Permanent ground offsets, constituting a prime dataset for constraining final fault‐slip distributions, may not be recovered straightforwardly by double integration of near‐field accelerograms due to tilt and other distorting effects. Clearly, if a way could be found to recover permanent ground offsets from acceleration records, then static datasets would be enlarged, and thus the resolution of fault‐slip inversions would be enhanced. Here, we introduce a new approach for extracting permanent offsets from near‐field strong‐motion accelerograms. The main advantage of the new approach with respect to previous ones is that it corrects for source time functions of any level of complexity. Its main novelty is the addition of a constraint on the slope of the ground velocity spectra at long periods. We validated the new scheme using collocated accelerograms and Global Navigation Satellite Systems (GNSS) records of the 2011 Mw 9 Tohoku‐Oki earthquake. We find a good agreement between accelerogram‐based and GNSS‐based ground offsets over a range of 0.1–5 m. To improve the spatial coverage of permanent ground offsets associated with the 2004 Parkfield earthquake, near‐field accelerograms were baseline corrected using the new scheme. Static slip inversion of the combined GNSS‐based and accelerogram‐based ground displacements indicates appreciable seismic moment release south of the epicenter, about 5 km into the Cholame section of the San Andreas fault. We conclude that the strong shaking observed to the south of the epicenter is directly related to the slip in that area and is not the result of local amplification.

中文翻译：

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从近场加速度图中自动提取永久性地面偏移：算法，验证和在2004年Parkfield地震中的应用

永久地面偏移量构成了约束最终断层滑动分布的主要数据集，由于倾斜和其他失真效应，近场加速图的双重积分可能无法直接恢复。显然，如果找到一种从加速度记录中恢复永久性地面偏移的方法，那么静态数据集将得到扩大，从而断层滑动反转的分辨率将得到提高。在这里，我们介绍了一种从近场强运动加速度图中提取永久偏移的新方法。与以前的方法相比，新方法的主要优点在于，它可以校正任何复杂程度的源时间函数。它的主要新颖之处在于在长时间内对地面速度谱的斜率增加了限制。我们使用并列的加速度计和2011年9月东北冲木地震的全球导航卫星系统（GNSS）记录验证了新方案。我们发现在0.1-5 m范围内，基于加速度计和基于GNSS的地面偏移量之间存在良好的一致性。为了改善与2004年Parkfield地震有关的永久性地面偏移的空间覆盖范围，使用新方案对近场加速度图进行了基线校正。基于GNSS和基于加速度计的组合地面位移的静态滑移反演表明震中以南有明显的地震矩释放，距圣安德烈亚斯断层Cholame段约5 km。我们得出的结论是，震中南部观察到的强烈震动与该地区的滑移直接相关，而不是局部放大的结果。