鄂尔多斯盆地青龙山剖面中寒武统沉积特征及沉积模式  

Sedimentary characteristics and evolution model of the Middle Cambrian in the Qinglongshan Section,Ordos Basin

作　　者：汪涵 吕奇奇[1] 高永亮 霍勇 孙学虎 王林 WANG Han;LYU Qiqi;GAO Yongliang;HUO Yong;SUN Xuehu;WANG Lin(School of Geosciences,Yangtze University,Wuhan,Hubei 430100,China;Research Institute of Exploration and Development,PetroChina Jidong Oilfield Company,Tangshan,Hebei 063004,China;Geological Research Institute,China National Logging Corporation,Xi'an,Shaanxi 710076,China)

机构地区：[1]长江大学地球科学学院,湖北武汉430100 [2]中国石油冀东油田公司勘探开发研究院,河北唐山063004 [3]中国石油集团测井有限公司地质研究院,陕西西安710076

出　　处：《东北石油大学学报》2024年第4期1-15,I0001,共16页Journal of Northeast Petroleum University

基　　金：中国石油天然气股份有限公司科学研究与技术开发项目(2021DJ05);国家科技重大专项(2016ZX05004-001-004)。

摘　　要：根据野外露头观察及薄片鉴定,研究鄂尔多斯盆地青龙山剖面中寒武统的岩相类型和岩相组合特征,分析沉积相类型、特征和剖面相,建立沉积模式。结果表明:青龙山剖面中寒武统发育13种(LF1—LF13)岩相类型,识别8种岩相组合,分别为亮晶鲕粒灰岩和土黄色泥页岩,颗粒支撑砾屑灰岩、亮晶鲕粒灰岩和土黄色泥页岩,泥晶生物屑灰岩和土黄色泥页岩,泥晶鲕粒灰岩和土黄色泥页岩,灰绿色泥页岩和泥晶鲕粒灰岩,条带状灰岩和放射状砾屑灰岩,条带状灰岩和土黄色泥页岩,含球粒粉晶白云岩和土黄色泥页岩。中寒武统发育碳酸盐岩缓坡沉积体系,主要为内缓坡相,包括潮坪、潟湖、滩间海、颗粒滩4种亚相和10种微相。中寒武世,青龙山剖面处于碳酸盐岩缓坡环境,随秦祈海槽向东、北方向发生海侵,受青铜峡—固原断裂的影响,沉积中心向东迁移,沉积相带由潮坪—潟湖向颗粒滩—滩间海转变,出现海退迹象,再次转变为潮坪沉积。该结果为鄂尔多斯盆地古环境恢复提供依据。Through field outcrops observation and thin sections identification,the lithofacies types and lithofacies assemblage characteristics of the Middle Cambrian in the Qinglongshan Section of the Ordos Basin were studied.The types and characteristics of sedimentary facies and section facies were analyzed,and the sedimentary evolution model was established.The study shows that 13(LF1-LF13)lithofacies types and 8 lithofacies assemblages in the Middle Cambrian of the Qinglongshan Section are identified.The lithofacies assemblages include bright crystal oolitic limestone and khaki argillaceous shale,particle-supported gravel limestone,bright crystal oolitic limestone and khaki argillaceous shale,mud crystal bioclastic limestone and khaki argillaceous shale,mud crystal oolitic limestone and khaki argillaceous shale,gray-green argillaceous shale and mud crystal oolitic limestone,banded limestone and radial gravel limestone,banded limestone and khaki argillaceous shale,spherulite-bearing powder crystal dolomite and khaki argillaceous shale.The carbonate gentle slope sedimentary system is developed in the Middle Cambrian,which is mainly inner gentle slope facies.It can be divided into 4 subfacies and 10 microfacies.The subfacies contain tidal flat,lagoon,inter-beach sea and grain beach.In the Middle Cambrian,the Qinglongshan Section was in a carbonate ramp environment.With the eastward and northward transgression of the Qinqi Trough,the sedimentary center migrated eastward under the influence of the Qingtongxia-Guyuan Fault.The sedimentary facies belt changed from tidal flat-lagoon to grain beach-inter shoal sea,and finally changed into tidal flat deposition again due to the signs of sea retreat.The result provides a basis for the restoration in the paleoenvironment in the Ordos Basin.

关 键 词：中寒武统 沉积特征 沉积模式 碳酸盐岩缓坡 青龙山剖面 鄂尔多斯盆地 

分 类 号：TE122.2[石油与天然气工程—油气勘探]