摘要: |
利用油浸系统鉴定法对南海中东部286 个表层沉积物样品63—125μm 粒级的矿物鉴定和分析结果表明, 沉积物中矿物种类丰富, 有57 种; 矿物组成以轻矿物为主, 重矿物含量较低; 与中国其他海区相比, 以铁锰微结核、磁铁矿、普通辉石和火山玻璃的高含量为特征。根据矿物来源和成因的研究, 可分为陆源碎屑矿物、自生沉积矿物、火山碎屑矿物、生物骨屑矿物和宇宙来源矿物5 类。为了定量地探讨沉积物中矿物组合及其空间分布, 根据特征矿物的相似性对286 个样品22种矿物变量进行Q-型聚类分析, 将南海中东部表层矿物分布划分为陆源、混合、自生、火山4 个矿物组合区。各组合区中矿物组成和含量上的变化反映了物质来源和沉积环境的差异。 |
关键词: 南海, 表层沉积物, 矿物组合区, 地质意义 |
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基金项目:国家海洋局海底科学重点实验室第2001-2号课题和“九五”国家专项海洋地质地球物理重大资助项目部分研究成果 |
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MINERAL ASSEMBLAGE PROVINCES FOR SURFICIAL SEDIMENTS OF THE CENTRAL-EASTERN SOUTH CHINA SEA AND THEIR GEOLOGICAL SIGNIFICANCES |
YANG Qun-Hui1, LIN Zhen-Hong2, ZHANG Fu-Yuan3, LIN Xiao-Tong2, JI Fu-Wu2
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1.Guang zhou Institute of Geodemistry, The Chinese Academy of Sciences;2.Ocean University of Qingdao;3.Key Lab of Submarine Geosciences, SOA
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Abstract: |
Minerals from the very fine sand fraction ( 63—125μm) in surface sediments have been identified and analyzed from 286 stations in the central-eastern South China Sea. The results reveal that the mineral species are very abundant. Fifty-seven mineral species occur in surface sediment in the central-eastern South China Sea. The minerals mainly consist of the light mineral and the heavy mineral contents are lower. Compared with the other seas in China, the central-eastern South China Sea is characterized by relatively high ferromanganese micronodule, magnetite, augite and volcanic glass contents. According to their provenances and geneses, the minerals can be divided into five types: the terrigenous clastic mineral, authigenic mineral, volcanogenic clastic mineral, biogenic mineral and cosmogenic mineral. In order to discuss quantitatively the mineral assemblages and their spatial distribution, a Q-mode cluster analysis with 286 sediment samples and twenty-two mineral variables has been carried out. As a result, minerals in the central-eastern South China Sea have been divided into four mineral assemblage provinces: the terrigenous mineral assemblage province, mixed mineral assemblage province, authigenic mineral assemblage province and volcanogenic mineral assemblage province. The variations of composition and content among the mineral assemblage provinces reflect the differences of their provenances and sedimentary environments. |
Key words: South China Sea, Surface sediments, Mineral assemblage provinces, Geological significances |