摘要
在岩心及薄片观察鉴定、物性特征分析基础上,重点研究了大牛地气田奥陶系风化壳储层特征及发育控制影响因素。研究表明:储层主要为泥微晶-细粉晶白云岩、岩(膏)溶角砾状白云岩和颗粒白云岩3类;储渗体主要有4种类型:晶间孔隙型、溶蚀孔(洞)型、裂缝-孔洞型以及裂缝型,其中孔隙型储层最为发育,溶蚀孔(洞)型、裂缝-孔洞型储层次之,纯裂缝型储层相对较少;储层孔隙度主要分布范围小于4%,渗透率主要分布范围(0.01~0.32)×10-3μm2,为低孔-低渗致密储层。研究区下古生界奥陶系风化壳储层主要受沉积和古岩溶作用的控制,在奥陶系顶部形成了大量溶蚀孔、洞、缝,形成了碳酸盐岩岩溶储层。
Based on cores and thin sections observation,identification and physical properties analysis,the research on reservoir characteristics and development controlling factors of Ordovician weathering crust in Daniudi gas field has been carried out.The results indicate the reservoirs are mainly of3 classes,the mud microcrystalline powder crystal dolomite class,the rock(cream)dissolved breccia dolomite class and the grain dolostone class.There are mainly four types of storage-permeation bodies,the intergranular pore type,the solution pores type,the cracks-holes type and the cracks type,among which the pore type is the most developed,the dissolution pore(hole)and the crack-hole types followed,while the pure fractured-vuggy reservoir is relatively less.The main distribution range of reservoir porosity is less than4%,the permeability distribution range is(0.01~0.32)×10-3μm2 and it belongs to low porosity low permeability reservoir.The reservoirs from Ordovician weathering crust in the lower Paleozoic are mainly controlled by sedimentary and ancient karstification.On the top of the Ordovician,a large number of karst holes,holes and seams have been formed,and then carbonate karst reservoirs have been formed.
出处
《石油地质与工程》
CAS
2015年第3期1-5,145,共6页
Petroleum Geology and Engineering
基金
国家重大专项"鄂尔多斯盆地大牛地致密低渗气田勘探开发示范工程"(2011ZX05045)资助
关键词
大牛地气田
储层特征
孔隙类型
岩石学特征
奥陶系
风化壳
Daniudi gas field
reservoir characteristics
pore types
petrological characteristics
Ordovician
weathe-ring crust
