碳酸盐地层在华北地区分布很广,是本地区重要的勘探目的层之一.碳酸盐地层主要指石灰岩和白云岩地层,华北地区的奥陶系寒武系地层主要由石灰岩组成,震旦系地层则主要由白云岩组成。由于石灰岩、白云岩大多岩性致密,原生粒间孔隙极小,一般不具有渗透性,且电阻率很高,其所以能贮藏油气,主要因为其中往往有许多次生孔隙,如裂缝和溶洞。用 Carbonate strata are widely distributed in North China and are one of the most important exploration targets in this region.The carbonate strata mainly refer to limestone and dolomite strata, and the Ordovician Cambrian strata in North China are mainly composed of limestone The Dan Formation is mainly composed of dolomite. Because limestone and dolomite are mostly lithologic and dense, the pores between primary particles are extremely small, generally impermeable and have high resistivity. Therefore, they are able to store hydrocarbons mainly because of the secondary pores, such as fractures and caves. use