摘要
2025年1月7日09时05分,西藏自治区日喀则市定日县(28.50°N,87.45°E)发生面波震级(Ms)6.8级地震。该地震事件及余震序列可能对冰川系统稳定性造成影响,诱发冰崩等次生灾害。为揭示震区冰川动态演变规律,本研究基于Landsat系列遥感影像与中国两期冰川编目数据,采用空间分析方法,系统分析了定日地震6度烈度区内冰川空间分布特征与动态变化。研究结果表明:(1)2023年,研究区有冰川659条,总面积达811.70 km^(2),冰储量为74.44 km^(3);(2)自1974年以来,研究区冰川总数减少307条(降幅31.78%),总面积缩减333.13 km^(2)(降幅29.10%),呈现显著退缩趋势,三个研究时期(1974年、2010年和2023年)的冰川退缩速率表现出“先快后缓”的阶段性特征;(3)气候变暖(1990—2024年气温上升2.7℃)是导致冰川退缩的主导因素,而冰湖扩张进一步加剧了冰川末端的消融过程。研究区典型冰川的厚度与表面流速均发生显著变化,冰川预估模型预测该区域冰川未来仍将持续消融。建议重点关注地震对冰川内部结构的潜在影响,加强地震灾害对冰川动力过程影响的定量评估,同时应加强对大型冰川及重点冰湖的动态演化监测,以有效防范可能由地震触发的灾害链效应。
On 7 January 2025 at 09:05(UTC+8),an earthquake with a surface-wave magnitude(M_(s))of 6.8 struck Tingri County(28.50°N,87.45°E),Shigatse City,Xizang Autonomous Region.This earthquake and its aftershock sequence may have affected glacier system stability,potentially triggering secondary hazards such as ice avalanches.To investigate the dynamic evolution patterns of glaciers in the affected region,this study sys⁃tematically analyzed the spatial distribution characteristics and dynamic changes of glaciers within the seismic in⁃tensity VI zone of the Tingri earthquake using Landsat series remote sensing images and two phases of China’s glacier inventory data,combined with spatial analysis methods.The results showed that:(1)as of 2023,the study area contained 659 glaciers with a total area of 811.70 km^(2)and an ice volume of 74.44 km^(3).(2)Since 1974,the number of glaciers in the study area decreased by 307(a reduction of 31.78%),while the total glacier area diminished by 333.13 km^(2)(a decline of 29.10%),demonstrating a significant retreat trend.The retreat rates of glaciers across the three study periods(1974,2010,and 2023)exhibited a phased characteristic of“rapid initial decline followed by gradual deceleration”.(3)Climate warming(with a temperature increase of 2.7°C from 1990 to 2024)was identified as the primary driver of glacier retreat,while glacial lake expansion further ac⁃celerated melting at the glacier terminus.The thickness and surface flow velocity of typical glaciers in the study area have undergone substantial changes.Glacier projection models predicted that glaciers in this region would continue to melt in the future.It is recommended to focus on the potential impact of earthquakes on the internal structures of glaciers and strengthen the quantitative assessment of the impact of earthquakes on glacial dynam⁃ics.Additionally,dynamic evolution monitoring of large glaciers and critical glacial lakes should be enhanced to effectively mitigate potential disaster chain effects triggered by earthquakes.
作者
王文
聂勇
吴宇宏
谷昌军
吕其元
WANG Wen;NIE Yong;WU Yuhong;GU Changjun;LÜQiyuan(Key Laboratory of Mountain Hazards and Engineering Resilience,Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610213,China;National Disaster Reduction Center of China,Ministry of Emergency Management,Beijing 100124,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《冰川冻土》
2025年第4期914-926,共13页
Journal of Glaciology and Geocryology
基金
中国电建集团西北勘测设计研究院有限公司重大科技项目(XBY-ZDKJ-2023-9)
西藏自治区科技计划项目重点研发计划(XZ202301ZY0016G)
国家自然科学基金项目(42171086)资助。
关键词
定日地震
冰川
气候变化
喜马拉雅
遥感监测
Tingri earthquake
glacier
climate change
Himalayas
remote sensing monitoring
