青海木里煤田天然气水合物稳定带研究  

Study of the gas hydrate stability zone in Muri coalfield,Qinghai province,China

作　　者：曹代勇[1] 李靖[1] 王丹[1] 豆旭谦[1] 

机构地区：[1]中国矿业大学(北京)地球科学与测绘工程学院,北京100083

出　　处：《中国矿业大学学报》2013年第1期76-82,共7页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(40872105);高等学校博士学科点专项科研基金项目(20110023110003);中央高校基本科研业务费专项资金项目(2010YD11)

摘　　要：天然气水合物稳定带是天然气水合物成藏的必要条件,气体组分、地温梯度、多年冻土层厚度是影响稳定带的主要因素.本文以青海木里煤田钻探得到的天然气水合物实物样品的气体组分为依据,利用Sloan的天然气水合物相平衡程序(CSMHYD),计算得到该区天然气水合物温压相平衡曲线;通过对煤田钻孔简易测温数据的处理,获得冻土层厚度和冻土层下地温梯度等重要数据.基于上述基础数据,提出利用计算机编程模拟计算单孔天然气水合物稳定带参数的方法,根据单孔数据首次编制获得木里煤田天然气水合物稳定带底界埋深等值线图.研究结果表明:木里煤田85个钻孔的天然气水合物稳定带厚度均值达1 000m,显示本区具有天然气水合物赋存的广阔空间;稳定带底界埋深等值线展示了水合物温压平衡区间的平面分布特征,底界埋深超过1 500m的聚乎更矿区南部、哆嗦公马矿区中部和雪霍立矿区东部,是天然气水合物赋存的有利区域.The gas hydrates stability zone （GHSZ） is the essential condition of gas hydrate ac- cumulation,which is controlled by 3 main factors including gas components, geothermal gradient and permafrost thickness. Based on the gas components of drilling hydrate samples in Muri coalfield of Qinghai province, the temperature-pressure phase equilibrium curve of gas hydrate was calculated by using Sloan^s CSMHYD program. Through processing temperature data of coalfield borehole,some important data such as permafrost thickness and geothermal gradient and so on were obtained. The computer program simulation method in accordance with the a- bove data was advanced to calculate GHSZ parameters of single borehole, and the GHSZ bot- tom depth isogram was drawn, for the first time,in the light of boreholes data in Muri coalfield. The results indicated that the average thickness of GHSZ of 85 boreholes in Muri coalfield a- mounted to 1 000 m, displayed a very broad space of gas hydrate occurrence. GHSZ bottom depth contours demonstrated the regional distribution characteristics of temperaturepressure phase equilibrium interval, 3 favorable areas of gas hydrate occurrence, where GHSZ bottom buried deep 〉1 500 m,are the southern part of Juhugeng mining area,the middle part of Duosuogongma mining area and the eastern part of Xuehuoli mining area.

关 键 词：天然气水合物 稳定带 多年冻土带 木里煤田 

分 类 号：P618.13[天文地球—矿床学]