A study of anisotropic characteristics based on shear wave splitting (SWS) parameters (fast shear wave polarization and delay time) was carried out on 121 microearthquakes recorded by seismic arrays installed in Los Humeros Geothermal Field, Puebla, Mexico from 2011 to 2016. This analysis determined how both parameters seem to have been influenced by the geothermal field operation and by the spatial variations of the seismic sources with respect to the seismic array. There is a clear evidence of anisotropy since most of the SWS results show a main NW-SE polarization direction, which is not consistent with the maximum horizontal stress orientation in the region. The fast polarizations remained mostly constant for the analyzed period, keeping a preferential direction of NW-SE at the central-southern section of the study region, which in some cases follows the orientation of some proximal local faults. In the northern region, the fast polarizations appear uniform without following the orientations of the local faults. This preferential direction may be due to the shallow structures are being affected by the tectonism inhered from the basement, controlled in part by the Mexican fold and thrust belt whose main orientation is NW-SE and, to a lesser extent, by the pre-existing caldera ring faults.

Observations of mean delay times mostly range between 0.025 s and 0.07 s for all seismic stations analyzed, with some individual values reaching up to 0.15 s, but with a total average of 0.041 s for the period analyzed. The maximum anisotropy percentage found was 13.54%, and the variations allowed us to characterize the geothermal field in two main areas with high fracturing. Results show Los Humeros, Antigua, Los Conejos and Las Viboras faults, and other minor faults around them as the main conduits of permeable sources. However, the inferred Antigua and Malpaís faults may also be considered important areas.

Delay times δt and their respective error bars, showed an apparent decrease from 2014 to 2016, which may indicate a possible inverse correlation with an increase in fluid injection. However, the lack of data during 2013 and 2014 makes it difficult to robustly prove this hypothesis due to the change in station configuration.

基于2011年至2016年在墨西哥普埃布拉Los Humeros地热田安装的地震阵列记录的121次微地震，基于剪切波分裂（SWS）参数（快速剪切波极化和延迟时间）进行了各向异性特征研究。该分析确定了两个参数似乎受地热田间作业以及地震源相对于地震阵列的空间变化的影响。有明显的各向异性迹象，因为大多数SWS结果都显示出主要的NW-SE极化方向，这与该区域的最大水平应力方向不一致。在分析期间，快速极化几乎保持恒定，并在研究区域的中南部保持了西北偏南的优先方向，在某些情况下，它遵循一些近端局部断层的方向。在北部地区，快速极化似乎是均匀的，而没有遵循局部断层的方向。这种优先的方向可能是由于浅层结构受到地下室固有的构造作用的影响，部分受墨西哥褶皱和逆冲带控制，其主要方向是西北-东南，在较小程度上受先前存在的构造的控制。破火山口环断裂。

对于所有分析的地震台站，平均延迟时间的观测值大多在0.025 s和0.07 s之间，有些个体值达到0.15 s，但在分析期间的总平均值为0.041 s。发现的最大各向异性百分比为13.54％，并且这些变化使我们能够表征两个高压裂主要区域的地热场。结果表明，Los Humeros，Antigua，Los Conejos和Las Viboras断层以及它们周围的其他较小断层是渗透源的主要管道。但是，推断出的安提瓜和马尔帕斯的断层也可能被认为是重要的区域。

延迟时间δt和它们各自的误差线从2014年到2016年显示出明显的下降，这可能表明流体注入的增加可能与逆相关。但是，由于站配置的变化，2013年和2014年期间的数据不足，很难有力地证明这一假设。