Third Uniform California Earthquake Rupture Forecast (UCERF3) Fault System Solutions

Data files for the Third Uniform California Earthquake Rupture Forecast (UCERF3), as described in https://doi.org/10.1785/0120130164. These data are stored in the original UCERF3 Fault System Solution file format, which uses binary files within zip containers. This format is being revised, and updates to this dataset will be published when the new and more user friendly format is finalized. See https://opensha.org/File-Formats for more information. File descriptions: Branch Averaged Files These files contain branch-averaged fault system solutions, where rupture properties (magnitude, rake, rate of occurrence, etc) are averaged across all UCERF3 logic tree branches, according to each branch's weighting in the final model. This is the simplest version of the model, and can be used as a quick approximation to mean hazard. One file exists for each fault model, and these files are compatible with the time-dependent version of UCERF3. branch_averaged_ucerf3_sol_FM3_1.zip - fault model 3.1 branch averaged fault system solution branch_averaged_ucerf3_sol_FM3_2.zip - fault model 3.2 branch averaged fault system solution Full Model (Compound Solutions) These files contain the full UCERF3 logic tree, and can be used to extract data for individual logic tree branches (e.g., for use in hazard calculations that consider all epistemic uncertainties). full_ucerf3_compound_sol.zip - full compound solution file with information on all 1,440 time-independent logic tree branches full_ucerf3_compound_sol_with_individual_runs.zip - same as above, but also containing rates for each of 10 simulated annealing inversion runs for each logic tree branch (total of 14,400 inversions) True Mean Solutions A different type of branch averaged solution, the “true mean” solution, is also available. They are similar to the branch averaged fault system solution described above, but instead use duplicate versions of each rupture whenever a key property (rake, magnitude, area) changes. This retains all variability allowing for quick reproduction of mean UCERF3 results with a minimum set of ruptures. The MeanUCERF3 ERF implemented in OpenSHA uses these files and also allows the user to apply various approximations to further reduce the rupture count. Note: These solutions are not compatible with time dependent UCERF3 calculations as multiple instances of each subsection may exist, resulting in rate partitioning between instances and incorrect recurrence intervals for renewal model calculations. true_mean_ucerf3_sol.zip - true mean fault system solution, across both fault models true_mean_ucerf3_sol_FM3_1.zip - true mean fault system solution, only for fault model 3.1 true_mean_ucerf3_sol_FM3_2.zip - true mean fault system solution, only for fault model 3.2 Metadata A copy of the original file format description is included in file_format.md, and is also available online here. A CSV file that includes information on each gridded seismicity location is also included (relm_gridded_region.csv).

本数据集为第三版加州统一地震破裂预报（Third Uniform California Earthquake Rupture Forecast, UCERF3）的配套数据文件，相关详细说明可参考https://doi.org/10.1785/0120130164。此类数据采用原始UCERF3断层系统解文件格式存储，该格式将二进制文件封装于ZIP压缩容器中。当前该格式正处于修订阶段，待新版更易用的格式定稿后，本数据集将发布更新版本。更多信息可参见https://opensha.org/File-Formats。

文件说明：
分支平均文件 此类文件包含分支平均的断层系统解，即依据各分支在最终模型中的权重，对所有UCERF3逻辑树分支的破裂属性（震级、滑动角、发震速率等）进行加权平均计算。这是该模型的最简版本，可用于快速近似计算平均灾害危险性。每个断层模型对应一个此类文件，且兼容UCERF3的时变版本。
branch_averaged_ucerf3_sol_FM3_1.zip：断层模型3.1的分支平均断层系统解文件
branch_averaged_ucerf3_sol_FM3_2.zip：断层模型3.2的分支平均断层系统解文件

完整模型（复合解） 此类文件包含完整的UCERF3逻辑树集，可用于提取单个逻辑树分支的数据（例如用于考虑全部认知不确定性的灾害危险性计算）。
full_ucerf3_compound_sol.zip：包含全部1440个与时间无关的逻辑树分支信息的完整复合解文件
full_ucerf3_compound_sol_with_individual_runs.zip：与上述文件内容一致，但额外包含每个逻辑树分支对应的10次模拟退火反演运行的速率数据（总计14400次反演）

真实平均解 另有一类分支平均解，即“真实平均”解可供使用。此类解与上述分支平均断层系统解类似，但当关键属性（滑动角、震级、断层面积）发生变化时，会为每个破裂生成独立副本。该方案保留了全部变异性，可通过最少的破裂集快速复现UCERF3的平均结果。OpenSHA中实现的MeanUCERF3地震破裂预报（Earthquake Rupture Forecast, ERF）即采用此类文件，同时支持用户通过各类近似方法进一步缩减破裂数量。注意：此类解无法兼容时变UCERF3计算，因为每个断层子区域可能存在多个实例，会造成各实例间的速率分配不均，进而导致复发更新模型计算的复发间隔出现错误。
true_mean_ucerf3_sol.zip：覆盖两种断层模型的真实平均断层系统解文件
true_mean_ucerf3_sol_FM3_1.zip：仅适用于断层模型3.1的真实平均断层系统解文件
true_mean_ucerf3_sol_FM3_2.zip：仅适用于断层模型3.2的真实平均断层系统解文件

元数据 本数据集包含原始文件格式说明的副本（file_format.md），也可在线获取。此外还包含一份CSV格式文件（relm_gridded_region.csv），其中记录了每个网格化地震活动性点位的相关信息。