OSL dating of sediments from deserts in northern China

OSL dating of sediments from deserts in northern China

Yellabidde Cave, Northern Swan Coastal Plain, Southwestern Australia Aboriginal History of Australia Aboriginal people have lived in Australia for at least 60, years, arriving by boat from south Asia at about that time, or possibly earlier. By 35, BP to 25, BP ancestral Aboriginal People had occupied all major environmental zones of Sahul Greater Australia , from the large islands off the northeastern coast of Papua New Guinea in the equatorial region, to the southernmost part of Tasmania. At the time of the arrival of Europeans in Australia it was declared an unoccupied land, as the Aboriginal People didn’t practice agriculture, so the colonists could take over without even consulting the locals. The Aboriginal People were believed by some of those Europeans to be at best, like children, who needed to be protected from themselves as well as everyone else. Others regarded them as sub-human, so there was no problem treating them as though they were animals, especially when colonisation got under way and colonists wanted to take over their hunting territory for raising cattle and sheep, or farming. They were mostly tolerated as long as they didn’t try to stop pastoralists taking their land, when they got in the way, they were often treated like animals that ate the colonists’ crops or killed their cattle for food. It has since been realised that they did indeed farm the land, even the parts that were unusable by the colonists, and for a very long time. It has been called fire-stick farming. During their long period of occupation they developed a system of burning off limited areas at certain times of the year, that encouraged the grass growth, that supported the animals they hunted. So while they lived by hunting, over large parts of the continent it was in effect managed hunting.

ESR Dating of Sedimentary Quartz from Two Pleistocene Deposits Using Al and Ti-Centers

YinZhou Huang Field investigations including lake shoreline measurement and 14C chronology have been carried out on the Alxa Plateau to better understand the formation and evolution of the high lake levels in northwest China during the late Pleistocene. Comprehensive field investigations show that there are at least ten shorelines at different elevations at Juyan Lake, at least four on the northwest side of the Jilantai Salt Lake, and nine shorelines and one terrace on the northeast margin of Zhuye Lake.

Stratigraphic correlations and chronological evidence indicate that the paleo-lakes have the highest lake levels in Marine Isotope Stage MIS 3.

Aeolian samples from deserts in northern China were studied using the optically stimulated luminescence (OSL) of quartz and potassium (K) feldspar separates. K-feldspar has shown advantages over quartz for dating samples younger than years, due to its more homogeneous equivalent dose (De) values, higher internal dose rate and higher luminescence sensitivity to dose.

Godthelp in Hill, Robert S. White, , The Nature of Hidden Worlds: Australian Conservation Foundation, Melbourne. Michael Archer, Suzanne J. Gehling, Kathleen Grey, Guy M. Franklin, The revolution that didn’t arrive: Aboriginal History 9, Frith, Cape York Peninsula: A Natural History, Reed, D. Hobbs and Colin J. Marine Geology, 25,

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Publications Academic Profile David Thomas is a geomorphologist and physical geographer specialising in contemporary drylands and the Quaternary Period. Much of his research has been carried out in Africa, but he also conducts research in Arabia, Asia, India, North America and other dryland contexts. His research has often been multi- and interdisciplinary. On the one hand he has led interdisciplinary projects on desertification, land degradation, sustainable land use and climate change impacts; on the other he works on projects focussed on geomorphological processes, Late Quaternary environmental change, climate change science and environmental-climate interactions, with archaeologists, biologists, climate scientists and other physical geographers.

Gilbert and Kenneth Mason. Prior to returning to Oxford, where he was a student from for undergraduate, Cert.

South China is an important region for the investigation of the origin of modern humans and the dispersal of Homo sapiens in Asia. However, the accurate dating of Paleolithic sites, especially for open-air sites, in the region has been difficult due to the lack of datable materials like bones that were destroyed due to intense chemical weathering.

Publications Academic Profile Abi’s research interests lie within understanding the dynamics of dryland systems, including environmental change, landscape dynamics and groundwater resources. She is interested in these processes and dynamics over a range of timescale and applies techniques to address questions about whether groundwater aquifers are part of the active hydrological cycle and questions about the timing and forcing mechanisms of expanding and contracting Quaternary drylands.

Abi is currently working with Prof. Mike Edmunds and Prof. David Thomas, using pore-moisture in sand dune sediments in the Stampriet Basin, in the Kalahari in order to: She is currently developing this research theme following her pilot study undertaken during her Thesiger-Oman International Fellowship from the Royal Geographical Society. Abi continues to conduct research into the Quaternary palaeoenvironments of dryland areas, with a focus on the Namibian portion of the southern African subcontinent.

Currently, this involves luminescence dating of dune material in the Namib Sand Sea and reviewing the palaeoenvironmental and geomorphological history of that region. She aims to test the applicability of pore-moisture techniques to the large Namib Sand Sea dunes, in order to provide a palaeomoisture proxy. She was previously employed within Prof. Heather Viles’ Rock Breakdown Laboratory where she coordinated write-up of an English Heritage funded soft capping research project. Current Research The two broad themes of Abi’s research involve using chemical tracers in the pore moisture of surface sediments and the reconstruction of Quaternary landscape dynamics.

Chemical tracers as novel archives of groundwater recharge and palaeomoisture This research develops the use of chemical tracers in the pore moisture of near-surface sediments with the aim of improving understanding of dyland hydrological dynamics over both decadal-to-century and century-to-millennial timescales.

Abi is fortunate to be working with Prof.

Aeolian sedimentation in arid and semi-arid

He had been a middle school teacher geography for two years ; and stayed in Physical Research Lab in India hosted by Prof. As a scholar in Oxford University, he was entitled to dine at the high table in the college. Environmental change in arid and semi-arid areas the Tibetan Plateau, the Chinese Loess Plateau, deserts and salt lakes in north-western China, etc ; Chronology of human migration; Luminescence dating in both application and technique development. Lai enjoys his hobbies reading and sporting, etc.

Aeolian samples from deserts in northern China were studied using the optically stimulated luminescence (OSL) of quartz and potassium (K) feldspar separates. K .

Advanced Search Abstract All exposed rocks on Earth’s surface experience erosion; the fastest rates are documented in rapidly uplifted monsoonal mountain ranges, and the slowest occur in extreme cold or warm deserts—millennial submeter-scale erosion may be approached only in the latter. The oldest previously reported exposure ages are from boulders and clasts of resistant lithologies lying at the surface, and the slowest reported erosion rates are derived from bedrock outcrops or boulders that erode more slowly than their surroundings; thus, these oldest reported ages and slowest erosion rates relate to outstanding features in the landscape, while the surrounding landscape may erode faster and be younger.

We present erosion rate and exposure age data from the Paran Plains, a typical environment in the Near East where vast abandoned alluvial surfaces — km2 are covered by well-developed desert pavements. These surfaces may experience erosion rates that are slower than those documented elsewhere on our planet and can retain their original geometry for more than 2 m.

Major factors that reduce erosion converge in these regions: The 10Be concentrations in amalgamated desert pavement chert clasts collected from abandoned alluvial surfaces in the southern Negev, Israel representing the Sahara-Arabia Deserts , indicate simple exposure ages of 1. The 36Cl in carbonate clasts, from the same pavement, weathers faster than the chert and yields simple exposure ages of — ka or maximum erosion rates of 0. These ages and rates are exceptional because they represent an extensive landform.

The 10Be concentrations from samples collected at depth and optically stimulated luminescence OSL dating reveal a two-stage colluvial deposition history followed by eolian addition of 40 cm of silt during the past k. Our results highlight the efficiency of desert pavement armor in protecting rocks from erosion and preserving such geomorphic surfaces for millions of years. GeoRef Subject You do not currently have access to this article.

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Timing and Spatial Distribution of Loess in Xinjiang, NW China

Lion head in ivory, Kostenki 1. Despite being tiny, this sculpture is realistic and vivacious. Marl soft, chalky limestone , height 15 mm. Kunstkamera, St Petersburg Lion head. Ralph Frenken Source and text:

The sedimentary sequence and landscape of the Hobq desert was observed through twelve profiles along five N-S sections extending through the entire desert. Aeolian sands were found to overlie the alluvial, diluvial, and lacustrine sediments in this desert. Optically stimulated luminescence (OSL.

Received May 18; Accepted Feb 8. This article has been cited by other articles in PMC. Abstract Central Asia is one of the most significant loess regions on Earth, with an important role in understanding Quaternary climate and environmental change. However, in contrast to the widely investigated loess deposits in the Chinese Loess Plateau, the Central Asian loess—paleosol sequences are still insufficiently known and poorly understood.

Through field investigation and review of the previous literature, the authors have investigated the distribution, thickness and age of the Xinjiang loess, and analyzed factors that control these parameters in the Xinjiang in northwest China, Central Asia. The loess sediments cover river terraces, low uplands, the margins of deserts and the slopes of the Tianshan Mountains and Kunlun Mountains and are also present in the Ili Basin.

The thickness of the Xinjiang loess deposits varies from several meters to m. We consider persistent drying, adequate regional wind energy and well-developed river terraces to be the main factors controlling the distribution, thickness and formation age of the Xinjiang loess. The well-outcropped loess sections have mainly developed since the middle Pleistocene in Xinjiang, reflecting the appearance of the persistent drying and the present air circulation system. However, the oldest loess deposits are as old as the beginning of the Pliocene in the Tarim Basin, which suggests that earlier aridification occurred in the Tarim Basin rather than in the Ili Basin and the Junggar Basin.

Introduction The Chinese Loess Plateau CLP , with its continuously deposited loess-paleosol sequences, records the thickest, largest, oldest and most continuous aeolian deposits on Earth. Together with the marine sediments and polar ice cores, these deposits constitute one of the three most commonly used proxies in paleoclimate studies. Over the past two decades, this unique continental archive has been extensively studied with the goal to understand the history and cause of Asian aridification, dust transportation, East Asian circulation and Tibetan Plateau uplift [ 1 — 12 ].

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The geomorphology of desert dunes. Routledge, London and New York. Interpreting and modelling late Quaternary dune accumulation in the southern Arabian Peninsula. Quaternary Science Reviews, Allostratigraphy and Quaternary dune sediments: Not all bounding surfaces are the same.

Samples were from four deserts in northern China, namely Hulun Buir, Mu Us, Hobq and Horqin. The deserts are located in the semiarid climatic zone, controlled by the East Asian monsoon circulation. The deserts are located in the semiarid climatic zone, controlled by the East Asian monsoon circulation.

Geology 10Be terrestrial cosmogenic nuclide dating of alluvial surfaces in the Coachella Valley, southern California, shows two alluvial fan surfaces with ages of When combined with additional fan dates from the Mojave and Sonoran Desert climatic regimes, statistically relevant episodes of fan production in southern California and Baja California were identified by mean standard weighted deviance analysis. Three major episodes have been identified at These correlate well with the first 2 ka of glacial advance with the Sierra Nevada as established by dating of moraines and rock flour analysis of lake cores from Owens Lake.

These data suggest that regional climate rather than global climate or local tectonics influences the production, transport, and deposition of sediment onto fan surfaces in the Sonoran and Colorado Deserts. Regional data on the ages of fan surfaces highlights a temporal link between the initiation of glacial advance and fan production.

Global climate changes initiate Sierra Nevada glaciations which in turn produce a response in sedimentary processes over regional-scale areas. This suggests changes in regional climate initiate fan production when sediment is mobilized due to increased rainfall, before vegetation anchors sediment. Furthermore, the model focused upon transitions into more humid climate appropriate for the Sonoran and Colorado Deserts may be applicable to areas of similar arid climate where precipitation levels clearly control the abundance of vegetation but not globally, and so a unifying global model for fan formation may not be possible.

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