中上扬子区海相层系流体特征与油气保存条件

Fluid characteristics and hydrocarbon preservation conditions in marine facies strata of middle-upper Yangtze region

摘要: 通过对中上扬子区地层水化学特征、地层水氢氧硫同位素、天然气组成特征、天然气烷烃碳同位素、甲烷氢同位素、天然气轻烃组成特征等的研究,结合油气显示及产出情况将中上扬子区流体特征划分为5大区,即:川中—川西区(Ⅰ)、川北—川东—川南区(Ⅱ)、江汉盆地南部(Ⅲ)、黔东南坳陷区(Ⅳ)和湘鄂西区、黔中及邻区、江汉盆地北部等区(Ⅴ),其对应的油气保存条件逐渐变差。

Abstract: Based on studies of formation water chemical characteristics,H,O and S isotopes in formation water,natural gas composition,C isotope in alkane,H isotope in methane and light hydrocarbon composition in the middle-upper Yangtze region,combined with petroleum shows and productions,the research area was divided into 5 blocks according to fluid characteristics:the middle and western Sichuan Basin(Ⅰ),the northern,eastern and southern Sichuan Basin(Ⅱ),the southern Jianghan Basin(Ⅲ),the depression in the southeast of Guizhou Province(Ⅳ),as well as the west of Hunan and Hubei Pro-vinces,the middle of Guizhou Province,and the northern Jianghan Basin(Ⅴ).Preservation conditions decrease from I to V.