【摘要】 金宝屯盆地是一中生代内陆盆地。含煤地层为上侏罗统协尔苏组,主要由灰绿色、灰色砾岩和砂岩,灰黑色、黑色细砂岩和粉砂岩、泥岩及灰白色中—粗砂岩组成,平均厚110m。区内不同沉积环境,出现在盆地演化的不同阶段和盆地的不同部位。下部砾岩段沉积期以冲积扇环境为主;含煤段沉积期为冲积扇-河流-湖泊环境组合;成煤后演化为曲流河环境;上部砂岩砾岩段沉积期以辫状河沉积为主。聚煤作用发育于盆地中的湖泊分布区,发生于盆地快速沉降之后的整体稳定、缓慢沉降阶段的早期,煤层直接覆于湖相厚层泥岩之上。盆地仅经历了一个快—慢沉降旋回,煤层的形成受控于这种“无振荡聚煤作用”。更多还原

【Abstract】 The Jinbaotun basin is a Mesozoic intracontinental basin, in which coal-bearing strata are represented by the Upper Jurassic Xie’ersu Formation. It, 110 meters thick, is composed of greyish green, grey conglomerate and sandstone, greyish dark and dark fine sandstone, siltstone and mudstone and greyish white medium-coarse sandstone with coalbeds. Different environments of the basin are believed to occur in different phases of the basin evolution and in different places. In the lower part, the stage of deposition of the conglomerate member was mainly marked by the alluvial fan environment and the stage of depostion of the coal-bearing member was marked by the alluvial fan-fluvial-lacustrine environment association, which evolved into a meandering stream environment after coal formation. The stage of deposition of the sandstone-conglomerate member in the upper part mainly witnessed the sedimentation of braided stream deposits. Coal accumulation occurred in lake districts in the basin, in the early stage of the episode of en-masse stable and slow subsidence after the rapid subsidence of the basin. The coal bed directly covers lacustrine thick-bedded mudstone. The basin only experienced a cycle of rapid-slow subsidence, and the formation of the only coal bed was controlled by this "coal accumulation without oscillations".更多还原