The basin between the Yangtze and Cathaysia blocks has been extensively filled during Late NeoproterozicEarly Paleozoic, but the filling process and their relationship of basin evolution is unclear.A part of sandbody that has monotonous lithology and lack of sedimentary structure and fossils played an important role in the filling process, they are different in rock assemblage, sedimentary characteristics, and the detrital zircon ages with the relevant strata in the Yangtze area, we call it "the Cathaysia-typed sandbody" here for they are mainly developed around the Cathaysia block.Some new detrital zircon ages were obtained from these transitional sections, combined with previous studies and data, we trying to reconstruction the source supply and filling process of the basin through a quantitative and "point-line-surface" way, and then constrain its tectonic-sedimentary evolution process.The results shows that, at least during the Cryogenian to Silurian, the Cathaysia-typed sandbody have a trend to migrate towards Yangtze block（NW）:（1） In the Cryogenian, the front of sandbody reached Guiyang in Hunan, between Sizhoushan and Tianzidi Formation（Fm.）;（2） In the Ediacaran, migrated to the north of Yongfu in Guangxi, between Hongjiang and Peidi Fm.;（3） during Cambrian, to the Xinning in Hunan between Niutitang and Chayuantou Fm.;（4） from Ordovician to Silurian, the sand travel across the Jiangnan discontinuous island and reached the Meitan Fm.in Youyang, Chongqing.In particular, it can be furtherly divided into three stages during Early Paleozoic:（1）Cambrian-Early Ordovician, detrital sediments are derived from each shore side of the basin and exhibited a bilateral filling pattern;（2）Late Ordovician, supply of detrital sediments are disturbed, different source of detritals mixed in some central basin areas（like Xinning, Hunan）.（3）Silurian saw an unidirectional filling pattern, which is overwhelmed by the Cathaysia-typed sandbody derived from southeast of the basin.The detrital supply process implies that:（1） there is a source area becoming stronger in detrital supply during Late Neoproterozic-Early Paleozoic, implies a continuous land-uplift.（2） there is a process of shorten and steepen of basin floor and uplift of basin margin, which is linking to the uplift of Jiangnan Orogen, WuyiYunkai Orogen, and Gondwana.（3） The migration process does not support the model of a broad and mature ocean between the Yangtze and Cathaysia blocks during the Cryogenian to Early Palaeozoic.
类型: 国际会议
作者: Yaoyan HE,Zhijun NIU,Huazhou YAO,Fang SONG,Wenqiang YANG,Zhihong WANG
来源: 第一届亚洲古生物学大会—暨中国古生物学会成立90周年纪念 2019-11-17
年度: 2019
分类: 基础科学
专业: 地质学
单位: China University of Geosciences, Geological Survey Institute,WuhanKey Laboratory for Paleontology and Coevolution of Life and Environment,China Geological SurveyWuhan Center of Geological Survey,China Geological Survey
分类号: P542
页码: 29-30
总页数: 2
文件大小: 213k
下载量: 1
本文来源: https://www.lunwen90.cn/article/9a1233e2e3b5e3d6efc54127.html