摘要
本文在实测剖面的基础上,通过薄片观察、粒度分析和阴极发光测试等手段,以沉积相的研究为切入点,将沉积作用和构造作用紧密联系,分析了留山盆地的沉积特征和构造性质。研究表明,留山盆地上三叠统沉积相主要为扇三角洲相,经历了早期的退积作用和晚期的进积作用。沉积相的演化和源区分析综合表现出,留山盆地是一个孤立的陆相盆地,沉积物来源主要为盆地周围的造山带物质。盆地演化经历了盆地形成阶段、平稳沉降阶段、快速沉降阶段和快速充填阶段,其构造动力与盆地周缘的构造作用强度相呼应。盆地性质可能为压坳性盆地,进而推测留山盆地是华北与扬子板块在晚三叠世碰撞期间向南大规模推覆而产生的背驼式盆地。
Based on measured geological profile and experiments including thin-section, grain size analysis and cathodeluminescence in Liushan Basin, the characteristics of sedimention and tectonic environment are investigated, by studying sedimentary facies firstly and combining sedimentary processes with tectonism tightly. The studies indicated that the sedimentary facies of Upper Triassic series in Liushan Basin was mainly fan delta, retrogradational fan deltas at first and then progradational fan deltas. Evolution of sedimentary facies and analysis of provenance indicate synthetically that Liushan Basin is an isolated basin,the sediments mainly come from the orogenic belt surrounded the basin. The evolution of basin contains four stages ： basin formation, subsidence smoothly, subsidence quickly and filling quickly, corresponding to the tectonic dynamics. The type of Liushan Basin may be the compressional, and it can be presumed further that Liushan Basin was a piggy basin companying the North China Block in collision with Yangzi Block during the Late Triassic.
出处
《地质科学》
CAS
CSCD
北大核心
2010年第3期718-733,共16页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
中石化重大前瞻性项目"华北西南部晚三叠世-新近纪岩相古地理研究与编图"(编号:CW800-07-2s-165-01)
河南理工大学博士基金项目(编号:648511)联合资助
关键词
留山盆地
晚三叠世
沉积特征
构造环境
Liushan Basin, Late Triassic, Sedimentary characteristics, Tectonic environment
