A Method for Producing Digital Probabilistic Seismic Landslide Hazard Maps: An Example from the Los Angeles, California, Area
A Method for Producing Digital Probabilistic Seismic Landslide Hazard Maps: An Example from the Los Angeles, California, Area
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DOI：
10.3133/ofr98113
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
R. Jibson;E. Harp;John A. Michael
中科院分区：
文献类型：
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作者：
R. Jibson;E. Harp;John A. Michael
1994年加州北岭地震是我们拥有对地震边坡不稳定性进行严格区域分析所需的所有数据集的第一次地震。这些数据集包括（1）触发滑坡的全面清单，（2）主震的大约200个强震记录，（3）该地区1：24，000比例尺的地质测绘，（4）地质单元工程特性的广泛数据，以及（5）地形的高分辨率数字高程模型。所有这些数据集都已在ARC/INFO地理信息系统平台上以10米网格间距数字化和光栅化。结合这些数据集在一个动态模型的基础上纽马克的永久变形（滑块）分析产生估计同震滑坡位移在每个网格单元从北岭地震。然后将模拟的位移与北岭地震引发的滑坡的数字库存进行比较，以构建预测位移与失效概率之间的概率曲线。该概率函数可用于预测和绘制任何感兴趣的地面震动条件下失效概率的空间变异性。我们预计，这一映射过程将被用来构建地震滑坡灾害地图，这将有助于应急准备规划，并在合理的决策，对发展和建设的地区容易发生地震边坡失稳。
The 1994 Northridge, California, earthquake is the first earthquake for which we have all of the data sets needed to conduct a rigorous regional analysis of seismic slope instability. These data sets include (1) a comprehensive inventory of triggered landslides, (2) about 200 strong-motion records of the mainshock, (3) 1:24,000-scale geologic mapping of the region, (4) extensive data on engineering properties of geologic units, and (5) high-resolution digital elevation models of the topography. All of these data sets have been digitized and rasterized at 10-m grid spacing in the ARC/INFO GIS platform. Combining these data sets in a dynamic model based on Newmark’s permanent-deforma tion (sliding-block) analysis yields estimates of coseismic landslide displacement in each grid cell from the Northridge earthquake. The modeled displacements are then compared with the digital inventory of landslides triggered by the Northridge earthquake to con struct a probability curve relating predicted displacement to probability of failure. This probability function can be applied to predict and map the spatial variability in failure probability in any ground-shaking conditions of interest. We anticipate that this mapping procedure will be used to construct seismic landslide hazard maps that will assist in emer gency preparedness planning and in making rational decisions regarding development and construction in areas susceptible to seismic slope failure.