泥质岩裂缝油气藏的成藏条件及资源潜力

目前国内外发现的绝大多数泥质岩裂缝油气藏都分布在以暗色泥岩及页岩为主的生油岩中,常富含有机质、钙质或硅质矿物,其有机碳丰度一般为1.0%～20%,有机质类型多样,镜质体反射率多在0.5%～1.3%。构造裂缝、超压微裂缝和成岩收缩缝是主要裂缝成因类型。盖层主要为裂缝不发育的泥岩、膏岩、盐岩等。圈闭类型主要为背斜圈闭及单斜圈闭。由于大量的油气残留在生油岩中,所以,泥质岩裂缝油气藏具有很大的资源潜力。

FORMATION AND POTENTIAL OF FRACTURED MUSTONE RESEVOIRS

Almost all fractured mudstone reservoirs found both in and outside China are distributed in source rocks which are mainly composed of mudstones and shales, abundant in organic matter, calcareous and siliceous minerals. The abundance of organic carbon is 1.0%～20% in common with various types and their vitrinite reflectance is 0.5%～1.3%.There are three main genetic types of fractures which are structural,overpressured and diagenetic contraction ones in the source rocks. The mudstone reservoir caprocks are made up of non fractured mudstones, gypsum and halite rocks. Anticline and monocline are major trap types. The fractured mudstone reservoirs are believed to have great source potential due to a great deal of hydrocarbon remained in the source rocks.