天然气水合物分解对井筒周围土层变形的影响  

Deformation of Soil Around the Wellbore Caused by Gas Hydrate Dissociation

作　　者：王晶 张旭辉[1,2] 鲁晓兵 梁前勇[3] 石要红 

机构地区：[1]中国科学院大学,北京100049 [2]中国科学院力学研究所,北京100190 [3]广州海洋地质调查局,广东广州510075

出　　处：《水利与建筑工程学报》2017年第6期48-51,152,共5页Journal of Water Resources and Architectural Engineering

基　　金：国家自然科学基金项目(51639008);中国地质调查局项目(DD20160217-1-1-1);中石油-中科院高端战略联盟计划项目(2015A-4813)

摘　　要：通过运用FLAC3D软件建立三维土体模型,采用具有塑性流动特性的摩尔库仑模型并参考我国近海海域地形和地质参数,分析水合物分解后的井筒周围土体变形,重点讨论天然气水合物分解范围、土层倾角、井筒与土体间的连接方式等因素对土体变形的影响,对深水天然气水合物的开采土体稳定性和安全性进行评估。结果表明:水合物分解范围对土体变形影响最大,水合物分解范围越大,储层的沉降越大;当分解范围超过某临界值时,井筒周围土体发生破坏。这些结论可为深水水合物开采及勘探时的井筒安全评估提供参考。Stratum deformation around wellbore due to GH dissociation was numerically simulated by using FLAC3 D to develop a three-dimensional model of the soil and the model mohr-coulomb which has the plastic flow characteristics,referring as the offshore topographical and geological parameters in China. The effects of GH dissociation range,stratum slope and the connection states between wellbore and stratum on the stratum deformation were mainly investigated to assess the stability and safety of the soil. The results show that the effect of dissociation scope is the greatest. If the dissociation scope exceeds a critical value,the soil surrounding the wellbore can be failure. These results can be taken as the references to the safety assessments on the exploration and recovery of marine GH.

关 键 词：天然气水合物 井筒 分解范围 土体变形 安全评估 

分 类 号：P75[天文地球—海洋科学]