基于动态更新地震动参数的地震滑坡灾情快速评估模型研究

A spatial database including seismic landslide inventory, earthquake data，related geological environmental conditions and element at risk will be constructed in Guanzhong-Tianshui region as case study area. With the help of geostatistic analysis, which geological environmental conditions and their combination prone to failure in specific types and magnitude landslide during specific magnitude earthquake and to what degree different types of element at risk affected will be preliminary revealed. The feature of dynamic updated ground motion parameters generated by different methods which based on different earthquake source rupture process，seismicwave propagation，and site response models will be comprehensive analyzed. According to the ground motion parameter types, accuracy and timeliness, empirical models, statistical models and physical mechanics models will be integrated for dynamic rapid seismic landslide hazard mapping constrained by accuracy and timeliness. To what degree different types of element at risk affected by specific types and magnitude seismic landslide，such as degree of towns buried, traffic and river blocked, etc, will be analyzed and models will be presented. Combined with the spatial data availability, accuracy and post earthquake emergency rescue requirement, rapid dynamic regional seismic landslide loess assessment methodology and indicators will put forward based on GIS, which can provide rapid seismic landslide loess information in 1 hour, 4 hours and 6 hours post earthquake in different accuracy with evolving quality, especially on critical information for emergency rescue force deployment in damaging earthquake response in mountainous, such as landslide potential buried town, blocked traffic or river, and so on.

建立以关中天水地区为研究区的地震滑坡编录、地震数据、基础地质环境条件及承灾体空间数据库，利用统计分析方法揭示什么地质环境条件及其组合易在地震时形成特定类型与规模的地震滑坡，特定类型与规模的地震滑坡对不同类型承灾体的损伤程度。综合分析基于不同震源、波传播和场地反应模型的方法获取的动态更新的地震动参数的特征。根据地震动参数的类型、精度及时效性，研究集成满足时效性和精度需求的区域地震滑坡危险性评估的经验模型、统计模型和物理力学方法，提出城镇人口埋压、交通阻断、河流堰塞等地震滑坡灾情预测评估的模型。结合空间数据的可获取性、精度和震后应急救援需求，提出区域地震滑坡灾情快速预测评估的技术流程及指标体系、研发基于GIS的动态地震滑坡快速灾情评估的关键技术，实现山区强震后1小时、4小时、6小时不同精度的城镇埋压、交通阻断、河流堰塞等关键地震滑坡灾情信息的动态更新。

我国是世界上地震滑坡最为发育和损失最为惨重的国家之一，地震滑坡灾情信息是山区强震应急救援和防范震后地质灾害的关键信息，其获取的小时级时效性要求，常规手段难以满足，亟需研发地震滑坡灾情快速评估技术方法，满足山区强震应急救援需求。本项研究将小时级动态更新的地震动参数与地震滑坡危险性评估技术整合，重点研究快速灾情评估模型、技术流程，并研发基于ARCGIS软件模块，实现了地震滑坡灾情快速评估与多地震情景滑坡灾害危险性评估。结合地质调查项目，初步建立了关中天水地区的地震滑坡编录、历史地震数据、活动断层和潜在震源区划等基础地质环境条件空间数据库。初步查明了关中盆地正断层系诱发地质灾害的分布特征与历史地震滑坡的强度衰减特征，揭示了天水地区走滑断层系触发灾害的分布特征与控制因素，分析了断层带滑坡、低角度滑动型滑坡、旋转型滑坡、崩滑型滑坡、高位剪出型滑坡等5种滑坡的成因机制和空间分布规律。利用大量强震数据，对现有阿里亚斯烈度（Arias Intensity）衰减关系的适用性进行了系统深入的讨论，初步建立了我国的阿里亚斯烈度衰减关系。研究提出了不同尺度地震滑坡危险性评估技术流程和软件方法，重点融合概率地震危险性和滑坡危险性评估技术，完善了概率地震滑坡危险性评估技术流程，可计算获得潜在地震滑坡的空间分布概率和利用动态更新的地震动参数快速评估地震滑坡灾情。初步完成南北活动构造带、天水地区不同尺度地震滑坡危险性和风险评估，为潜在强震山区灾情快速评估奠定了基础。项目实施期间，累计发表核心期刊论文12篇，其中国际SCI论文7篇，取得2项软件著作权，培养博士研究生2名，先后开展了鲁甸地震、九寨沟地震灾区的地震滑坡灾情快速评估，为震后地质灾害应急提供了技术支撑。