Chance of damage from an earthquake in 2016 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 2016. 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 (NHSM) by more than a factor of 3; the 2014 NHSM 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 Central and Eastern United States and are based on the one-year model described above.美国地质调查局（U.S. Geological Survey）针对美国中部及东部地区（Central and Eastern United States, 简称CEUS），基于诱发地震与天然地震，完成了一份为期一年的地震危险性预测成果。 该模型假定，通过多组不同时间窗计算得到的地震发生率将维持相对稳定，可用于推演2016年的地震危险性与破坏烈度。 本次评估是构建CEUS业务化地震预测体系的第一步，后续可通过更新地震活动性数据与模型参数对本次分析结果进行修订。 共识输入模型综合考量了多种备选方案，包括不同的地震目录时长、平滑参数、最大震级以及地面运动估计模型，同时覆盖了地震发生过程的不确定性以及科学界的学术观点分歧。 在部分诱发地震活跃区域，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, 简称NHSM）高出3倍以上——2014年版NHSM未纳入诱发地震因素。而在部分区域，此前观测到的诱发地震已停止活动，因此当地地震危险性回归至2014年版NHSM的预测结果。 本数据集包含了经纬度间隔为0.05度的网格点的危险性曲线计算结果，其表征了对应于麦加利地震烈度（Modified Mercalli Intensity, 简称MMI）VI级的固定地面震动水平下，遭遇破坏性地震的概率。 该数值通过两种场景下的概率取平均得到：一是基于场地类别D，峰值地面加速度为0.1155g时对应MMI VI级的概率；二是基于场地类别D，1.0秒谱加速度为0.102g时对应MMI VI级的概率。 本数据集适用于美国中部及东部地区，所有结果均基于前文所述的一年期预测模型生成。