【摘要】 2024年1月23日新疆乌什发生M_S7.1地震，震中位于西南天山乌什凹陷，极震区烈度为Ⅸ度。此次地震是新疆地区近十年以来最大的地震，也是自1992年吉尔吉斯斯坦Suusamyr M_S7.3地震以来天山地震带内最大的地震。地震造成的人员伤亡、房屋破坏相对较轻，但次生地质灾害较为严重。文中通过震后第一时间野外科学考察、大比例尺卫星影像解译及无人机航拍，对宏观震中及震区地质灾害的空间位置、基本类型和发育特征等进行了调查。结果表明，乌什地震宏观震中主要位于微观震中以南约8km的别迭里河—恰勒玛提河之间，地质灾害主要沿构造走向集中分布在微观震中东、西两侧30km范围内的山区，灾害类型多以岩崩、滑坡、滚石、边坡失稳和地裂缝为主，尤其以地震崩塌和地裂缝最为突出，偶有沿地裂缝的喷砂冒水现象，地震崩塌主要集中在玉山古溪河—科克留木苏河之间，震中所在的别迭里河表现最为明显，地裂缝主要集中在由新近系地层组成的别迭里背斜核部，以张裂缝和张剪裂缝为主，覆盖范围南北长2.53km,东西宽0.2～1.2km,面积约为2.2km~2。本次调查的次生地质灾害的分布区与InSAR同震形变场给出的最大形变区在空间上具有较好的一致性，表明构造变形对地质灾害形成具有显著的控制作用。更多还原

【Abstract】 The Wushi M_S 7. 1 earthquake is the largest seismic event in Xinjiang in the past decade and the most significant earthquake in the Tianshan seismic belt since the Suusamyr M_S 7. 3 earthquake in Kyrgyzstan in 1992. The microseismic epicenter is located at the transition between the Keping nappe structure belt and the Kuqa nappe belt in the southwestern Tianshan Mountains, near the intersection of the southern Tianshan Mountains and the Wushi Depression. This region is a compressional fault depression valley formed in the context of Tianshan orogeny. The northern boundary of the valley is controlled by the Maidan reverse fault zone, while multiple rows of newly developed linear uplifts and piedmont fault scarps in the northern depression are governed by low-angle overthrust and recoil faults.Focal mechanism analysis indicates that both the main shock and aftershocks exhibit a compressional thrust-type mechanism, consistent with the structural characteristics of the Wushishan front depression. Post-earthquake investigations revealed relatively minor casualties and structural damage,but secondary geological disasters were severe. Using field surveys, large-scale satellite image analysis, and drone aerial photography conducted immediately after the earthquake, this study investigates the spatial distribution, types, and development characteristics of seismic-induced geological hazards in various gullies within the affected region. Although no large-scale surface ruptures were observed at or near the epicenter, extensive seismic geological hazards were identified,providing crucial insights for determining the macroseismic epicenter and assessing the post-disaster intensity and loss in the earthquake area.Geological hazards induced by the Wushi earthquake were primarily concentrated in Biediligou,Qialematigou, Cocriu Musugou, and adjacent mountainous areas within the VII-degree seismic intensity zone. The most severe damage occurred in the Biediligou-Qialematigou region, where the macroseismic epicenter was located, with diverse types of secondary disasters, including rockfalls, landslides, rolling stones, bank slope collapses, subgrade settlement cracks, and ground fissures. Some ground fissures were accompanied by displacement. Seismic geological hazards were predominantly observed near the microseismic epicenter and within 10km of the north and south sides of the fault zone, with collapses being the most prominent, followed by pavement cracking and riverbank slope failures caused by ground fissures and uneven subgrade settlement. Post-earthquake investigations also identified numerous concentrated surface tension and shear cracks in the macroseismic epicenter,alongside earthquake-induced collapses, landslides, slope instabilities, subgrade settlements, and structural failures. Coseismic InSAR deformation field and image offset analysis revealed a maximum line-of-sight displacement of approximately 40cm and a minimum displacement of -16cm. The long axis of the deformation zone trends NE, with its strongest deformation occurring between Biediligou and Qialamatigou. This spatial distribution aligns well with the observed ground fissures and seismic deformation zones near the macroseismic epicenter, indicating that structural deformation plays a critical role in controlling the formation of earthquake-induced geological hazards.更多还原