滨里海盆地MT油田盐上层储层微观孔隙结构分析

为对哈萨克斯坦滨里海盆地MT油田盐上层储层微观特征进行深入研究,开展了岩心手标本的观察及对研究区200余块样品的薄片分析,认为MT油田储层为陆源碎屑岩,主要为岩屑长石砂岩及次岩屑长石砂岩,颗粒分选中等-差,磨圆较差,具有成分、结构成熟度低的特点,填隙物主要为粘土杂基和钙质胶结物;研究区储层成岩作用主要为压实作用、胶结作用、交代作用及溶蚀作用,以刚性颗粒表面微裂纹、塑性颗粒变形、钙质胶结、石英次生加大、方解石交代碎屑组分、溶蚀孔隙为典型特征.储层发育粒间孔、粒内孔及裂缝孔隙,以原生粒间孔为主.利用Axio Vision4.0系统进一步进行研究区储层的孔隙结构特征研究,将储层孔隙结构划分为4类,并对每类孔隙结构特征进行了分析.

Micro-pore Structure of Upper Salt Reservoir of MT Oilfield in Marginal Caspian Basin,Kazakhstan

In order to study the microscopic reservoir of MT oilfield in Marginal Caspian Basin,Kazakhstan,weanalyzed the drill core and about 200 core wafers. After the analysis about the thin sections,the author thought thatthe compositional maturity and the textural maturity of detrital component in this area are low,and the interstitialmaterials of detrital component are clay matrix material and carbonate cement. And during the observation of thinsections,the lithology in this area is lithic feldspathic and sub-lithic feldspathic. The characteristics of reservoir is＂feldspar north than south and quartz against＂. There are many kinds of diagenesis,such as compaction,cementation,metasomasis,dissolution and denudation. The brittle micro- cracks on the surface of rigid debrisparticles,deformity of ductile grain,carbonate cement,secondary origin quartz,carbonate alternation and corrosionare the common appearances. Using the Axio Vision 4.0 system,we analyzed the characteristics of pore structure inthis work area,classified the pore structure into four kinds,and evaluated the entire four kinds of the pore structure.