东胜煤田延安组层序地层学特征及煤相演化主控因素分析  

Analysis on Sequence Stratigraphy Characteristics and Main Controlling Factors of Coal Facies Evolution of Yan’an Formation,Dongsheng Coalfield

作　　者：沈阳阳 吕大炜 张之辉 SHEN Yangyang;LYU Dawei;ZHANG Zhihui(College of Earth Science and Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590)

机构地区：[1]山东科技大学地球科学与工程学院,山东青岛266590

出　　处：《中国煤炭地质》2023年第1期1-6,18,共7页Coal Geology of China

基　　金：国家自然科学基金项目“华北东部晚石炭—早二叠世煤系沉积记录对全球低纬度沉积古气候研究的启示”(41972170);国家自然科学基金项目“鄂尔多斯盆地中—下侏罗统延安组煤系沉积记录定量古气候重建”(42102127);国家重点研究计划重点专项“喀斯特型铝土矿形成过程与成矿模式”(2022YFC2903402)。

摘　　要：运用传统沉积学、层序地层学理论知识,通过野外实地观测和钻井资料分析,对东胜地区延安组进行了层序地层划分。识别出两个三级层序(层序Ⅰ、层序Ⅱ),三个沉积体系域(低位体系域、湖侵体系域、高位体系域)。在延安组识别出两种沉积相——曲流河和湖泊三角洲。同时对延安组的煤层进行显微组分定量统计,研究显示研究区煤相主要为潮湿森林沼泽相。研究区构造稳定,煤相的垂向演化主要受湖平面波动的影响,而湖平面的波动受气候约束,显示气候是煤相演化的主要控制因素。Based on the principle of traditional sedimentology and sequence stratigraphy,the sequence stratigraphy of Yan’an Formation in Dongsheng area is divided,through the comprehensive analysis of the field observation and drilling data.Two third-order sequences(sequence Ⅰ and sequence Ⅱ) and three system tracts(lowstand system tracts,extended(lacustrine) system tracts and highstand system tracts)are recognized.Two sedimentary facies,including meandering river and lacustrine delta,were identified in the Yan’an Formation.In addition,the quantitative statistics of maceral were introduced to identify the coal faces as moist forest swamp.The tectonic setting of the Dongsheng area was stable,and the vertical evolution of coal faces was mainly affected by the fluctuation of lake level,which was constrained by climate.Thus,the climate was the main controlling factor of coal faces in the Yan’an Formation.

关 键 词：东胜煤田 延安组 层序地层 显微组分 煤相 

分 类 号：P618.11[天文地球—矿床学]