基于时序InSAR技术的辽河三角洲油田地面沉降监测与建模

Monitoring and Modeling of Land Subsidence in Liaohe Delta Oilfield Based on Time Series InSAR Technology

辽河三角洲油田的持续性开采导致严重地表沉降,影响石油采收率和油田生产作业,对地表基础设施乃至生态环境也构成威胁。为保证该区域石油等地下流体资源的安全开采和区域生态环境保护,通过将相干性信息作为权重融入小基线集合成孔径雷达干涉测量(interferometric synthetic aperture radar,InSAR)技术中,获取辽河三角洲地区2017-2020年地表形变信息。采用升降轨数据融合分解方法,提取曙光油田区域的垂直及水平东西向形变,并对曙光采油厂储层压实引起的地面沉降进行储层压实与沉降模型反演。结果显示:(1)辽河三角洲区域内存在多处地面沉降,曙光采油厂和欢喜岭采油厂沉降最为明显,视线向平均沉降速率分别达到158 mm/a和73 mm/a;(2)曙光油田呈现出向油田沉降漏斗中心水平移动的规律,且东西两侧移动速率量级基本一致,最大水平移动速率达到-62 mm/a(朝西运动);(3)基于曙光油田储层参数构建的储层压实与沉降模型能较好地对油田沉降中心最大沉降量位置进行反演,且沉降范围和量级与InSAR观测结果较为一致。

Objectives:The continuous exploitation of the Liaohe Delta oilfield has resulted in severe surface subsidence,impacting oil recovery rates,production operations,and posing threats to surface infrastructure and ecological environments.To ensure the safe exploitation of underground fluid resources and protect the regional environment,monitoring implementation is needed for this region.Methods:The method of small baseline subset interferometric synthetic aperture radar(SBAS-InSAR)technology with coherence information as weights was used to analyze the surface deformation.Using the fusion decomposition of synthetic aperture radar descending and ascending orbit results to extract both vertical and horizontal east-west deformation within the Shuguang oilfield area.Subsequently,a reservoir compaction-induced subsidence inversion model is applied to the Shuguang oilfield to simulate and interpret the observed subsidence phenomena, linking them to theunderground fluid resource exploitation activities.Results: The results reveal significant ground subsidencethroughout the Liaohe Delta region, particularly in the Shuguang oilfield and Huanxiling oilfield. The averageline of sight subsidence rates reaching 158 mm/a and 73 mm/a, respectively. In the Shuguang oilfield, thereis horizontal movement towards the subsidence center, with approximately equal magnitudes of movement onthe east and west sides. The maximum horizontal movement rate is observed to be − 62 mm/a (westwardmotion). Furthermore, the reservoir compaction and subsidence model based on Shuguang oilfield reservoirparameters effectively invert the maximum subsidence position at the center of the oilfield, with subsidence rangeand magnitude consistent with the InSAR observation results. Conclusions: The study concludes that continuousexploitation of oil has led to significant ground subsidence in the Liaohe Delta region, especially in Shuguangoilfield and Huanxiling oilfield, with clear patterns of subsidence and horizontal movement detected using SBASInSARtechnology. The developed reservoir compaction-induced subsidence inversion model proves effectivein simulating subsidence phenomena associated with oilfield operations. These findings underscore the importanceof monitoring and managing subsidence risks to ensure the safe exploitation of underground resources and toprotect regional ecological environments in the Liaohe Delta region.