鄂尔多斯盆地是印支运动后在滨太平洋构造域和特提斯构造域影响下形成的中生代大型内陆坳陷,现今盆地范围是后期改造的结果.盆地构造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,早侏罗世-中侏罗世早期形成了丰富的煤炭资源.构造运动对聚煤期、聚煤区和煤层形成后的赋存特征均具有重要的控制作用:聚煤期受控于大地构造背景:聚煤区围绕盆地沉降中心呈环带状展布,煤层层数、厚度和横向变化规律在盆地不同部位表现出不同的特点;构造转折期与构造转折部住是控制煤层形成的重要因素.该盆地内主要的控煤构造单元有:西缘褶皱冲断带、天环坳陷、伊陕单斜、渭北断隆和河东断褶带.%Ordos basin, a huge intercontinental depression, influenced by Pacific and Tethys structural domains, was formed during Mesozoic Era. The present scope of the basin is the result of later recreation. The evolutionary processes of the depression can be divided into four epochs: Early Jurassic to the early period of Middle Jurassic, Middle Jurassic, Late Jurassic and Early Cretaceous, of which, Early Jurassic to the early period of Middle Jurassic is an important coal-accumulating period. Tectonics played a vital role in controlling the coal-accumulating period, coal-accumulating area, and the characteristics of the coal. The coal-accumulating period is controlled by the tectonic structure. The coal-accumulating area is distributed ring-shapely around the subsidence centre of the basin,and in which the number, thickness and change regularity of the seam may vary considerably in different positions of the basin. The period and area of tectonic turning are essential controlling factors for the forming of coal. The main tectonic units which are in favor of the coal forming in Ordos basin conclude the western fold thrust zone, Tianhuan depression, Yishan monocline, the Weibei fault uplift, and the Hedong fault-fold zone.
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