沁水盆地中北部石炭–二叠纪煤系构造演化特征

Characteristics of tectonic evolution of Carboniferous-Permian coal measures in the north-central Qinshui basin

  • 摘要: 沁水盆地煤及煤层气开发主要集中在盆地两翼及南部转折端,而对盆地中北部煤系能源矿产及构造演化问题略显不足。通过还原聚煤期古构造和沉积环境,结合构造应力场和沉降史恢复等手段,综合分析沁水盆地中北部晚古生代煤系形成过程及多期构造运动对煤系矿产赋存的影响。认为:研究区石炭-二叠聚煤期以北东向沉积坳陷控制了现今盆地构造格局,整体沉积环境由海陆过渡相向陆相过渡;印支期,盆地接受快速沉降,在深成变质作用下,形成煤系气;燕山期,盆地遭到挤压破坏,北东向主体向斜形成,煤系抬升,同时受岩浆热作用,煤化程度提高,向斜两翼煤及煤系气遭到剥蚀和散逸;喜马拉雅期,盆地遭拉张作用叠加破坏,西北部发育大型裂陷和大量正断层,煤系气发生部分逸散,主要富集在研究区中东部。

     

    Abstract: By restoring the paleo-tectonic and sedimentary environment of coal accumulation period, combining with the tectonic stress field and subsidence history, the formation process of Late Paleozoic coal measures in the North-central Qinshui basin and the influence of multi-stage tectonic movement on the occurrence of coal measures minerals were comprehensively analyzed. It is considered that during the C-P coal-accumulating period, the NE-trending sedimentary depression controlled the present tectonic framework of the basin. During Indosinian period, the basin underwent rapid subsidence and formed coal measures gas under the action of deep metamorphism. During Yanshanian period, the basin was destroyed by compression, the NE-trending main syncline formed, and the coal measures strata were uplifted. At the same time, due to magmatic heat, the degree of coalification increased, and the coal and coal measures gas on both sides of syncline were dissipated due to denudation. During Himalayan period, the basin was destroyed by the superimposition of tension. Large-scale rifts and a large number of normal faults developed in the northwest of the basin. Coal measures gas was partially evaporated and mainly enriched in the middle and eastern part of the study area.

     

/

返回文章
返回