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Yumidong (Corn Cave) is a newly discovered Paleolithic site in the Three Gorges region of central China. Numerous Paleolithic artifacts have been excavated from the sedimentary deposits of the cave in association with faunal remains attributed to the Middle-Late Pleistocene Ailuropoda - Stegodon fauna of southern China. To establish the chronology of the sedimentary sequence (>5 m thick), 14C dating was applied to bone and charcoal samples (n = 6); the U-series method was used to date in situ precipitated speleothems (n = 12), transported speleothem samples (n = 6) and 18 subsamples of a fossil tooth; and the coupled ESR/U-series method was used to date fossil teeth (n = 6). The derived dates were combined using a hierarchical Bayesian approach to generate a unified chronostratigraphy for the Yumidong sequence. In our Bayesian analyses, the 14C and coupled ESR/U-series dates were considered to provide direct age estimates for the target layers, while the U-series dates of the in situ precipitated speleothems and fossil tooth were used as minimum age constraints and those of the transported speleothem fragments as maximum age constraints. The Bayesian analyses provided robust time intervals for the archeological layers: L2-Upper (14–23 ka), L2-Lower (27–63 ka), L3 (106–171 ka), L4 (140–192 ka), L10 (157–229 ka), L11 (181–256 ka), and L12 (214–274 ka) with a probability of 95%, allowing the establishment of a ∼300 ka long geological and archeological history for the Yumidong site and placing it as a reference site for Paleolithic cultural evolution in the Three Gorges region from the late Middle Pleistocene to Late Pleistocene. [ABSTRACT FROM AUTHOR]

Abstract: Coral microatolls have been long used as precise indicators of past sea level, but their use for precise definition of detailed sea-level fluctuations is still rare. Here we report twelve high-precision thermal ionization mass spectrometric 230Th ages for twelve rims of five mid-Holocene microatolls from an emerged reef terrace at Leizhou Peninsula, northern South China Sea. This is a tectonically stable area, enabling us to reconstruct both the timing and trajectory of local sea-level fluctuations accurately. The elevations of these microatoll rims and cores were accurately determined relative to the surface of modern living microatolls at the same site. The results indicate that the sea level during the period of 7050–6600 yr bp (years before AD 1950) was about 171 to 219 cm above the present, with at least four cycles of fluctuations. Over this 450 yr interval, sea level fluctuated by 20–40 cm on century scales. [Copyright &y& Elsevier]

The article presents abstracts of several studies on environmental geochemistry. Some of the abstracts presented include "Biogeochemical Cycling of Nutrients in Karstic Catchments, Southwestern China: Linkages to Changes of Eco-Environments," by Congqiang Liu and "Emerging Organic Contamination in China," by Guibin Jiang and colleagues.

Along the main boundary fault of the central Tibetan Shuang Hu graben, two well-preserved fluvial terrace surfaces are vertically offset by ∼1.3 m (terrace I) and ∼14.8 m (terrace II). Using thermal ionization mass spectrometry (TIMS), we have determined 48 230Th–234U–238U ages of small (10–40 mg) samples from pedogenic carbonate rinds on clasts in the terrace deposits. Based on textural, microstratigraphic and geochemical criteria, we conclude that the U-series ages of innermost-rind samples provide reliable ages of 16.4±1.9 ka for terrace I, and 233.1±9.3 ka for terrace II. This constrains the average rate of vertical displacement along the normal fault to be 0.079±0.011 mm/yr during the past ∼16 kyr, and 0.064±0.007 mm/yr during the past ∼233 kyr. Combining these results with slip-rate estimates for other normal faults along the graben margins indicates that the cumulative vertical displacement on all normal faults did not exceed ∼0.3 mm/yr during the late Quaternary. This new rate from central Tibet is distinctly lower than the rate of 1.9±0.6 mm/yr inferred for normal faults bounding the Yadong-Gulu graben system in southern Tibet, consistent with more pronounced and common graben development in southern Tibet. We therefore suggest that normal faulting in southern Tibet is largely controlled by local processes, and that the age of its initiation is not a valid proxy for uplift of the Tibetan plateau, as has been widely assumed. Our data also place chronologic constraints on the termination of periglacial conditions in central Tibet during the last three interglaciations. Rind formation appears to have been relatively continuous on clasts in terrace I from ∼16 ka. Clast rinds from terrace II, in contrast, are characterized by three main episodes of rind growth that are widely separated in time. The earliest and least well-preserved episode started at 233.1±9.3 ka, a second episode occurred at 131.8±7.8 ka, and a third episode was approximately coeval with rind formation in terrace I after 16.4±1.9 ka. In each case, the age of onset of carbonate rind accumulation coincides with independently estimated ages of global deglaciation. Accordingly, we conclude that periglacial conditions in the central Tibetan plateau terminated synchronously with early stages of global warming following the last three glacial maxima, and that fluvial aggradation, terrace formation, and pedogenic carbonate accumulation in terrace soils ensued rapidly. [Copyright &y& Elsevier]