不同运移方向下断盖配置对油气运移作用的差异性

为了研究含油气盆地不同运移方向下油气分布规律,在断盖配置类型及其确定方法研究的基础上,根据断盖配置类型与油气垂向和侧向运移方向、距离及所需条件之间关系,对不同运移方向下断盖配置对油气运移作用的差异性进行了对比研究。其差异性主要有3个方面:(1)对油气运移作用方式的差异性,断盖配置封闭对油气垂向运移起变径输导作用,而对油气侧向运移起继续输导作用;断盖配置不封闭对油气垂向运移起继续输导作用,而对油气侧向运移起变径输导作用;(2)对油气运移距离作用的差异性,断盖配置封闭使油气垂向运移至盖层之下,而使油气侧向运移超过输导断裂;断盖配置不封闭使油气垂向运移至盖层之上,而使油气侧向运移至输导断裂处;(3)阻止油气运移所需条件的差异性,油气垂向运移欲通过断盖配置运移动力相对较强,所需阻止油气运移所需的最小断接厚度相对较大,而油气侧向运移欲通过断盖配置运移动力相对较弱,阻止油气运移所需封油气最小断接厚度相对较小。研究成果对指导含油气盆地源内和源外断裂发育区油气勘探具有重要意义。

Differential of the hydrocarbon migration action by the fault-caprock match in different migration directions

In order to study the distribution law of the oil and gas under different migration directions in hydrocarbon-bearing basins, based on the research of the fault-caprock configuration types and their determining methods, by means of the relationships between the configuration types and oil-gas vertical-lateral migration directions, distance and required conditions, the contrast studies were conducted for the differentials of the fault-caprock configuration types acting on the oil and gas migration actions. The differentials are mainly showed in following 3 aspects:①For the differential in the hydrocarbon migration way, the fault-caprock configuration sealing action plays a role of changing the path and transporting for the vertical migration, while for the lateral migration, the role is continuously transporting;the non-sealing of the fault-caprock configuration plays a role of continuous transporting for the vertical migration, while for the lateral migration, the role is changing the path.② For the difference in the migration distance of the oil and gas, the configuration sealing makes the vertical migration to the bottom of the caprock, while for the lateral migration, the migration distance is over the transporting fault;the non-sealing of the fault-caprock configuration makes the vertical migration to the top of the caprock, while for the lateral migration, the migration distance is only up to the transporting fault.③The difference in the required conditions of stopping the hydrocarbon migration, the vertical migration power of the oil and gas needed through the fault cap configuration/allocation should be relatively stronger, and the minimal connected thickness required to prevent the oil and gas migration is relatively larger, while for the lateral migration, the power is relatively weaker, so as the minimal connected thickness. The study results possess important significances for guiding the petroleum exploration of the fault well-developed regions both in the source and outside the source of the hydrocarbon-bearing basin.