第38卷第2期 2017年4月
文章编号：10013873(2017)020137-07
新疆石油地质
XINJIANG PETROLEUM GEOLOGY DOI:10.7657/XJPG20170203
Vol. 38,No.2 Apr. 2017
廊固凹陷大兴断裂带沙四一沙三段近岸水下扇沉积特征
梁官忠"2,刘龙松",张峰",纪友亮"吕亚辉”，李彦国？
（1.中国石油大学地球科学学院油气资源与探测国家重点实验室，北京102249；2中国石油华北油田分公司，河北任丘062552）
摘要：廊圈四陷大兴断裂带相继发现兴8、兴9等砾岩油气藏，油气资源丰富，且多数油气藏处于近岸水下扇扇中辨状水道微相，因此对大兴断裂带近岸水下扇的沉积特征进行研究显得尤为重要。综合前人研究成果和廊固凹陷最近获取的岩心、地震、测并等资料，对近岸水下扇进行了沉积微相特征的识别及沉积微相类型的划分，总结了近岸水下扇分市特征，并分别建立了碎周流及泥石流近岸水下扇沉积模式。醇肩流近岸水下扇在旧州地区发育，扇体表现为厚层碍岩与泥岩的突变接触，沉积物主要是颗粒支撑碳岩，杂基含量很少；面泥石流近岸水下扇在围安地区发育，局体几乎无水道发育，沉积物主要为杂基支撑碳岩，杂基主要为泥质。醇屑流近岸水下离识别出扇根主水道、扇根水道间、扇中辨状水道、扇中辨状水道间、扇端席状砂和扇端泥6种沉积微相，其中扇中辨状水道微相是扇中甚基至整个碎屑流近岸水下
扇的主体，扇端亚相相对不发育。近岸水下扇整体上沿大兴断层呈近北东一南西阅展布，在沙三下亚段最为发育。关键词：激海湾盘地；廊围凹陷；大兴断裂带；沙河衡组；近岸水下；沉积微相
中图分类号：TE122.221
文献标识码：A
SedimentaryCharacteristics ofNearshore SubaqueousFans of Sha-4—Sha-3Member of
Shahejie Formation in Daxing Fault Zone of Langgu Sag
LIANG Guanzhong,LIU Longsong”,ZHANG Feng,JI Youliang,LYU Yahui?,LI Yanguo
(1.State Key Laboratory of Petroleum Resources and Prospecting, School of Geosciences, China University of Petroleum, Beijing 102249
China; 2.Huabei Oilfield Company, PetroChina, Renqiu, Hebei 062552, China)
Abstract: Conglomerate reservoirs with abundant oil and gas resources have been found in Daxing fault zone successively such as Xing 8 and Xing 9 etc. Most of these reservoirs are mid-fan braided channel of nearshore subaqueous fans, Therefore, it is very important to study the sedimentary characteristics of the nearshore subaqueous fans, Based on the previous research results and the latest core , seismic, well logging and other data obtained in the sag, the sedimentary microfacies are identified and classified in this paper, The vertical and horizon-tal distributions of the nearshore subaqueous fans are summarized and the depositional models of them are established for debris flow and mud flow, respetively, The debris flow nearshore subaqueous fan is developed in Jiuzhou area with an abrupt contact between the thick conglomerate and mudstone in the fan body. The sediments are mainly composed of particle-supporting conglomerates with little matrix Whereas, the mud flow nearshore subaqueous fan is found in Gu'an area. Few channel exists in the fan and the sediments are mainly matrix-supporting conglomerates with the matrix dominated by mud. The debris flow nearshore subaqueous fan can be classified into six sedimen-tary microfacies such as main channel of root fan, interchannel of root fan, braided channel in midfan, braided interchannel in midfan, sheet sand in endfan and mud in endfan, among which the braided channel in midfan is the main body of the midfan and even the debris flow nearshore subaqueous fans, The endfan is relatively undeveloped, The nearshore subaqueous fans are in near NE trending distribution along Daxing fault zone with the lower third member of Shahejie formation being the most developed.
Keywords: Bohai Bay basin; Langgu sag; Daxing fault zone; Shahejie formation; nearshore subaqueous fan; sedimentary microfacies
近岸水下扇指发育于断陷盆地陡坡带断层下降盘根部、邻近物源进人水体快速堆积、与深湖暗色泥岩互层、以重力流流动机制为主的扇形粗碎屑岩体-2，主要形成于陆相断陷湖盆的扩张期，随着湖水范围的扩大，扇体也不断后退，并始终沿湖盆边缘紧邻山麓部位分布-"。不同学者对近岸水下扇沉积相的划分不同，但均认识到其具有三分的沉积特征，如
收稿日期：2016-09-06
修订日期：2016-12-20
基金项目：中国石油科技重大专项（2014E-3504）
文献[8]将近岸水下扇划分为内扇、中扇和外扇3个亚相;文献[9]将近岸水下扇划分为扇根、扇中和扇缘 3个亚相。廊固凹陷大兴断裂带渐新统沙河街组沙四段上部和沙三段下部碳酸盐质砂砾岩广泛发育，上部通常称其为“砂砾岩体”，属于近岸水下扇沉积。
些学者对该地区近岸水下扇沉积也做了相关研究：文献[2]明确本区近岸水下扇是分布在凹陷陡坡带断层
作者简介：梁官患（1964-），男，重庆忠县人，高级T.程师，油田开发，（Tel)15831722308（E-mail)wty-L.CI@petrochina.com.rn
通讯作者：刘龙松（1991-），男，江苏连云港人，硕士研究生，沉积储层，（Tel)15201206112(E-mail)457029133@q-com 万方数据