摘要: |
晚更新世末期(12000-25000a BP)为玉木冰期最盛时期,气候寒冷而干燥,极地冰流的扩展使世界海面大幅度下降,我国东部沿海海面下降约130-160m,黄海、东海陆架裸露成陆。在寒冷干燥的气候条件下,陆架沉积物不仅受到强烈的机械风化作用,而且受到来自北方强大干冷气流的吹扬作用,陆架沉积物在这些外力因素的作用下破坏解体,形成一系列的风沙地貌和风沙沉积,反映出晚更新世末期南黄海陆架沙漠化景观。根据本区浅地层测量断面分析研究的结果,并结合柱状岩芯及钻孔资料,初步揭示了本地区晚更新世末期的古地貌特征。 |
关键词: 晚更新世末期、南黄海中部陆架、古地貌特征 |
DOI: |
分类号: |
基金项目:中国科学院海洋研究所调查研究报告第3216号 |
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THE PALEOGEOMORPHIC FEATURES OF THE MIDDLE PART OF THE SOUTH YELLOW SEA SHELE IN THE LAST STAGE OF LATE PLEISTOCENE |
Zhang Minghan, Yu Hongjun
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Institute of Oceanology,Chinese Academy of Sciences
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Abstract: |
Records of the shallow layer profiler in the comprehensive survey of the South Yellow Sea in 1993 and regional drilling bores and cores data were used in this work which studied the shelf shallow stratum depositional structure of the Holocene and late Pleistocene, identified the paleogeomorphic and sediment types at that time, and revealed the paleogeomorphic features of the South Yellow Sea shelf in the last stage of late Pleistocene. The records of the shallow layer profiler showed that the desertized area was characterized by widespread buried dune, aeolian nonclined sandy texture, aeolian depression and platform. The different shelf desertizational sediment types can be divided into aeolian sandy sediments, and mixed accumulation and aeolian dust deposits around the desertization area. The research results indicated that the South Yellow Sea shelf underwent desertication under the cold-dry climatic conditions in the last stage of late Pleistocene and formed a series of the aeolian landforms and sediments. |
Key words: PALEOGEOMORPHIC FEATURES,SOUTH YELLOW SEA SHELE, LAST STAGE OF LATE PLEISTOCENE |