基于GIS的西藏地区活动构造分布特征及地震灾害危险性分析

西藏地区是中国地震灾害发生频率最高的地区。近年来,随着全球气候变化和地壳运动加快导致的地质灾害也日趋频繁和严重。同时,频繁的地震灾害所引发的崩塌、滑坡等地质灾害也是制约西藏地区农牧业发展和经济持续增长的重要因素之一。农牧业作为西藏的重要产业,对于提高西藏农牧业防灾减灾水平、避免人员与经济遭受重大损失具有重大的现实意义。通过地理信息系统(geographic information system, GIS)技术对西藏地区活动构造特征进行可视化显示,并对西藏地区2007—2018年发生的地震分布与活动构造带进行叠加分析;在查阅相关文献和地区史料数据的基础上,分析西藏地区的地震易发性与危险性,并作图显示。结果表明:西藏地区地震频率高发生区域占比26.48%,较高发生区域占比17.04%,中发生区域占比34.44%,较低发生区域占比18.89%,低发生区域占比3.15%。

Distribution of active structure and seismic hazard in Tibet based on GIS

Tibet is the region with the highest frequency of earthquake disasters in China. Especially in recent years, geological disasters caused by global climate change and the acceleration of crustal movement have become increasingly frequent and serious. At the same time, geological disasters such as collapse and landslide caused by frequent earthquake disasters are also one of the important factors that restrict the development of agriculture and animal husbandry in Tibet and the sustained economic growth. As an important industry in Tibet, agriculture and animal husbandry has great practical significance for improving the level of disaster prevention and mitigation in Tibet''s agriculture and animal husbandry and avoiding major losses to personnel and the economy. In this paper, the GIS technology is used to visualize the characteristics of the active structures in Tibet, and the seismic distribution and active tectonic belts in Tibet from 2007 to 2018 are superimposed. Based on the review of relevant literature and regional historical data, the earthquake vulnerability and risk in Tibet were analyzed and plotted. The results showed that the high occurrence area accounted for 26.48%, the higher occurrence area accounted for 17.04%, the middle occurrence area accounted for 34.44%, the lower occurrence area accounted for 18.89%, and the low occurrence area accounted for 3.15%.