Chance of damage from an earthquake in 2017 based on the average of horizontal spectral response acceleration for 1.0-second period and peak ground acceleration

A one-year seismic hazard forecast for the Central and Eastern United States, based on induced and natural earthquakes, has been produced by the U.S. Geological Survey. The model assumes that earthquake rates calculated from several different time windows will remain relatively stationary and can be used to forecast earthquake hazard and damage intensity for the year 2017. This assessment is the first step in developing an operational earthquake forecast for the CEUS, and the analysis could be revised with updated seismicity and model parameters. Consensus input models consider alternative earthquake catalog durations, smoothing parameters, maximum magnitudes, and ground motion estimates, and represent uncertainties in earthquake occurrence and diversity of opinion in the science community. Near some areas of active induced earthquakes, hazard is higher than in the 2014 USGS National Seismic Hazard Model (NSHM) by more than a factor of 3; the 2014 NSHM did not consider induced earthquakes. In some areas, previously observed induced earthquakes have stopped, so the seismic hazard reverts back to the 2014 NSHM. This data set represents the results of calculations of hazard curves for a grid of points with a spacing of 0.05 degrees in latitude and longitude. It represents the chance of experiencing damaging earthquakes for fixed ground shaking levels that corresponds with MMI = VI. The values are obtained by averaging the probability of experiencing MMI = VI based on a peak ground acceleration value of 0.1155 g for site class D, and the probability of experiencing MMI = VI based on 1.0-second spectral acceleration value of 0.102 g for site class D. The data are for the Western United States and are based on the long-term 2014 National Seismic Hazard Model.

美国地质调查局（U.S. Geological Survey）基于人工诱发地震与天然地震，完成了美国中东部（Central and Eastern United States, CEUS）为期一年的地震危险性预测成果。该模型假设，通过多个不同时间窗计算得到的地震发生率将保持相对稳定，可用于2017年地震危险性与破坏烈度的预测。本次评估是构建CEUS业务化地震预测模型的第一步，后续可结合更新后的地震活动性数据与模型参数对分析结果进行修订。共识输入模型考量了地震目录时长、平滑参数、最大震级以及地面运动估算方案等多种备选方案，同时涵盖了地震发生的不确定性以及科学界的不同学术观点。在部分人工诱发地震活跃区域，本次预测的地震危险性较2014年美国地质调查局国家地震危险性模型（National Seismic Hazard Model, NSHM）高出3倍以上——2014年版NSHM未纳入人工诱发地震的影响。在部分区域，此前观测到的人工诱发地震已停止活动，因此地震危险性回归至2014年版NSHM的预测水平。本数据集包含了经纬度间隔0.05°的网格点的危险性曲线计算结果，代表了与修正麦加利烈度（MMI）VI级对应的固定地面震动水平下，遭遇破坏性地震的概率。该数值通过两种工况下的概率平均计算得到：一是基于场地类别D、峰值地面加速度0.1155g条件下遭遇MMI VI级地震的概率；二是基于场地类别D、1.0秒谱加速度0.102g条件下遭遇MMI VI级地震的概率。本数据集适用于美国西部地区，其构建基于2014年长期国家地震危险性模型。