渤海某区块浅层气对工程影响的评估  

Assessment of Impact of Shallow Gas on Engineering in a Block in Bohai Sea

作　　者：刘双双[1] 沈志明[1] 刘政发 刘剑涛[1] 冯湘子[1] 朱友生 LIU Shuangshuang;SHEN Zhiming;LIU Zhengfa;LIU Jiantao;FENG Xiangzi;ZHU Yousheng(China Oilfield Services Limited,Tianjin 300459,China)

机构地区：[1]中海油田服务股份有限公司,天津300459

出　　处：《中国海洋平台》2024年第3期80-87,97,共9页China offshore Platform

摘　　要：以渤海某区块项目为例,采用保压取样方法获取待评估区域海底土层样品并对所含气体开展组分测定,定性判断浅层气成因。采用静力触探孔压消散试验方法获取地层中超孔隙水压力,定量评估对含浅层气地层承载力的折减效应。结果表明,内浅层气主要组分为甲烷和二氧化碳,气体含量较低。内地层中的浅层气可能属于生物成因气。含浅层气地层的超孔隙水压力相对上覆有效压力比值约3%,承载力折减因数为1.0%~1.1%。所采取的方法能够有效评估浅层气对海上基础设施和生产安全的影响程度,具有推广价值。Taken a project in a block in Bohai Sea as an example,the pressure-holding sampling method is used to obtain the seabed soil samples to be assessed,and the gas components are determined to qualitatively determine the origin of the shallow gas.The excess pore water pressure in the formation is obtained by dissipation of pore pressure test based on cone penetration test to quantitatively evaluate the reduction effect on the bearing capacity of the formation with shallow gas.The results show that the main components of the shallow gas in the study area are methane and carbon dioxide,and the shallow gas content is relatively low.The shallow gas in the inland layer is possibly biogenic gas.The ratio of the excess pore water pressure to the overlying effective stress in the formation with shallow gas is about 3%,and the bearing capacity reduction factor in the formation with shallow gas is from 1.0%to 1.1%.The method adopted can effectively evaluate the impact of the shallow gas on offshore infrastructure and production safety,and is of promotion value.

关 键 词：浅层气 气体组分 孔压消散 地层承载力折减因数 

分 类 号：P752[天文地球—海洋科学] P736[石油与天然气工程—油气田开发工程] TE42