摘要
南堡凹陷西南端奥陶系碳酸盐岩潜山具有非均质性强、岩溶储层控制因素复杂等特征,弄清其岩溶发育模式对油田勘探开发有重要意义。应用岩心、成像测井、薄片和地震等资料对潜山储层特征进行研究,认为该区域属于受断裂和岩性控制的岩溶储层,并非典型的风化壳型,岩性主要为泥-细晶白云岩,其基质孔隙物性较差,储集空间以裂缝和小型溶蚀孔洞为主,裂缝主要受古近系和新近系两次构造运动影响,一方面形成了大量的断裂系统,另一方面断裂沟通了地表水对储集空间进行充填。裂缝发育程度与岩性密切相关,粉-细晶白云岩层段孔洞缝密度相对泥晶白云岩层段更发育,裂缝开度更大,经充填作用改造后,仍见较多未充填或半充填的裂缝,以及沿裂缝溶蚀扩大的孔洞。结合钻井资料预测了该类岩性储层的纵向及平面分布范围,指明研究区勘探开发的潜力。
The Ordovician carbonate buried-hill in the southwest of Nanpu sag has been characterized by strong heterogeneity and complex control factors of karst reservoirs.In this paper, the research is carried out for the characteristics of buried-hill reservoirs by using core, imaging logging, thin section and seismic data.Through research, it is considered that the buried-hill reservoir are not typical weathering crust type and are controlled by faults and lithology.The lithology of buried-hill reservoir is mainly composed of micrite-aplite dolomite with poor matrix porosity and small fractures in the reservoir space.Based on the analysis of regional tectonic activity, the formation of fracture system is mainly influenced by two tectonic movements of Neogene and Paleogene.On the one hand, tectonic movements create a large number of fault systems, but on the other hand, the faults connect the surface water to filling the reservoir space.At the same time, combined with core and thin section data, the development degree of fractures in the study area is also closely related to lithology.The density and opening degree of fractures in the powder-aplite dolomite layer is higher than micrite dolomite layer.After filling transformation, unfilled or semi-filled fractures and voids along the fracture dissolution are still visible.The results designate potential for further exploration and development in the research area.
作者
张汶
杜春晓
周连德
张国坤
吕世聪
Zhang Wen;Du Chunxiao;Zhou Liande;Zhang Guokun;Lü Shicong(Tianjin Branch of CNOOC Limited,Tianjin,300459,China)
出处
《天然气与石油》
2019年第5期55-60,共6页
Natural Gas and Oil
基金
“十三五”国家科技重大专项“渤海油田高效开发示范工程”(2016 ZX 05058)
关键词
南堡凹陷
奥陶系
碳酸盐岩潜山
储层特征
岩溶模式
Nanpu sag
Ordovician
Carbonate buried-hill
Reservoir characteristics
Karst model
