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Xingyong Xu, First Institute of Oceanography, State Oceanic Administration (China)
Peiying Li, First Institute of Oceanography, State Oceanic Administration (China)
Hongjun Yu, First Institute of Oceanography, State Oceanic Administration (China)
Naisheng Li, First Institute of Oceanography, State Oceanic Administration (China)
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Shandong Hills (34¡ã40'~37¡ã45'N, 116¡ã24'~122¡ã30'E) including Mt. Taishan (1545 m a.s.l), Mt. Laoshan (1133m a.s.l), Mt. Mengshan (1156m a.s.l) are located in Shandong Province, East China. Widely distributed traces of Quaternary glaciation have been recognised over the Shandong Hills, and highly varied glacial Quaternary landforms and sediments are well preserved. Among them, Laoshan is the most typical area, with a complete spectrum of glacial phenomena. Major erosional forms include glacial troughs, horns, ar¨ºtes, cols, polished surfaces, roches moutonn¨¦es and striations. Glacial depositional forms include erratics, moraine dams, medial moraines, lateral moraines, terminal moraines, moraine-built coast and glaciofluvial fans. In addition, deglaciation landforms were produced by high water-discharge, including potholes, troughs, various shaped stones, and a moraine-dammed glacial lake in which varves and glaciofluvial sediments were deposited. Glacier reconstructions indicate that during Early Pleistocene glaciation, the altitude of the snowline in the eastern part of Laoshan region was lower than 100 m a.s.l. Many moraine dam-producing glaciers reached the Yellow Sea, which today are being eroded by marine agents, resulting in a unique moraine-dominated coast with islets capped by residual boulders. The discovery of low-altitude moraine dams suggests that the major part of original moraine systems are currently buried in this region. The nature of continental glaciation of the Pleistocene Epoch in mountainous regions of Shandong is manifested by the coastal boulders and potholes found in Laoshan and nearby Chashan (in Rongcheng of Shandong). During coldest period, the temperature was 13¡ãC, or even 16¡ãC, lower than that of today. Palynological assemblages in the moraine, and associated sediment grain-size distribution, indicate the nature of glaciation [UNLEAR SENTENCE ¨CPLEASE CHECK REVISION]. The numerous traces of glaciation found in the region demonstrate the close relationship between palaeoglaciation and sedimentation in the shelf environment. Many ancient river channels and large troughs that are buried beneath the sea on the continental shelf east of China were developed by an outburst flood during deglaciation. The large amount of loosely compacted Quaternary sediment in the Yellow Sea may have originated from several interglacial periods. Available data show that the glacigenic sediment from the last glacial period contributed substantially to Yellow Sea sedimentation. Increasing discoveries of traces of glaciation in the study area indicate several large-scale Quaternary glaciations, which could be considered as an important factor in estimating the impact on the global sea-level fluctuation. This level might be lower than previously believed, at -160 m according to recently acquired knowledge.
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