocene period thailand was even part of this migration route during the glacial periods the faunal exchanges were favored by the emersion of a huge continental shelf called sundaland south east asian continental area connected to borneo and indonesia islands by land bridges when the sea level was low no geological biogeographical or paleobiogeographical evidence supports the hypothesis of a migration route via taiwan and the philippines analysis of the extant and late middle pleistocene large mammal faunas carnivora primates proboscidea and ungulata points out the antiquity of the indochinese and sundaic provinces this idea is also supported by the fact that mainland faunas already displayed modern character whereas the javanese faunas were mainly composed of endemic forms however the occurrence of the extinct species elephas namadicus found in a malaysian site tambun indicates that the limit between the two provinces if not close to the present place was located more southward than today possibly in peninsular malaysia it is also confirmed by the presence of northern species such as ailuropoda melanoleuca baconi and crocuta crocuta ultima in late middle pleistocene sites of thailand in fact because of climatic cooling that occurred in the northern hemisphere during the pleistocene the northern faunas had to move southward to our knowledge the hypothesis of the antiquity of the south east asian provinces with a boundary south of the present day one is mentioned here for the first time previous biogeographical studies were based mainly on insular data from the philippine archipelago geological and mainly present day zoogeographical data but also from indonesia and borneo paleontological data however the recent discovery of thai large mammal faunas from late middle pleistocene allows to bridge the gap in the fossil record between the northern faunas of south east asia and the southern ones these thai faunas are characterized mainly by extant forms but some are today absent from the thai territory ailuropoda melanoleuca crocuta crocuta pongo pygmaeus sus cf barbatus rhinoceros cf unicornis cervus eldii

vegetation and climate history since the last interglacial in kurota lowland western japan abstract the pollen record of a long core from the kurota lowland of central honshu in western japan provides a continuous vegetation and climate history from beyond 120 000 to 25 000 yr bp the chronology is based on widely dispersed tephra and six conventional 14c dates prior to 120 000 yr bp forests were composed predominantly of abies tsuga picea and pinus haploxylon which indicate a cold climate probably corresponding to oxygen isotope stage 6 during the last interglacial around 120 000 yr bp cryptomeria japonica was dominant in forests with a small amount of evergreen oaks the early stage of the last glacial period is characterised by dominance of c japonica with two increases at 105 000 and 90 000 80 000 yr bp of pinaceous conifers and cool temperate deciduous broad leaved trees between 70 000 and 60 000 yr bp pinaceous conifer vegetation developed indicating a dry and cold climate and this was succeeded by a cool temperate deciduous broad leaved forest composed mainly of fagus crenata and deciduous oaks indicating a wet and cool cold climate from 55 000 to 40 000 yr bp temperate coniferous forests composed of c japonica and cupressaceae associated mainly with tsuga and deciduous oaks occurred after 40 000 yr bp mixed forests of c japonica tsuga and cool temperate deciduous broad leaved trees such as fagus crenata and deciduous oaks prevailed in a wet and cool climate at 28 000 yr bp an abrupt decrease of c japonica and development of forests composed of tsuga pinus haploxylon and betula with some deciduous broad leaved trees imply climatic deterioration to the lgm the vegetation history since the lgm has been revealed previously at iwaya site in kurota lowland time series of these pollen records can be correlated with the marine oxygen isotope stages 1 through 6

precipitation sealing and diagenesis 1 experimental results during burial and diagenesis of granular aggregates significant permeability reduction may be induced by the formation of low temperature authigenic minerals to quantitatively assess the importance of this process we have conducted a series of hydrothermal flow through experiments using deionized water and labradorite quartz sand all experiments were conducted in a modified triaxial apparatus configured to allow continuous permeability measurements under most of the conditions tested significant permeability reduction is observed with no concurrent decrease in porosity the overall permeability reduction sometimes exceeds 1 order of magnitude over 4 days and is positively correlated to temperature and deviatoric stress scanning electron microscope observations together with data from additional experiments show that the observed permeability reduction is entirely a result of secondary mineral growth si and al concentrations in the postexperiment fluids are also correlated to temperature and stress confirming the link between the chemical state of the system and permeability behavior in all experiments permeability reduction is fastest early and levels off in the late stages to explain the permeability behavior as a function of time a conceptual model is developed in which precipitation of authigenic minerals is rapid at early times while dissolution of quartz and labradorite is most active as the system approaches equilibrium the components necessary for secondary mineral formation are liberated at a lower rate thereby causing precipitation to slow although authigenic mineral formation does not reduce total pore space in these experiments there is a reduction in effective porosity which results in permeability reduction

thermal ionization mass spectrometry u series dating of a hominid site near nanjing china mass spectrometric u series dating of speleothems from tangshan cave combined with ecological and paleoclimatic evidence indicates that nanjing man a typical homo erectus morphologically correlated with peking man at zhoukoudian should be at least 580 k y old or more likely lived during the glacial oxygen isotope stage 16 similar to 620 ka such an age estimate which is similar to 270 ka older than previous electron spin resonance and alpha counting u series dates has significant implications for the evolution of asian h erectus dentine and enamel samples from the coexisting fossil layer yield significantly younger apparent ages that of the enamel sample being only less than one fourth of the minimum age of nanjing man this suggests that u uptake history is far more complex than existing models can handle as a result great care must be taken in the interpretation of electron spin resonance and u series dates of fossil teeth

geo environmental mapping using physiographic analysis constraints on the evaluation of land instability and groundwater pollution hazards in the metropolitan district of campinas brazil geo environmental terrain assessments and territorial zoning are useful tools for the formulation and implementation of environmental management instruments including policy making planning and enforcement of statutory regulations they usually involve a set of procedures and techniques for delimitation characterisation and classification of terrain units however terrain assessments and zoning exercises are often costly and time consuming particularly when encompassing large areas which in many cases prevent local agencies in developing countries from properly benefiting from such assessments in the present paper a low cost technique based on the analysis of texture of satellite imagery was used for delimitation of terrain units the delimited units were further analysed in two test areas situated in southeast brazil to provide estimates of land instability and the vulnerability of groundwater to pollution hazards the implementation incorporated procedures for inferring the influences and potential implications of tectonic fractures and other discontinuities on ground behaviour and local groundwater flow terrain attributes such as degree of fracturing bedrock lithology and weathered materials were explored as indicators of ground properties the paper also discusses constraints on and limitations of the approaches taken

zinc isotopes in late pleistocene fossil teeth from a southeast asian cave setting preserve paleodietary information stable carbon and nitrogen isotope ratios of collagen from bone and dentin have frequently been used for dietary reconstruction but this method is limited by protein preservation isotopes of the trace element zinc zn in bioapatite constitute a promising proxy to infer dietary information from extant and extinct vertebrates the 66zn 64zn ratio expressed as 66zn value shows an enrichment of the heavy isotope in mammals along each trophic step however preservation of diet related 66zn values in fossil teeth has not been assessed yet here we analyzed enamel of fossil teeth from the late pleistocene 38 4 13 5 ka mammalian assemblage of the tam hay marklot thm cave in northeastern laos to reconstruct the food web and assess the preservation of original 66zn values distinct enamel 66zn values of the fossil taxa 66zncarnivore

u series dating of soda straw stalactites from excavated deposits method development and application to blanche cave naracoorte south australia this study aimed to further test the method reported by st pierre et al 2009 to develop robust chronologies of deposits in limestone caves through u th uranium thorium or u series dating of soda straw stalactites the chronology of fossil bearing deposits at blanche cave was further constrained with thermal ionisation mass spectrometry tims u th dating of 17 additional soda straw stalactite samples and results were compared to recalibrated c 14 ages of charcoal the results support the assertion that soda straw stalactites can provide ages close to the time of sediment deposition and may be used as reliable chronological markers particularly for periods reaching or beyond the radiocarbon dating limit the application of an enhanced cleaning technique facilitated the reduction of detrital th in samples significantly increasing age accuracy and precision additionally u th age accuracy and precision was increased through the application of site specific measured u th ratios to correct for the detrital th 230 component in samples c 2011 elsevier ltd all rights reserved

millennial pulsing of environmental change in southern california from the past 24 k y a record of indo pacific enso events century long variations in coastal california vegetation inferred from polliniferous sediments deposited in the santa barbara basin record a succession of brief 14 c yr b p ka these millennial scale pulses many of which correspond with western great basin hydrological fluctuations are also linked to events of southwest monsoon intensification in southern asia we suggest that these correlative high frequency variations in the asian summer and northeast pacific winter climates may reflect submillennial scale el nino southern oscillation enso type forcing involving water vapor transport over the indian and pacific oceans

quantification of pore structure and its effect on sonic velocity and permeability in carbonates carbonate rocks commonly contain a variety of pore types that can vary in size over several orders of magnitude traditional pore type classifications describe these pore structures but are inadequate for correlations to the rock s physical properties we introduce a digital image analysis dia method that produces quantitative pore space parameters which can be linked to physical properties in carbonates in particular sonic velocity and permeability the dia parameters derived from thin sections capture two dimensional pore size domsize roundness aspect ratio ar and pore network complexity poa comparing these dia parameters to porosity permeability and p wave velocity shows that in addition to porosity the combined effect of microporosity the pore network complexity and pore size of the macropores is most influential for the acoustic behavior combining these parameters with porosity improves the coefficient of determination r2 velocity estimates from 0 542 to 0 840 the analysis shows that samples with large simple pores and a small amount of microporosity display higher acoustic velocity at a given porosity than samples with small complicated pores estimates of permeability from porosity alone are very ineffective r2 0 143 but can be improved when pore geometry information poa r2 0 415 and domsize r2 0 383 are incorporated furthermore results from the correlation of dia parameters to acoustic data reveal that 1 intergrain and or intercrystalline and separate vug porosity cannot always be separated using sonic logs 2 p wave velocity is not solely controlled by the percentage of spherical porosity and 3 quantitative pore geometry characteristics can be estimated from acoustic data and used to improve permeability estimates

late quaternary paleoceanography of the south china sea surface circulation and carbonate cycles paleoceanographic information from 34 sediment cores is summarized to investigate the glacial interglacial variations in sea surface circulation and late quaternary carbonate cycles in the south china sea judging from the distribution pattern of deposition rates the enormous terrigenous supply by rivers is responsible for the high rate of hemipelagic sedimentation which was even higher during glacial periods paleotemperature maps based on transfer function temperature estimates have revealed a e w gradient of sst for glacial summer and a s n gradient for glacial winter and this agrees well with the clockwise surface circulation in summer and counterclockwise in winter during glacials as shown by a preliminary computer modelling the high resolution paleotemperature curves of core v36 3 from the northern slope show an abrupt cooling event which may belong to the younger dryas carbonate percentage in sediments and preservation of foraminifers and pteropods are used to study the carbonate cycles in the marginal sea it turns out that two mechanisms are functioning there being a basin with large drainage areas vast amount of river borne terrigenous input dilutes carbonate and its intensification during glacial decreases the glacial cac03 being a basin connected with the pacific the fluctuations of lysocline ccd and acd in the scs are related to those in the pacific ocean and dissolution is strengthened at interglacial thus above the present ccd the dilution factor predominates and the atlantic cycles are produced below the present ccd the dissolution factor prevails resulting in the pacific pattern of carbonate cycles

mesogenetic dissolution its role in porosity development in carbonate reservoirs models of porosity formation in carbonate rocks have stressed subaerial exposure and attendant shallow meteoric diagenesis porosity formation also occurs in deep burial or mesogenetic settings as a result of dissolution enlargement of preexisting pores porosity enhancement and creation of new pore systems brines charged with organic acids carbon dioxide and or hydrogen sulfide derived from organic matter diagenesis and thermochemical sulfate reduction are the likely fluids causing significant mesogenetic dissolution enhanced and newly created mesogenetic pore types can mimic pore types formed in shallow meteoric environments and therefore the mesogenetic origin of some porosity may go unrecognized

the effect of chemical and physical processes on the acoustic properties of carbonate rocks carbonate rocks have major economic significance 60 of the world s oil reserves lie in carbonate reservoirs and the potential for additional gas reserves is huge however the relationship in carbonates between measured geophysical data and rock properties is complex due to the large variety of textures that arise during postdepositional diagenesis and to the chemical processes i e dissolution and replacement by newly formed phases that characterize carbonate forming minerals most experimental and theoretical rock physics research has focused on siliciclastic and shaly rocks however applying insights gained from clastics to carbonates is rarely straightforward and thus is questioned in the literature

mortality curves and population structures of late early miocene rhinocerotidae mammalia perissodactyla remains from the beon 1 locality of montreal du gers france abstract mortality curves are a valuable tool to study taphonomy and to infer population structure in ancient communities however they rely on the precise determination of ontogenetic ages of individual animals which is often uncertain for fragmentary and isolated fossil remains in this paper we develop a new protocol to construct mortality curves for fossil rhinocerotids using both tooth rows and isolated teeth based on dental wear we tested and calibrated this protocol using 29 skulls and 18 jaws of extant rhinoceroses diceros bicornis rhinoceros sondaicus and r unicornis we then applied it to four extinct rhinocerotid species from the late early miocene locality of beon 1 of montreal du gers sw france the teleoceratines brachypotherium brachypus and prosantorhinus douvillei the basal rhinocerotine plesiaceratherium mirallesi and the early elasmotheriine hispanotherium beonense findings allow us to estimate population structures of these rhinocerotids based on the percentage of juveniles subadults and adults the mortality curves of beon 1 rhinocerotids reveal several major periods of vulnerability birth weaning sexual maturity and middle late adulthood when compared to extant populations d bicornis ceratotherium simum and r unicornis and other ancient case studies miocene of usa pleistocene of southeast asia and france mortality rate curves from beon 1 are similar in early and late life however they lack the increased socially driven mortality that is observed between 25 and 50 of the potential lifespan in some populations of d bicornis and in the miocene teleoceratine teleoceras proterum the population structures of pr douvillei pl mirallesi and h beonense are close to those of extant populations of d bicornis in contrast adult specimens of b brachypus are overrepresented at beon 1 similarly to aphelops malacorhinus at love bone bed usa probably due to taphonomical bias it is important to note that considering isolated or associated teeth alone results in significant differences in mortality curves and population structures at beon 1 hence both samples should be studied

the vegetation and climate at the last glaciation on the emerged continental shelf of the south china sea studies on the dispersal mechanism and source areas of pollen from hemipelagic sediments recovered from the continental slopes of the south china sea scs reveal that vegetation existed on the exposed shelves at the last glacial maximum lgm and the latter part of the marine isotope stage 3 at the low sea level stand artemisiadominated grassland covered the northern continental shelf and tropical lowland rainforest and mangroves grew on the southern shelf sunda land consequently the climate in the northern scs must have been much colder and drier during the last glacial period compared to the present sunda land experienced only a marginally lower temperature but was not drier than today the enhanced contrast between the northern and southern parts of the scs in vegetation and climate during the lgm may be ascribed at least partly to the strengthening of winter monsoon during the last glacial period 2000 elsevier science b v all rights reserved

glacial conditions in the northern molucca sea region indonesia abstract palynological planktonic foraminiferal and stable isotope data from a sediment core in the northern mollucca sea have been used to evaluate regional glacial climatic and hydrographic conditions the palynological record shows that in glacial time the climate was drier than today indicating a weakened influence of the northwesterly winds at that time the drier climatic conditions at glacial time were associated with a higher lapse rate which together with a lower sea level resulted in a large expansion of the lower montane oak forests on the nearby island of halmahera glacial mollucca sea surface water salinities were probably higher than today while glacial surface water temperatures might have been close to present day values the deep chlorophyll maximum dcm layer in the northern molucca sea at glacial time was more productive and cooler than today probably the result of the inflow of cooler and nutrient enriched subtropical lower water from the pacific the less asymmetrical high latitude ice coverage at glacial time and the particularly strong increase in the pole to equator thermal gradient on the northern hemisphere provides theoretical evidence that the intertropical convergence zone itcz shifted equatorwards and oscillated over a more narrow latitudinal range than today this inferred configuration of the itcz at glacial time however fails to explain the observed increased aridity in the study area at that time we propose therefore that the drier glacial climatic conditions are related to a possible disturbance in the el nino southern oscillation enso system