鄂尔多斯盆地上古生界高分辨率层序划分与煤聚积规律分析  

Analysis of high-resolution sequence stratigraphy and coal accumulation law of upper Paleozoic erathem in Ordos Basin

作　　者：李增学[1] 韩美莲[1] 魏久传[1] 余继峰[1] 李江涛[2] 吕大炜[1] 

机构地区：[1]山东科技大学地质科学与工程学院 [2]中国科学院广州地球化学研究所,广东广州510640

出　　处：《中国石油大学学报（自然科学版）》2008年第1期5-12,共8页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家重点基础研究发展规划项目(2003CB214608);教育部博士点基金项目(20050424001)

摘　　要：运用层序地层学的理论和高分辨率层序地层中基准面的研究方法,对鄂尔多斯盆地晚古生代盆地充填序列和高分辨率层序地层单元的划分以及该地区煤的聚积规律进行了研究。结果表明,鄂尔多斯盆地上古生界由陆表海盆地、盆地转换时期、大型板内坳陷盆地3类充填沉积序列构成。该区本溪组至石盒子组可划分成9个三级层序和4个二级层序。在高分辨率层序地层格架内盆地的聚煤作用是随着盆地充填演化发生迁移的,其中第5号煤层沉积时期是聚煤作用最强的时期,而第3号煤层形成时聚煤作用的范围已经退缩。聚煤作用的强度变化与富煤单元的迁移受盆地充填沉积时的沉积体系发育及废弃特点控制。The sequence stratigraphic theory and method, in particular, the base-level method of high-resolution sequence stratigraphy were used in the study of infilling series of Late Paleozoic erathem in Ordos Basin. The high-resolution sequence strati- graphic units were classified to figure out the coal accumulation law within the basin. The results indicate that upper Paleozoic erathem are composed of three parts： the epicontinental sea basin infilling, infilling during basin transform and the infilling series of large depression basin within plate. The series from lower Benxi formation to upper Shihezi formation was classified into four 2nd-order and nine 3rd-order sequences. The coal accumulation law and the migration of coal-rich components were ana- lyzed within the high-resolution sequence stratigraphic framework. The results suggest that coal accumulation can migrate with the basin being filled and evolving, and that the coal accumulation was the strongest one at the period when coal seam 5 was deposited and shrunk when coal seam 3 was deposited. The variation in coal accumulation strength and the migration of coal-rich unit are subject to the development and abandon of the sedimentary system during the infilling of the basin.

关 键 词：鄂尔多斯盆地 古生界 高分辨率层序 基准面旋回 煤聚积规律 

分 类 号：P539.2[天文地球—古生物学与地层学] P618.11[天文地球—地质学]