摘要: |
根据80年代在黄海多次综合性地质调查资料,对采获样品进行粒度、矿物、化学成分等分析和对比。结果证明,黄海在2-3万年前的晚更新世低海面时,同今日的陆地一样,曾存在着黄土沉积。尽管全新世大规模海慢发生之后,黄土沉积受到了一定的破坏和改造,但它们仍大量地残留在黄海西部的海底,其中又以海州湾一带的分布面积最大。由于长期处于海底,已发生了某种程度的变化,但其基本性质和特征仍同陆上的黄土相似。 |
关键词: 黄土 晚更新世 黄海 |
DOI: |
分类号: |
基金项目:国家自然科学基金资助,49276257号 |
附件 |
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LOESS DEPOSIT IN YELLOW SEA DURING LATE PLEISTOCENE |
Zheng Tiemin
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Institute of Oceanology, Acadcmia Sinica, Qingdao 266071
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Abstract: |
Loess is a typical Quaternary deposit on land in northern China, but existed in the Yellow Sea in late Pleistocene as surveys in the 1980s recovered its remains on the seafloor. Priliminary study on grain size, mineral content and chemical component shows that typical loess on the seafloor distributes over a large area in Haizhou Bay between Qingdao and Lianyungang and is usually found under modern sediment and relict sediment and some even emerges from the seafloor surface. The loess on the seafloor is composed mainly of silt and clay fractions. Its major chemical compositions and some trace elements are similar to those of Malan loess on the China mainland. The radiated structure, and composition of calcareous nodules in loess on the seafloor and that on land are also similar. 14C dating proved that the seafloor loess was formed in 18 000 - 23 000a B. P. on land. Since the loess had been under the seafloor for a long time, some changes have occurred in it. |
Key words: Loess, Late Pleistocene, Yellow Sea |