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THE RECORD OF YOUNGER dryas EVENT IN EOLIAN SAND DEPOSIT IN QAIDAM BASIN

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Chinese Geographical Science 1999年第1期9卷 92-95页

作者：曾永年马海州沙占江李玲琴李珍曹广超 Centre for Resources and Environment Research of Qinghai-Xizang Plateau Department of Geography Qinghai Normal University Xining P. R. China

The Qaidam Basin is one of the main areas where the desert of the Qinghai-Xizang Plateau is distributed.According to the envirotunment records and the age of stratigraphy in Xiaxitai section in southeast part of Qaidam Basin,this paper reached the following conclusions: the desert development, formation of the cold-dry climate, evolution of natural environment and their reverse changes occurred frequently since the late glacial. In eolian sand deposits, the Youngerdryas event clearly appeared, which manifesed a dry-cold climatic period. Now there are two different opinions about theclimatic effect of Younger dryas. According to the predecessors’ research and the field work of the authors, it is considered that the Younger dryas event not only exists in different climatic zones of China, but the manifests the unitary drycold climatic effect.

关键词： Younger dryas event eolian sand deposit Qaidam Basin

The Record of Younger dryas Event in Lake Sediments From Jalai Nur,Inner Mongolia

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Chinese Science Bulletin 1994年第10期39卷 831-835页

作者：王苏民吉磊羊向东薛滨马燕胡守云 Lake Sediment and Environment Laboratory Nanjing Institute of Geography and Limnology Academia Sinica Nanjing 210008 PRC

Younger dryas has been highlighted by paleoclimatologists in recent years becauseof the abrupt change of temperature and CO2 concentration within a short timeof several centuries or even less. At present, there exist virtually two viewpointsabout the event: one is that Younger dryas only affects Circum-North Atlanticregion. The influx of the floating iceberg and the melt water from Arctic area to theNorth Atlantic Ocean due to the global warming in the Late Glacial suppressed

关键词： lake record Younger dryas climatic change Hulun Lake.

The Younger dryas in the West Pacific marginal seas

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Science China Earth Sciences 1996年第5期39卷 522-532页

作者：汪品先卞云华李保华黄奇瑜 Laboratory of Marine Geology Tongji University Shanghai 200092 China Nanjing Institute ot" Geology and Paleontology Chinese Academy of Science Nanjing 210008 China Department of Geology Taiwan University Taipei China

The occurrence and nature of the Younger dryas (YD) abrupt climatic event in the West Pacific marginal seas are discussed on the basis of 15 sediment cores. This event has been found in all these cores studied with a high-resolution stratigraphy and proved to be common to the West Pacific region. As shown by the isotopic and micropaleontologic analyses, the YD, dated by C-14 at about 11000 to 10000 a B.P., is a brief event of sea surface cooling in winter season following a fresh-water pulse about 12000 a B.P. The 'apparent regression' of the YD recorded in the Changjiang River delta and the Sea of Japan agrees with the interpretation that the YD is a period of slowed sea level rising between two phases of rapid rising. Both the winter surface water cooling and the increasing salinity in the YD imply a strengthening of the winter, but not summer monsoon circulation. This major climatic event in the marginal seas must have had profound impact on the adjacent continent.

关键词： Younger dryas West Pacific marginal sea deglaciation paleoceanography.

Younger dryas Comet 12,900 BP

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Open Journal of Geology 2017年第2期7卷 193-199页

作者： Hermann G. W. Burchard Department of Mathematics Oklahoma State University Stillwater OK USA

Deep troughs in Lake Superior support the hypothesis of Younger dryas Boundary (YDB) comet impact 12,900 BP. The impact theory explains the megafauna extinction, a black mat across the Northern hemisphere, nanodiamonds, platinum and iridium, and the enigmatic Carolina Bays (CB). While the CB were thought to predate Clovis cultural remains, but this must now be seen as spurious as the CB occur on Long Island, an LGM terminal moraine & on end-glacial flood plains, according to Allen West. The CB sand rims are exceptionally pure quartz with large phenocrysts, and also they exude hydrogen (H). This suggests origin from deep granitic plutons, the granite typically being over-saturated with silica. When the Russian Kola Peninsula Superdeep Borehole had reached 40,000 ft, H was boiling from the borehole. This H is among volatiles copiously dissolved in the mantle, from the primitive solar nebula. The granite is from the Lake Superior Province. Lakes Superior, Michigan, Huron & Ontario have deep holes, reaching to below sea level. Bathymetry exhibits a ~145 km circular contour in Eastern L. Superior, where deep troughs occur, eroded in breccias infilling impact explosion cavities many kms deep, as much as 15 to 35 km, the comet fragments coming in from the NW, with the holes lined up along the trajectory. This was an oblique impact with an extremely low angle of incidence, so the ejected granite quartz sands ended up in the CB along the Eastern seaboard principally.

关键词： Younger dryas Comet Hypothesis Great Lakes Comet Impact Carolina Bays Quartz Sands

Planktonic foraminifera and sea surface temperature (SST) of the Xisha Trough, South China Sea since Last Glaciation

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Science China Earth Sciences 2003年第1期46卷 1-9页

作者：江茂生李学杰 Institute of Geology and Geophysics Chinese Academy of Sciences Laboratory of Marine Geology Tongji University

The high-resolution analysis on the carbon and oxygen isotopes and planktonic fo-raminifera of core SA12-19 dated with 14C approach in the Xisha Trough of South China Sea indi-cates that sediments are attributed to oxygen isotope stages 1—3 (stage 3 is not included com-pletely), during the late-glacial to post-glacial periods. The sea surface temperature (SST) of each sample is calculated based on palaeoecological transfer functions (FP-12E). The results reveal a gradual thermocline increase in this area during oxygen isotope stages 1—3 e.g. a temporal thermocline deepening in the middle Holocene. During the Holocene, the SST was 23.3—27.2℃ in winter, 28.8—29.8℃ in summer. During oxygen isotope stage 2, the SST was 21.4—24.4℃ in winter, 28.1—29.0℃ in summer; and 21.9—25.2℃ in winter, 28.5—29.3℃ in summer during oxygen isotope stage 3. The SST in winter during oxygen isotope stage 2 was 2—6℃ lower than that of stage 3. During the transitional period, a Younger dryas Event, standing for a rapid cli-mate return, occurred obviously.

关键词： South China Sea, oxygen isotope, planktonic foraminifera, sea surface temperature, 'Younger dryas Event'.

两高分辨率黄土剖面末次冰消期气候事件的差异探讨

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中国沙漠 2007年第2期27卷 177-181页

作者：管清玉潘保田高红山李琼李炳元王均平苏怀兰州大学西部环境教育部重点实验室中国科学院地理科学与资源研究所甘肃北京100101

高分辨率黄土剖面的获取使我们对亚轨道时间尺度上的气候事件的研究成为可能。通过对六盘山东、西部两个高分辨率黄土剖面与GRIP冰芯记录的对比研究,我们发现两剖面都捕捉到了末次冰消期内的Youngerdryas事件与Heinrich-1事件及Bφlling... 详细信息

高分辨率黄土剖面的获取使我们对亚轨道时间尺度上的气候事件的研究成为可能。通过对六盘山东、西部两个高分辨率黄土剖面与GRIP冰芯记录的对比研究,我们发现两剖面都捕捉到了末次冰消期内的Youngerdryas事件与Heinrich-1事件及Bφlling和Allerφd事件,并且它们在时间上与冰芯的结果较为一致。更为重要的是,这些亚轨道时间尺度上的气候事件在东西两剖面内存在较大差异:Heinrich-1事件在西面沙沟剖面的烙印较东面的王官剖面要深;对于Bφlling和Allerφd事件,沙沟剖面较王官剖面的波动要多;在沙沟剖面,Younger dryas的结束是一种突变行为,而在王官剖面中则是一种渐变行为;此外,沙沟剖面比王官剖面表现出更大的波动幅度和更多千年尺度上的快速波动。初步推测上述差异是由高、低纬地区对它们影响的不同所造成的。

关键词：末次冰消期 Younger dryas BФlling和AllerФd

新仙女木事件及全新世早中期降温事件——来自洱海湖泊沉积的记录

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气候变化研究进展 2007年第Z1期3卷 41-44页

作者：周静王苏民杨桂山 Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Changzhou Institue of Environmental Protection Changzhou 213022 Jiangsu China Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

Three cold events (the Younger dryas, 9.4 ka cal BP, 5.8 ka cal BP) since the 13 ka cal BP in Erhai (EH) Lake catchment, Yunnan Province, were analyzed using the Total Organic Carbon (TOC) series of the EH core. By comparison of the EH core, Qinghai Lake core and Guliya ice core, differences of these cold events were determined. Erhai Lake's responses to the global cold events were lagged in time and weakened in intensity in comparison with Qinghai Lake's. The latitude location of Erhai Lake and the obstruction of Tibetan Plateau may in part explain the differences. However, the remarkable cold event of 8.2 ka cal BP in the Guliya ice core was absent in the records of Erhai Lake and Qinghai Lake. Power spectrum analysis of the TOC proxy series shows that there were three kinds of millennial cycles, i.e. 5 ka, 2.3 ka, and 1.5 ka, in climate changes in Erhai Lake, which reveal the responses of climate to suborbit cycles.

关键词： Younger dryas Holocene cold event Erhai Lake