Geological Characteristics of Floor‐Fractured Craters in the Central Noachis Terra, Mars: Implications for Post‐Noachian Habitable Environment

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Abstract Floor‐fractured craters (FFCs) are unique impact structures characterized by extensive fractures and uplifted floors, often associated with intrusive volcanic activity or potential aqueous processes. This study investigates a cluster of FFCs in central Noachis Terra, Mars, including Asimov, Maunder, and two unnamed craters to elucidate their geological characteristics and formation mechanisms. Using high‐resolution imagery, topographic data, and spectral analyses, we mapped three types of fractures and identified various landforms that may indicate past glacial activity, such as viscous flow features and polygonized textures, and candidate features that may indicate contemporary aqueous activity, such as gullies and recurring slope lineae. Mineralogical analyses revealed the presence of saponite and Mg‐ and Fe‐smectite within fractures, suggesting prolonged aqueous alteration. Age determination through crater counting indicates that the Maunder crater formed around 3.66 Ga (early Hesperian). We propose a hypothesis that the FFCs possibly originated from intrusive volcanism activated by the long‐lived structural inheritance of Hellas and Argyre basin impacts that retriggered by the young impact event of Maunder, with subsequent groundwater activity and glacial modification expanding the fractures. The existence of possible water/ice‐related landforms and aqueous minerals highlights the FFCs as hubs of hydrological activity and potential sites for past and present habitability. These results underscore the importance of FFCs as critical targets for future missions aiming to explore Mars' post‐Noachian climate transitions and habitable environment.

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