卡姆斯特煤田侏罗系八道湾组地层层序及聚煤特征

Stratigraphic sequence of the Jurassic Badaowan Formation and coal-forming characteristics of the Kamst coalfieldi

综合利用卡姆斯特煤田钻孔测井、野外露头及古生物化石等资料,应用经典层序地层学基本理论和方法,对卡姆斯特煤田八道湾组进行了层序地层划分,共识别出SQ1和SQ2两个三级层序,并根据地层叠置样式、沉积旋回特征细分为6个体系域。通过沉积基础图件、沉积环境的分析明确了研究区八道湾组沉积演化主要受古地形起伏、古气候条件等古地理因素的综合影响。确定研究区内目的层段主要在高位和低位时期聚煤,湖侵时期不利于聚煤。通过详细研究卡姆斯特煤田八道湾组的沉积环境和聚煤特征,为今后寻找和开发卡姆斯特地区煤炭资源提供地质依据。

Based on drilling,logging,field outcrop and fossil data obtained in the Kamst coalfield and using the basic theory and method of classic sequence stratigraphy,the authors divided the sequence stratigraphy of the Badaowan Formation in this coalfield,and identified two 3rd-order sequences of SQ1 and SQ2.According to the style of stratigraphic superposition and cycle of sedimentation,the authors further subdivided them into six system tracts.On the basis of the basic deposition maps and the analysis of sedimentary environment,the authors have revealed that the sedimentary evolution characteristics of the Badaowan Formation were mainly affected by the difference in land forms and palaeoclimate.It is found that the coal-formation of the purpose layers occurred during the period of lowstand and highstand systems tracts,but lacustrine transgression was not conducive to coal accumulation.Through a detailed study of sedimentary characteristics and coal accumulation of the Badaowan Formation in the Kamst coalfield,this paper provides basic data for further coal exploration.