歧南断阶带沙一段重力流类型及勘探潜力分析

Gravity flow identification characteristics and exploration potential in Es1 of Qinan Fault step belt

李振鹏 王航 常涛 刘建国 刘斌

中海石油（中国）有限公司天津分公司，天津 300459

Tianjin Branch of CNOOC Ltd., Tianjin 300459, China

以岩心、测井、地震及分析化验资料为基础，对歧南断阶带沙一段重力流沉积形成机制、识别特征及沉积模式进行研究。结果表明：研究区沙一段重力流沉积机制共分为滑动滑塌、泥质碎屑流、砂质碎屑流及浊流4种类型；受断层活动对古地貌的影响，研究区平面上向凹陷中心方向依次发育滑动滑塌沉积、碎屑流沉积及浊流沉积。在此基础上，从重力流沉积发育位置、圈闭条件及储层物性3个方面对4种成因重力流砂体的勘探潜力进行了分析，认为砂质碎屑流成因的湖底扇中扇亚相砂体沉积勘探潜力最大，其次为滑动滑塌成因砂体，浊流成因砂体次之，泥质碎屑流成因的内扇亚相砂体潜力最差。

Formation mechanism, recognition characteristics and depositional model of Es1 Formation in Qinan Fault step belt were studied based on core, well logging, seismic and experimental data. Analysis results show that the mechanism of gravity flow sediments can be divided into four types, which are slide and slump deposits, muddy debris flow, sandy debris flow and turbidity flow deposits. Affected by the influence of fault activity made on the paleogeomorphology, the gravity flow sediments develop slide and slump deposits, debris deposits and turbidity flow deposits successively to the depression center direction. Exploration potentials of four types of sand bodies were analyzed on the basis of comparative studies of sand body location, trap conditions and reservoir physical properties. The results show that the middle fan formed by sandy debris flow has the best exploration potential, followed by the slide and slump deposits, finally the turbidity flow deposits, and the exploration potential of muddy debris flow deposits is the worst.

10.6056/dkyqt201901002