塔里木盆地塔北隆起凝析气藏的分布规律

DISTRIBUTION LAW OF THE CONDENSATE GAS RESERVOIRS IN TABEI UPLIFT

塔北隆起凝析油气资源十分丰富，探明储量占全盆地的７０％以上。天然气中凝析油含量高。凝析气藏在成因上分海相和陆相两类，各有自己的分布规律。塔北隆起被轮台断隆顶部“一分为二”，形成南、北两个海、陆相凝析油气系统。陆相中新生界凝析气藏的分布受两组南掉正断层控制；海相凝析气藏的分布受寒武、奥陶系断垒潜山及其上的中生界披覆背斜、断背斜控制。两类凝析气藏都属“下生上储”式“次生”油气藏，气源断层的存在至关重要。沿断裂带寻找凝析气藏是一个重要的勘探方向。

Tabei Uplift is quite abundant in condensate and gas resources,its proved reserves accounting for more than 70 percent of the total in the basin.The condensate content in natural gas is high.In genesis,the condensate gas reservoirs can be divided into two types as marine facies and continental facies ones,each having its distribution law.The top of Tabei Uplift was divided into two parts by Luntai fault rise to form two condensate gas systems belonging to marine facies and continental facies in its south and north respectively.The distribution of the continental facies condensate gas reservoirs in Mesozoic Cenozoic is controlled by two groups of normal faults throwing towards the south and that of the marine facies ones by the fault horst burid hills of Cambrian Ordovician and the drape anticlines and fault anticlines of Mesozoic upon them.The two types of condensate gas reservoirs belong to the “Downgenerated Up stored”secondary reservoirs,the existence of gas source faults being very important.Therefore,it is a significant exploration trend to search for the condensate gas reservoirs along the fault belts.