基于高精度时变微重力方法研究呼图壁储气库地下介质密度变化特征  

STUDY ON THE DENSITY VARIATION CHARACTERISTICS OF UNDERGROUND MEDIUM IN HUTUBI GAS STORAGE BASED ON HIGH-PRECISION TIME-VARYING MICROGRAVITY METHOD

作　　者：刘代芹 玄松柏[5] 陈石 艾力夏提·玉山[2,3] 李杰 王晓强 李瑞[2,3] LIU Dai-qin;XUAN Song-bai;CHEN Shi;AILIXIATI·Yushan;LI Jie;WANG Xiao-qiang;LI Rui(School of Earth and Space Sciences,University of Science and Technology of China,Hefei 230026,China;Xinjiang Pamir Intracontinental Subduction National Field Observation and Research Station,Urumqi 830011,China;Urumqi Institute of Central Asia Earthquake,China Earthquake Administration,Urumqi 830011,China;Earthquake Agency of Xinjiang Uygur Autonomous Region,Urumqi 830011,China;Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China;Institute of Geophysics,China Earthquake Administration,Beijing 100081,China)

机构地区：[1]中国科学技术大学地球和空间科学学院,合肥230026 [2]新疆帕米尔陆内俯冲国家野外科学观测研究站,乌鲁木齐830011 [3]中国地震局乌鲁木齐中亚地震研究所,乌鲁木齐830011 [4]新疆维吾尔自治区地震局,乌鲁木齐830011 [5]中国科学院上海天文台,上海200030 [6]中国地震局地球物理研究所,北京100081

出　　处：《地震地质》2022年第2期414-427,共14页Seismology and Geology

基　　金：新疆天山青年计划(杰出青年)基金(2017Q010);新疆维吾尔自治区重点研发专项(2020B03006-2);新疆维吾尔自治区自然科学基金(2016D01A062、2020D01A84、2020D01A85、2022D01A106);国家自然科学基金(41874015);地震科技星火计划项目(XH22007YA);新疆地震局科技创新团队计划(XJDZCXTD2020-1)共同资助。

摘　　要：文中利用呼图壁地下储气库7期流动重力资料,采用经典平差整体计算,得到研究区域内各监测点的相对重力变化量,结合储气库注采压力的相关数据,获取该区域重力场时空变化特征与注采压力之间的响应关系图像,最后以呼图壁地下储气库地表观测的重力场动态变化数据为基础,采用地下密度变化异常体空间分布的紧凑重力反演算法模拟计算呼图壁储气库地下物质的密度时序变化及库体的形态构造的分布特征。研究表明,根据不同时期地下储气库注采变化量的差异,模拟计算得到呼图壁储气库地下密度变化的最佳深度约为3500m,其地下物质介质密度变化的最大值约为±0.7kg/m^(3)。不同时期的密度变化图像也可清晰地反映出该储气库内部的构造结构呈NW-SE走向,且库体内构造形态结构分布与呼图壁储气库地质构造的分布特征基本吻合。In this paper,based on microgravity time-varying signals,the gravity field and underground medium density change of Hutubi gas storage were simulated and calculated,and the response relationship between gravity change and injection-production pressure was analyzed.By using the 7 phases of mobile gravity data of Hutubi underground gas storage,adopting the classical adjustment method and selecting the absolute gravity points of HKPN,HKPS and Urumqi(BJ00)and Shihezi gravity point(BJ06)of CMONOC around the gas storage area as the calculation basis,the relative gravity variation of each monitoring point in the study area was obtained with the precision ranging(3~5)×10-8m/s~2 for each point in each phase.Combined with the relevant data of gas storage injection-production pressure,the response relationship image between the spatial-temporal variation characteristics of gravity field and injection-production pressure in this area was acquired.The research shows that the gravity change in the entire survey area exhibits zoning characteristics.The gravity change in the outer area of the gas storage south of Hutubi Fault is relatively small,and the gravity change in the gas storage area increases and decreases alternately.Especially in the east side of the reservoir area,the gravity change shows obvious characteristics of decreasing in spring and increasing in autumn,which causes the natural gas in the gas storage to basically drop to the lowest in March,thus resulting in the minimum internal stress in the gas storage.According to the theory of crustal stress equilibrium,when the pressure inside the gas storage tends to increase or decrease,the stress outside the gas storage will be adjusted correspondingly.When the gas injected into the gas storage spreads between the rocks and their gaps in the gas storage,it will exert a certain pressure on the rocks,causing the medium density in the underground gas storage cavity to vary in different degrees,thus resulting in the changes in the gravity values of the surface measuring p

关 键 词：呼图壁储气库 时变微重力 介质密度 注采压力 

分 类 号：P315.726[天文地球—地震学]