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上扬子地区广泛发育上奥陶统五峰组和下志留统龙马溪组富有机质页岩,前人研究较少涉及其岩相类型和沉积过程对主要地质事件的响应.细粒沉积物高精度层序地层学研究表明,晚奥陶世至龙一段充填沉积期,经历了3次大的地质事件,形成了2个三级层序(五峰组层序Sq1和龙一段层序Sq2)、12个准层序组和13个笔石带.在生物地层约束的等时格架中,识别出火山喷发事件形成的富碳、富有机硅的硅质页岩相,底流侵入事件及陆源输入浊流事件沉积的贫碳、贫有机硅的混合质页岩相和泥质页岩相,建立了五峰组-龙马溪组富有机质页岩的成因模式,该套页岩主要为该时期的火山喷发(包括冰期和生物绝灭)、底流侵入和陆源输入等地质事件导致的古气候、古海洋等各要素协同作用的结果.
The Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation organic-rich shale have been extensively developed in the Upper Yangtze region, and the previous studies rarely involve the response of the lithofacies types and sedimentary processes to major geological events. The study of sequence stratigraphy shows that during the filling-depositional period from the Late Ordovician to Long Formation, it experienced three major geological events and formed two tertiary sequences (Sq1 and Sq2) Quasi-sequence group and thirteen pen-stone belts in the isochronal framework constrained by biostratigraphy, identify carbon-rich, siliceous shale facies formed during volcanic eruptions, underflow intrusion, Flow events deposition of poor carbon, poor organic silicon mixed shale facies and shale shale facies, established Wufeng Formation - Longmaxi Formation organic-rich shale genesis pattern, the set of shales mainly for the period of volcanic eruptions (Including glacial and extinction), the influx of underflow and the input of terrestrial events and other geological events caused by the ancient climate, paleoceanography and other elements of synergy results.