2022年6月阿富汗帕克提卡M6.0级地震前微波亮温异常的多态性及其归因辨析  

Discriminating the polymorphism and attribution of microwave radiation anomalies related to the June 2022 Mw 6.0 Paktita earthquake in Afghanistan

作　　者：丁逸凡 吴立新[1,2] 齐源 毛文飞 DING Yifan;WU Lixin;QI Yuan;MAO Wenfei(School of Geoscience and Info-Physics,Central South University,Changsha 410083,China;Laboratory of Geo-Hazards Perception,Cognition and Predication,Central South University,Changsha 410083,China)

机构地区：[1]中南大学地球科学与信息物理学院,长沙410083 [2]中南大学地灾感知认知预知研究室,长沙410083

出　　处：《遥感学报》2024年第10期2621-2631,共11页NATIONAL REMOTE SENSING BULLETIN

基　　金：国家自然科学基金重点项目(编号:41930108);国家重点研发计划(编号:2018YFC15035);战略性科技创新合作重点专项(编号:2023YFE020800);中南大学研究生自主探索创新项目(编号:2023ZZTS0703)。

摘　　要：阿拉伯板块持续向北挤压欧亚板块,促使阿富汗—巴基斯坦边境应力场变化、局部闭锁和破裂失稳,导致2022年6月21日发生了6.0级帕克提卡浅源地震,这是该地区近10年发生的最大地震。本文利用GCOM-W1卫星AMSR-2微波辐射计观测的微波亮温(MBT)数据,运用时空加权两步法提取了地震前后、震中周边超百万km^(2)范围内的MBT残差,揭示了MBT时空演变特征与正异常现象的多态性。联合降雨、土壤湿度及CH4、CO温室气体卫星观测数据,结合区域地质条件和地表覆盖类型,逐一进行了多态MBT正异常的归因辨析。研究表明:(1)震中东南部印度河平原和西北部卡拉库姆沙漠显现MBT正异常,可归因于孕震应力激活的岩石空穴粒子(P-hole)从孕震区向上传递到第四系盖层,导致地表浅层介电常数降低;(2)临震期高山地区显现MBT正异常,可归因于应力激活的P-hole向高山低温区传递,并聚集在砂性沉积岩盖层,致使砂性盖层微波介电常数降低;(3)震中西北部沿赫拉特断裂带显现MBT正异常,与临震期断层拉张有关,可能受到煤系CH4、CO沿断层与矿井逸出产生的温室效应影响。本研究对于西亚地区地震微波遥感观测及地震异常识别有重要意义,对全球其他地区的地震遥感监测及异常认知也有参考价值。The Arabian plate continues to squeeze the Eurasian plate northward,which promotes stress field changes,local stress locking,and rupture instability.This phenomenon resulted in the magnitude 6.0 shallow earthquake on June 21,2022 in Paktita province on the Afghanistan-Pakistan border,which is the largest earthquake in the region in the past 10 years.Studying the phenomenon and mechanism of earthquakes is crucial.By analyzing an earthquake case with multisource data,the eternal earth science topic of earthquake perception and cognition is studied deeply.In this study,the Microwave Brightness Temperature(MBT)data collected by the AMSR-2 radiometer of the Aqua satellite was used to extract pre-earthquake and postearthquake MBT residuals within more than a million square kilometers around the epicenter by using a spatiotemporally weighted two-step method,revealing the spatiotemporal evolution characteristics of MBT and the polymorphism of positive MBT anomalies.On the basis of the data of precipitation,soil moisture,regional geological map,land cover,and greenhouse gases,such as CH4 and CO,the attribution analysis of positive polymorphic MBT anomalies was discriminated one by one.We found that(1)the positive MBT anomaly in the Indus Plain,southeast of the epicenter,and the positive MBT anomaly in the Karakum desert,northwest of the epicenter,could be attributed to the cavity particles(P-hole)activated by the seismogenic stress,transferring from the seismogenic area to the Quaternary overburden along the stress gradient,which reduces the dielectric constant of the dielectric constant in shallow surface layer;(2)the positive MBT anomaly in the alpine area during the earthquake period could be attributed to the transfer and accumulation of stress-activated P-hole to the alpine low-temperature area,which resulted in the decrease in the microwave dielectric constant of the sandy layer;(3)the positive MBT anomaly along the Herat Fault,northwest of the epicenter,was related to the fault stretching during the imminent earthq

关 键 词：遥感 微波亮温 地震异常 P-hole 微波介电 温室效应 地应力场变化 

分 类 号：P237[天文地球—摄影测量与遥感] P2[天文地球—测绘科学与技术]