Environmental Dynamics of Organic Accumulation for the Principal Paleozoic Source Rocks on Yangtze Block

详细信息   

• 责任者：Chen Daizhao (Key Laboratory of Petroleum Resource Research ; Institute of Geology and Geophysics ; Chinese Academy of Sciences ; Beijing 100029 ; China) ; Wang Jianguo
• 刊名：Chinese Journal of Geology
• 出版年：2011
• 卷期：46(1)
• 关键词：烃源岩 ; source rocks ; 扬子地区 ; Yangtze Region
• 页码：p.5-26
• 图表：12 illus., 88 refs.
• 分类号：1003
• issnNo：ISSN0563-5020
• isbnNo：CN11-1937/P

摘要

On Yangtze block，there are three regionallydistributed highquality source rock horizons：the Lower Cambrian，Upper Ordovician-Lower Silurian and Permian (Middle and Upper Permian). The Lower Cambrian source rocks mainly consist of the lower black chert (Liuchapo Formation) and upper siliceous shales，carbonaceous shales (or stone coals) (Niutitang Formation). During the Early Cambrian，extensive hydrothermal activities occurred on the Yangtze platform margins extending ca. 2 000～3 000 km long，and released vast amounts of silica-rich fluids into the ocean，inducing extensive silica precipitation off the platform margin through basin. Simultaneously，a large quantity of H₂S and greenhouse gases (CO₂，CH₄)and metalliferous anoxic fluids were vented into oceanic waters and atmosphere，leading to an apparent elevation of atmospheric CO₂ concentration and large-scale rise of sealevel.