梅河盆地聚煤古构造分析

Meihe Basin Coal-accumulating Paleostructure Analysis

中国大陆位于欧亚板块的东南部,受欧亚板块,库拉—太平洋板块与印度板块的三向不均衡作用,在中生代—新生代时导致中国东部发生郯庐断裂,梅河盆地为郯庐断裂在东北的一个分支——抚密断裂里的地堑—半地堑聚煤盆地。其构造格架是在盆地形成演化过程中,各个阶段构造叠加的结果,它包括先期的基底构造、同沉积构造、后期的改造构造。梅河盆地从形成到结束盆缘断裂(F1、F2)控制着盆地的沉积和范围,盆地充填结束后,由于纵张断裂F3Z切割,下降盘煤系地层埋藏较深,根据上升盘煤层发育分析,预测下降盘应为找煤的可靠远景区。

China is situated at the southeastern part of Eurasian plate, under the Eurasian, Kula-Pacific and Indian plates three directional disequilibrium actions has resulted in formation of the Tancheng-Lujiang fault in the eastern China during MesozoicCenozoic Era, while the Meihe basin is a graben-semigraben coal accumulating basin in the Fushun-Mishan fault zone, a branch of Tancheng-Lujiang fault in Northeast China. The tectonic framework is a result of various stage structural superpositions during the basin evolutionary process, including previous basement structure, syndepositional structure and succeeding reformed structure. From the basin＇s beginning to end, basin marginal faults （F1 and F2） controlled basin deposition and extent, after the basin filled up, because of dissection by the longitudinal tension fault F3Z, downthrown side coal measures is deeply buried, according to hanging wall coal seam development, the downthrown side should be credible prospect area to look for coal.