鄂尔多斯盆地白豹地区延长组中段沉积特征与沉积模式

SEDIMENTARY CHARACTERISTICS AND MODE OF THE YANCHANG FORMATION MIDSECTION OF BAIBAO AREA IN THE ORDOS BASIN

郭德运 郭艳琴 李文厚 张惠 李克永

Guo Deyun Guo Yanqin Li Wenhou Zhang Hui Li Keyong

西北大学, 地质学系, 西安, 710069 2. 西安石油大学, 油气资源学院, 西安, 710065 3. 延安大学, 能源与环境工程学院, 陕西, 延安, 716000

Department of Geology, Northwest University, Xi'an, Shaanxi 710069, China 2. Institute of Oil and Gas Resources, Xi'an Shiyou University, Xi'an, Shaanxi 710065, China 3. Institute of Energy Resources and Environmental Engineering, Yan'an University, Yan'an, Shaanxi 716000, China

通过对鄂尔多斯盆地白豹地区延长组中段长4+5—长3油层组大量钻井岩心和测井资料综合研究,以及沉积体系、沉积相特征的描述,识别出其沉积特征,划分了沉积相类型。白豹地区长4+5—长3为湖泊—三角洲沉积体系,其中三角洲前缘沉积主要发育在研究区东北部,浅湖沉积主要发育在研究区西南部且规模较小。研究区三角洲主要为浅水台地型三角洲,缺乏完整的进积序列,在三角洲前缘沉积中,由于水下分流河道的迁移摆动,水下分流河道砂体与分流间湾泥质沉积在单井剖面上呈交替出现、反复叠置的特征序列,或者是水下分流河道砂体直接位于湖相泥岩之上的沉积序列。

To identify the sedimentary characteristic and divide the sedimentary type of Chang 4+5 and Chang 3 Member of Yanchang Formation midsection of Baibao area in the Ordos Basin,the main me-hods used include the core observation,well logging data analyses and description of deposition system and sedimentary facies.It is found that the deposition system is lacustrine-delta in which the delta front develop in the northeast of the studying region and the shallow-lake deposits develop in southwest which scale is small.The shallow water platform delta is develop chiefly in region of studying and the completion prograded sequence is absent.Owing to the subaquatic distributary channels diversion,the sand of subaquatic distributary channels and the mudstone of interchannel are intimate associated and repeated overriding or the sand of subaquatic distributary channels is located on the mudstone of lacustrine facies directly in individual well section.

国家科技重大专项专题(2008ZX05005-004-08HZ);陕西省自然科学基础研究计划(2009JM5002)资助

https://doi.org/10.11781/sysydz201003252