Coal Reservoir Laboratory of National CBM Engineering Center,China University of Geosciences (Beijing)

为了研究煤层气系统热流体偶合地质作用机制,对织金、盘县煤系热流体地质特征进行了对比,并从地层热流体活动新的视角分析了黔西煤层气富集成藏地质选择过程。研究表明:织金、盘县均存在两期区域性热流体活动,早期以钙质流体为载体,晚期以硅质流体和少量钙质流体为载体,分别属于地层流体热循环作用和深源高温热流体的差异注入。热流体作用促使煤层气集中高强度生成和运移,产生密集成群管状气孔,与构造应力协同,导致煤体开裂破碎,明显影响煤的孔渗性。煤系地层中相对封闭滞留的热流体环境,是导致煤层气系统高压形成的重要因素之一。黔西北部台隆处于相对封闭滞留区,高温热流体配置条件更有利于煤层气富集成藏。

in order to disuss the coupling geological mechanism of hydrothermal fuid in coalbed methane system,this paper compared the geolgical character ofthe hyrothermal fuid between Zhjin and Panwian in West Guizhou.and analyzed the geological po.ess ofenrichment and accumulaton of coalbed methane from newperspeciveof hydrothermal fud civties in formation.The resuls showe that two stages regional thermal fuid activties happened in the Zhijin and Panxian.In the early stage,the cacium fuid was the carier but it became t iliceou fuid and a small mount of cacun fuid in the laler stage.The fomer was the resut of themal cycling effect of fui in formation and the laterwas caused by the diferental njection of dep- source and high temperature fuid. The hydrothermal fuid inpelld coalbed nethane to generate and migrate at igh intensty aiong with producing dense swarms tubular pores,which were coincident withtfactonic stre.s.Aks a resut.the cal ody was broken and the porosity and permeablity of cal vere affcted obiously. one of the most important factors which lead to high stess in coalbed nethane system was the relatively closed and stranded hydrothermal fuid enironment in coal measure strata.Plafom upise in the nrtheast of Gizhou region was just in such anenvironment:where the high temperature fuid could provide more favorable conditions for the enrichment and accumulation of coalbed methane.

国家科技重大专项资助项目(2011ZX05034)；国家自然科学基金重点资助项目(0730422)；国家自然科学基金面上资助项目(41272175)；