鄂尔多斯盆地靖边气田马五_(1+2)气藏储集单元研究

综合地震、地质、测井等信息,考虑沉积、成岩、地貌、生产动态等多因素,在沟槽识别和致密带研究基础上,通过井间干扰、油层压力变化和试井边界响应分析,按照局部、就近原则对靖边气田马五1+2气藏进行了储集单元划分。共划分出111个储集单元,其中独立型69个,复合型42个。这些储集单元的面积多介于10～50km2之间,单个储集单元的井数一般少于6口。在对气藏储层特征综合认识的基础上,确定流动单元划分思路与流程,并认为关键环节包括古沟槽识别、致密带研究、动静结合确定储集单元等3个方面。储集单元一方面受控于被致密岩相包围的有利成岩相带,宏观上与弱—中等充填泥粉晶白云岩相对应性好;另一方面又受各级古沟槽夹持,在两个一级古沟槽之间往往共生多个储集单元,而这些储集单元边界又严格地受二级或三级沟槽切割控制。

Reservoir Bed Unit of MaJiagou 51+2 Gas Reservoir in Jingbian Gas Field,Ordos Basin

Lower Ordovician Majiagou 51+2 gas reservoir is divided into 111 bed units in which include 69 independent and 42 compound ones. These bed units commonly are 10～50 km2 in extent of area, and the well number of a single bed unit is generally less than 6 wells. Comprehensive recognition of the reservoir bed units are founded on three key aspects, i.e. the identification of paleo-ravines, the research of compact belt and the analysis of combining dynamic and static data. The reservoir bed units are not only under the control of the favorable diagenetic belt that enclosed by dense rocks, but also under the control of different orders of paleo-ravines. Several reservoir bed units commonly coexist between two 1st-order paleo-ravines while the margins of these units are cut by 2nd-order and 3rd-order paleo-ravines.