Arsinoes and Pyrrhae Chaos are two adjacent chaotic terrains located east of Valles Marineris and west of Arabia Terra, on Mars. In this work, we produced a morpho‐stratigraphic map of the area, characterized by a volcanic bedrock disrupted into polygonal mesas and knobs (Chaotic Terrain Unit) and two nondisrupted units. The latter present a spectral variation, likely associated with hydrated minerals, and they are here interpreted as sedimentary units. The reconstructed geological history of the area starts with the emplacement of the basaltic bedrock, followed by the collapse that caused the formation of the chaotic terrains. Since evidences of volcano‐tectonic activity are widespread across the area (e.g., fissure vents/graben, radial and concentric systems of faults, y‐shaped conjunctions, lava flows, and pit chains), and an intricate system of lava conduits is hypothesized for the occurrence of such features, we propose the possibility that the whole collapse was caused primarily by volcano‐tectonic processes. In a late stage, after the end of the volcano‐tectonic activity, a lacustrine/evaporitic depositional environment could have set, with the deposition of the nondisrupted units. The hydrated minerals found in the periphery of the Chaos could be the result of hydrothermal alteration of the basaltic bedrock.

中文翻译：

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火星的Arsinoes和Pyrrhae混沌的构造-岩浆，沉积和热液史

Arsinoes和Pyrrhae Chaos是两个相邻的混沌地形，位于火星的Valles Marineris以东和Arab Terra的西部。在这项工作中，我们绘制了该地区的地貌地层图，其特征是火山基岩被破坏成多边形台地和凸起（混沌地形单元）和两个非破坏单元。后者表现出光谱变化，可能与水合矿物质有关，在这里它们被解释为沉积单位。该地区的重建地质历史始于玄武岩基岩的位置，然后是造成混乱地形形成的塌陷。由于火山构造活动的证据遍布整个地区（例如，裂隙喷口/深部，径向和同心的断层系统，Y形连接，熔岩流和矿坑链），并假设熔岩管道的复杂系统是由于这些特征的发生，我们提出了整个坍塌主要是由火山构造过程引起的可能性。在晚期，火山构造活动结束后，可能会形成湖相/蒸发沉积环境，并伴有未破坏单元的沉积。混沌外围发现的水合矿物可能是玄武质基岩热液蚀变的结果。