济阳拗陷砂岩次生孔隙的基本特征及控制因素

针对济阳拗陷下第三系砂岩次生孔隙具有储集岩体类型多、分布层位广和次生孔隙种类丰富的特点 ,利用铸体薄片及地球化学方法 ,分析了次生孔隙发育的基本条件。结果表明 ,控制砂岩次生孔隙发育的主要因素包括 :1处于不同沉积相带的砂岩体 ,次生孔隙发育程度不同 ;2成岩作用强度不同 ,次生孔隙发育程度不同 ;3断裂作用起到输送酸性介质通道的特殊作用 ,并使次生孔隙的形成得到改善 ;4高地温能加快有机质的成熟 ,从而有利于次生孔隙在较浅的深度形成。认为砂岩中的各类易溶物质以及成熟烃源岩中含有丰富的有机质 ,为次生孔隙的形成提供了基本的物质条件。

Fundamental characteristics and its control factors over secondary pores of Eogene system sandstone in Jiyang depression

Based on optical examination of casting thin sections and analyses of geochemistry the characteristics of the secondary pores,which can be made in multiple reservior bodies and distributed in more formations and classified into many types,are studied on Eogene system sandstone in Jiyang depression.The fundamental factors that controled making secondary poresareanalysed.The causesshow asfollows:( 1 ) The developing of secondary proes may be varied in sandstone bodies placed different sedimetary facies;( 2 ) The developing of secondary pores may be varied in different diagentic grade;( 3) The growing of secondary pores can be improved because of faults;( 4 ) The making of secondary pores may be formed in relative shallow depth due to higher geotemperature.The results demonstrate that the both soluble substances of sandstone and abundant organic rock source provided the fundamental materials for making secondary pores.