断层型圈闭成藏评价新方法及初步应用

NEW METHOD OF RESERVOIR FORMATION EVALUATION IN FAULT TRAP AND ITS PRELIMINARY APPLICATION

目前海拉尔盆地乌尔逊-贝尔凹陷已发现的油藏几乎都与断层相关，据此将油藏分为4大类10小类。通过对断层相关型油气藏系统统计和研究发现，断层油气藏成藏主要受断层垂向断距（L）、储层砂岩视厚度（R）和盖层泥岩观厚度（M）3个因素控制。3个因素之间的相对大小关系决定了1个断层圈闭能否聚集油气，据此提出断层相关型圈闭三元耦合控藏评价方法，分析了6种砂泥对接模式下断层相关型圈闭成藏的差异，认为当M〉L、M〉R时1个断层圈闭成藏条件最好，反之圈闭成藏条件较差。通过对乌尔逊-贝尔凹陷南屯组二段142个断层圈闭的储层砂岩视厚度、盖层泥岩视厚度和断层垂向断距统计分析，应用三元耦合控藏模式对断层型圈闭进行了初步含油气性评价，提交有利圈闭10个，为研究区下步勘探工作提供了理论依据和勘探方向。

At present, almost all the discovered oil reservoirs are related to the faults in Wu＇ erxun-Bei＇ er Sag of Haila＇ er Basin. According to this, these oil reservoirs are divided into 4 groups and 10 sub-groups. By means of the statistics and study of the related-type petroleum system to above faults, the discovered formation of fault petroleum reservoir is mainly controlled by the following 3 factors ： vertical fault lag （ L ） , the apparent thickness of reservoir sandstone （R） and the apparent thickness of regional caprock mudstone （M）. It is the corresponding size relation of the above 3 factors that determines whether petroleum can be gathered in or not in a fault trap. According to this, the evaluating method of reservoir formation called ternary coupling controlling trap is presented for fault-related traps, and then the differential of the above reservoir formation is analyzed for 6 kinds of sandstone ＆ mudstone clocking modes. When M 〉 L and M 〉 R, the forming conditions for this kind of fault reservoir are thought to be best; on the contrary, the conditions are much worse. Through the statistics analysis of above R, M and L for 142 fault traps in No. 2 Member of Nantun Formation in Wu＇ erxun-Bei＇ er Sag, and furthermore with the help of the reservoir forming modes by ternary coupling, the preliminary petroleum-bearing property has been established and then 10 favorite traps have been figured out and taken over, thus the theoretical foundation and exploration direction are provided for the further study in the region.