A reliable identification of the fault responsible for the magnitude 6.8 Al Haouz earthquake that struck Morocco on 8 September 2023 has so far been hampered by a lack of accurate tectonic analyses. Here we provide the first updated tectonic framework of the earthquake epicentral area based on original field data. We cast our results into the context of available geomorphological, thermochronological and geophysical constraints, and discuss the earthquake characteristics within the framework of competing tectonic models either based on asthenospheric upwelling or transpressional tectonics. We found that the Al Haouz earthquake was likely generated by rupture along a north-dipping high-angle fault, linking former fault planes belonging to an orogen-scale WSW-ESE transpressional shear zone. The geological evolution and seismotectonic structure of the region are largely governed by the oblique convergence of tectonic plates. The impact of asthenospheric upwelling, if any, remains limited and may only influence the geomorphological evolution of the Western High Atlas, but cannot explain the seismotectonic and geological features observed today at the surface, which are instead effects of transpressional tectonics.

中文翻译：

---

Mw 6.8 Al Haouz 地震（摩洛哥）的构造揭示了软流层上升流的次要作用


迄今为止，由于缺乏准确的构造分析，无法可靠地确定导致 2023 年 9 月 8 日袭击摩洛哥的 Al Haouz 地震的断层。在这里，我们提供了基于原始野外数据的第一个更新的地震震中区构造框架。我们将我们的结果置于可用的地貌、热年代学和地球物理约束的背景下，并在基于软流圈上升流或跨压构造的竞争构造模型的框架内讨论地震特征。我们发现，Al Haouz 地震可能是由沿北倾大角度断层的破裂引起的，该断层连接了属于造山带尺度 WSW-ESE 跨压剪切带的前断层平面。该地区的地质演化和地震构造在很大程度上受构造板块的斜向汇合控制。软流层上升流的影响（如果有的话）仍然有限，可能只影响西部高阿特拉斯的地貌演变，但无法解释今天在地表观察到的地震构造和地质特征，而这些特征是跨压构造的影响。