Study on Double Causes and Paleoseismic Pulse Cycle of the Neoproterozoic Ball-Pillow Structure in Shou County, Anhui Province
详细信息
- 责任者：Wang Xi (Geological Science and Engineering College ; Shandong University of Science and Technology ; Qingdao 266590 ; China) ; Wang Mingzhen
- 刊名：Acta Geologica Sinica
- 出版年：2013
- 卷期：87(6)
- 关键词：古地震 ; paleoearthquakes ; 软沉积物变形 ; soft sediment deformation ; 安徽 ; Anhui Province
- 页码：p.823-831
- 图表：illus., 33 refs.
- 分类号：0803
- issnNo：ISSN0001-5717
- isbnNo：CN11-1951/P
摘要
The silt～fine sandstone sediments of lower Neoproterozoic Sishilichangshan Formation in Shouxian County of Anhui Province was found to host a set of ball-pillow shaped soft-sediment deformation structures with double causes.The study of outcrop profiles has shown that the soft-sediment deformation structures formed from earthquake disaster event in shallow slope of the shelf edge.As slump gravels fell into the surface of soft silty sediments , primary ball-pillow shaped bodies formed due to tremor shaking stress of earthquake.And then , under the pulsation and cycled earthquake shaking effect , the gravel continued to sink into the bottom of liquefied sand layer , forming the formation of a ball-pillow shaped deformed structure with double caused stress.Our study suggests that the deposition deformation has undergone synsedimentary deformation process , such as earthquake , tsunamis , slump , slide fold , tremors shaking subsidence , liquefaction draining , gravels screen directional aligned , and the soft plastic tighten deformation , etc.It is also revealed that the earthquake is characterized by multiple cycle geological event , which contains a fore-shock stage , the main shock stage and after-shock stage.The intensity of seismic energy should have exceeded the magnitude 7and this provides important information for the study of sediments deformation and the pulsation and cycle process of marine seismite.