川东北飞仙关组白云岩成因及其次生孔隙  

Genesis and secondary pores of dolomite from Triassic Feixianguan Formation in the northeast of Sichuan Province

作　　者：黄勇[1] 魏志红[1] 邓金花[1] 刘若冰[1] 陈再学 

机构地区：[1]中国石化勘探南方分公司研究院,成都610041 [2]中国石油川庆物探公司国际部,成都610213

出　　处：《成都理工大学学报（自然科学版）》2011年第3期263-270,共8页Journal of Chengdu University of Technology: Science & Technology Edition

摘　　要：白云岩以其次生晶间孔隙发育、易于形成高孔高渗优质油气储层为特征,长期以来受到地质学界的高度重视。早期白云石晶体自形程度及晶间孔隙的发育程度除受白云石化成岩流体的影响外,还受原岩储渗性能的控制。川东北宣汉-达县地区飞仙关组白云岩主要存在渗透回流白云石化、混合水白云石化和埋藏白云石化3种成因模式和至少3期次云化。白云岩化并未直接改善储层物性,不是形成优质储层的主要原因,只是形成优质储层的前提;多期次强烈的溶蚀作用及构造碎裂化作用才是形成优质储层的主控因素。大量次生孔隙主要发育在白云岩化之后。台缘暴露浅滩有利于混合水白云石化和大套层状优质白云岩储层的发育。The dolomites are characterized by the developed secondary intercrystalline pores and easily form qualified reservoirs with high permeability and porosity,and thus are emphasized by geological academic circles for a long time.The idiomorphic degrees of dolomite crystals and the developing degrees of intercyrstalline pores are controlled by accumulating and permeable properties of the original rocks in addition to fluids leading to dolomitization.There exist three genetic models of dolomitization,such as the permeating-flowing-back dolomitization,mixed water dolomitization and burying Dolomitization and at least three times secondary dolomitization for dolomiltes of the Triassic Feixianguan Formation in Xuanhan-Daxuan County in the northeast of Sichuan Province.The dolomitization of dolomites of the Triassic Feixianguan Formation in tje northeast of Sichuan Province does not play the role of improving the geophysical properties of reservoirs and it is not the main reason to form qualified reservoirs but just a premise.Intense dissolution and structural fragmentation of many times are the main controlling factors to form qualified reservoirs and lots of secondary pores developed after dolomitization.The shallow shoals on the platform edge are favorable to undertake mixed water domlomitization and to develop a great set of qualified stratified dolomites reservoirs.

关 键 词：川东北 飞仙关组 白云岩成因 白云石(岩)化 次生孔隙 台缘 

分 类 号：P588.245[天文地球—岩石学]