摘要
南海北部深水区中新统钻遇了具有白垩状结构的高孔低渗抱球虫生物碎屑灰岩,孔隙度高达30%,但渗透率小于1 mD。这些沉积岩主要由深水抱球虫组成,含陆源碎屑和黏土矿物,抱球虫体腔孔是高孔隙的主要贡献者,由于各体腔孔独立,抱球虫壳体之间的黏土矿物及其他生物碎屑杂基导致沉积岩整体孔隙连通性差。在北大西洋北海油田发现类似的深水沉积灰岩,是高孔优质储层。对比研究认为,这种深水抱球虫生物碎屑如果经浊流或等深流等改造,可以成为优质储层。关注这一类型的沉积作用,可望为南海深水勘探增加碎屑岩重力流储层以外的新储层类型。
The chalky-textured globigerina hioclastic limestones with high porosity and low permeability were discovered during the drilling of Miocene strata in deep-water area of the northern South China Sea. The porosity is up to 30%, while the permeability is less than 1 mD. The limestones are mainly composed of deep-water globigerina, including terrigenous clastics and clay minerals. The globigerina coelomopores have made a major contribution to high porosity. However, these coelomopores are unconnected, and among them filled with clay minerals and bioclastics, leading to poor pore connectivity in the entire limestone. The similar deep-water limestone is also discovered in North Sea oil field of North Atlantic, and has high quality reservoirs with high porosity. A comparative study suggests that the deep-water globigerina bioclastics can be transformed into high-quality reservoir through turbidity current or contour current. If this sedimentary process being concerned, a new type of reservoir is expected to be detected in deep-water of the South China Sea, besides clastic gravity flow reservoir.
出处
《石油学报》
EI
CAS
CSCD
北大核心
2013年第S02期32-38,共7页
Acta Petrolei Sinica
基金
国家自然科学基金项目(No.91128207)
国家重大科技专项(2011ZX05025-006)
国家重点基础研究发展计划(973)项目(2009CB219400)资助
关键词
南海北部
深水区
白垩
碳酸盐岩储层
勘探新领域
中新统
northern South China Sea
deep-water area
chalk
carbonate reservoir
new exploration fieid
Miocene
