鄂尔多斯侏罗纪盆地形成演化和聚煤规律

鄂尔多斯盆地是在演太平洋构造域和特提斯构造域共同影响下形成的中生代大型内陆拗陷。其演化过程可分为早侏罗世-中侏罗世早期、中侏罗世、晚侏罗世和早白垩世4个阶段，旱侏罗世-中侏罗世早期为重要的聚煤期。聚煤区围绕盆地沉降中心呈环带状展布，煤层层数、厚度及横向变化规律在盆地不同部位表现出不同特点。构造转折期与有利于植物大量繁殖的古气候的有机匹配是控制煤层形成的主要因素。现今盆地范围是后期改造的结果。

STUDY ON THE FORMATION, EVOLUTION AND COAL-ACCUMULATING REGULARITY OF THE JURASSIC ORDOS BASIN

The Ordos Basin, a huge intracontinental depression, influenced by pacific andTethys structural domains, was formed during Mesozoic Era. The evolutionary processes of thedepression can be divided into four epochs: Early Jurassic to early Middle Jurassic, MiddleJurassic, Late Jurassic and Early Cretaceous, of which, Early Jurassic to early Middle Jurassicis an important coal-accumulating period. The coal-accumulating area is distributed ringshapedly around the subsidence centre of the basin, and in which the number, thickness andchange reguldrity of seam rnay vary in different position of the basin. It is showed by tectonicsand sedimentary analyses that the pendt rnatch of tectonic turning peried with palatlimate infavour of formation for plant remins is an essential controlling factor for the forming of coal.The present scope of the basin is the result of after-reforming.