卫城油田沙四段粘土矿物的研究

卫城油田沙四段碎屑岩储层属于三角洲沉积,通过扫描电镜、X衍射分析表明,储层的粘土矿物主要有绿泥石、伊/蒙混层和伊利石及高岭石。并且粘土矿物随深度的增加呈规律的变化。绿泥石单体主要呈针叶片状,集合体为片状杂乱堆积、花朵状或绒球状,绿泥石以及孔隙充填式存在于颗粒间,减少了孔隙的空间。但同时又抑制了石英的次生加大,对原生孔隙的保存起了积极作用。伊利石粘土矿物单体呈片状、蜂窝状和丝缕状,集合体形态多为碎片状、鳞片状,以孔隙衬垫或孔隙充填物形式存在于颗粒间,导致砂岩中孔隙结构的明显破坏。高岭石单体呈全自形的六角板状晶体,集合体多呈蠕虫状、书本状。

Study on Es4 clay mineral in Weicheng Oilfied

Weicheng Oilfield is an deltaic sedimentary of Es4 clastic rock reservoir which can be determined by the(scanning) mirror and X-ray diffraction to show that the clay mineral reservoir is mainly consists of chlorite,glimmerton/(askanbite) interbed,glimmerton and ancudite.Furthermore,the clay mineral changes as the depth gets greater.The single body of chlorite is in the shape of conifer needle;the aggregate is in the shape of scale aggregate,flower and cloth ball.The(chlorite) exists in the particles which decreases the pore space.In the meantime,it restrains the growth of the quartz which it plays a positiverole in preserving the original pore.The glimmerton clay mineral is in the shape of scale,(honeycomb-like) and filiform;The most of aggregate is in the shape of broken pieces,scale and exists in between the(particles) in the shape of pore liner and pore filling which causes the proe structure in sand body damaged.The single body of ancudite is in the shape of hexagonal crystal and the aggregate is in the shape of worm and book.