包雨鑫,孙建宝,李涛,梁存任,詹艳,韩静,李永生,张景发. 2022. 基于InSAR数据分析四川盆地南部长宁页岩气区块地表形变场基本特征. 地震学报,44(3):427−451. doi: 10.11939/jass.20210064
引用本文: 包雨鑫,孙建宝,李涛,梁存任,詹艳,韩静,李永生,张景发. 2022. 基于InSAR数据分析四川盆地南部长宁页岩气区块地表形变场基本特征. 地震学报,44(3):427−451. doi: 10.11939/jass.20210064
Bao Y X,Sun J B,Li T,Liang C R,Zhan Y,Han J,Li Y S,Zhang J F. 2022. Characteristics of surface deformation field of Changning shale gas block in southern Sichuan basin with InSAR data. Acta Seismologica Sinica44(3):427−451. doi: 10.11939/jass.20210064
Citation: Bao Y X,Sun J B,Li T,Liang C R,Zhan Y,Han J,Li Y S,Zhang J F. 2022. Characteristics of surface deformation field of Changning shale gas block in southern Sichuan basin with InSAR data. Acta Seismologica Sinica44(3):427−451. doi: 10.11939/jass.20210064

基于InSAR数据分析四川盆地南部长宁页岩气区块地表形变场基本特征

Characteristics of surface deformation field of Changning shale gas block in southern Sichuan basin with InSAR data

  • 摘要: 近年来随着我国页岩气大规模开采,四川盆地南部活动构造相对稳定的地区出现了一系列微震和有感地震,甚至是破坏性地震。这些地震是否为工业开采所诱发,目前已有研究从时空相关性给出了一些统计推断,本文则从形变观测角度分析页岩气开采能否产生可以检测到的地面形变,以揭示形变信息与页岩气开采的关系,尝试为页岩气开采提供有效的监测手段。基于长波ALOS-2卫星雷达数据对长宁页岩气区块近两三年内的InSAR地表形变展开探测,检测页岩气大规模生产可能造成的地面形变及其基本特征,同时使用Sentinel-1卫星雷达数据分析页岩气开发活跃时段内的形变时间序列信息。结果显示:考虑到不同观测技术的误差水平和观测角度差异,两种卫星数据均反映了一致的地表形变分布,且形变场与页岩气开采井的空间分布有很好的对应关系;压裂注液过程会造成地表快速隆升,生产过程中随着流体扩散地表会出现沉降和水平运动,初步揭示出页岩气生产过程中地面形变的非稳态变形特征。这表明在四川盆地南部复杂的形变观测条件下,InSAR技术是页岩气开采有效的监测手段,能够弥补地震学观测的不足。

     

    Abstract: In recent years, along with large-scale development of shale gas, the seismicity rate has increased dramatically, a series of microseismicity, felt earthquakes and even destructive earthquakes occurred in southern Sichuan basin, a relatively tectonic stable area. Some studies statistically infer whether these earthquakes were induced by industrial activities by using spatio-temporal correlations. This study, on the other hand, uses deformation measurements to analyze whether shale gas exploitation can produce detectable surface deformation, so as to analyze the relationship between deformation and shale gas exploitation, in an attempt to find an effective approach for shale gas exploitation monitoring. Long wavelength ALOS-2 satellite radar data has the potential for minimizing decorrelation effects of radar signals caused by vegetation, heavy water vapor and topographic relief in Sichuan basin. We used ALOS-2 InSAR data to measure surface deformation in Changning shale gas block in the past two or three years, found possible ground deformation caused by massive shale gas production and analyzed its basic characteristics. Meanwhile we also processed time-series of Sentinel-1 satellite radar data to measure the surface deformation during active periods of shale gas exploitation. Considering the errors and different observation geometries of the two datasets, the results from two databases are consistent in revealing the surface deformation. Furthermore, the meaured deformation field is in agreement with the spatial distribution of shale gas wells. Our observations show fast surface uplift during hydrofracture injection, also ground subsidence and horizontal motion in production period with fliud diffusion. We preliminarily reveal the non-steady deformation characteristics during shale gas production. Our study suggests that InSAR is an effective technique for shale gas production monitoring even in southern Sichuan basin where complex deformation occurs, and can provide insights supplementary for seismological observations.

     

/

返回文章
返回