海外河油田东营组自生沸石的发现成因及其地质意义

Discovery and Origin of the Diagenetic Zeolite in Dongying Formation of Haiwaihe Oilfield and its Geological Significance

利用薄片鉴定、油浸法、扫描电镜、电子探针和X-衍射等分析手段,对海外河油田东营组储层顶部的沸石类成岩自生矿物进行了研究。测试结果表明沸石类矿物的种属为辉沸石、片沸石和丝光沸石。他们分布于安山岩岩屑颗粒之中或充填于砂岩粒间孔隙中,其形成与砂岩中的安山岩屑有关。砂岩中自生沸石的形成,使多孔砂岩层转化为致密砂岩层,成为海外河油田的局部盖层,对油藏的形成起到一定的封盖作用。

The diagenetic zeolite in the upper part of Dongying Formation of Haiwaihe Oilfield was studied through rock slice, oil immersion method, scanning electronic microscope, electronic probe and x-ray diffraction.Experimental results indicate that the diagenetic zeolite types include desmine, euzeolite and ptilolite, which distribute inside the volcanic debris or intergranular pore.The diagenetic zeolite formation is related with volcanic debris especially andesite debris.They occupy so much pores of the sandstone that the porous sandstone transformed to tight sandstone.As partial cap rock, these tight zeolite sandstones react on reservoir formation.