东海盆地某凹陷P井区平湖组沉积微相及沉积模式  

MICROFACIES DISTRIBUTION AND SEDIMENTARY MODEL OF PINGHU FORMATION IN P WELL AREA,EAST CHINA SEA BASIN

作　　者：张志垚 张昌民[1] 侯国伟 徐清海 冯文杰[1] 陈哲[1] ZHANG Zhi-yao;ZHANG Chang-min;HOU Guo-wei;XU Qing-hai;FENG Wen-jie;CHEN Zhe(School of Geosciences,Yangtze University,Wuhan 430100,China;Shanghai Branch,CNOOC Limited,Shanghai 200335,China)

机构地区：[1]长江大学地球科学学院,湖北武汉430100 [2]中海石油(中国)有限公司上海分公司,上海200335

出　　处：《地质与资源》2020年第2期142-151,160,共11页Geology and Resources

基　　金：国家“十三五”重大科技专项“深层优势储层形成条件及地质预测技术”(编号2016ZX05027-02-007).

摘　　要：以东海陆架盆地某凹陷西部斜坡带P井区7口井的岩心详细观察与描述资料为基础,综合利用测井、分析化验数据及地震等资料,研究平湖组沉积微相及沉积模式.结果表明:P井区平湖组发育一套海陆过渡沉积体系,主要为潮汐影响的三角洲-潮坪相沉积,沉积亚相主要包括三角洲前缘、前三角洲和潮间带.进一步识别出了水下分流河道、河口沙坝、分流间湾、潮汐水道等7种沉积微相.同生断层对沉积微相平面分布影响明显.断距较小时,随着物源与断层走向夹角的增大,水下分流河道会出现改道等现象;断距较大时,水下分流河道沉积物仅在同生断层上盘低部位沉积,向盆地中心推进有限.在沉积体系分析的基础上,建立了研究区潮汐影响三角洲前缘的沉积模式.Based on the detailed observation and description of cores from 7 wells in P well area in the East China Sea shelf basin,the sedimentary microfacies types and sedimentary models of Pinghu Formation are studied comprehensively with logging,laboratory and seismic data.The results show that the Pinghu Formation in the study area develops a set of transitional sedimentary system,dominated by tidal delta-tidal flat deposits.The sedimentary subfacies mainly include delta front,prodelta and intertidal zone.Seven sedimentary microfacies,such as underwater distributary channel,mouth bar,interdistributary and tidal channel,are further identified.The distribution of sedimentary microfacies is obviously affected by the syngenetic fault.Where the fault throw is small,the underwater distributary channel sediments will be diverted with the increase of the angle between the provenance and the strike of fault.While at the places with large fault throw,the sediments will be deposited only in the lower part of the hanging wall of the contemporaneous fault,with limited advance to the center of the basin.Based on the analysis of sedimentary system,the sedimentary model of tidal delta front in the study area is established.

关 键 词：平湖组 沉积微相 沉积模式 东海盆地 

分 类 号：P618.130.2[天文地球—矿床学]