A Semiautomated Analysis of Displacement-To-Length Scaling of the Grabens Affecting Lunar Floor-Fractured Craters

Lunar floor-fractured craters are characterized by the occurrence of radial and concentric grabens, and while their formation mechanism was broadly studied in literature, the relationships between displacement and length of the faults, together with the fault growth, were never examined. We produced a semiautomated Python-based script able to analyze all the parameters required for this study: displacement, length, width of the grabens, and power law relationship between displacement and length. The results of our investigation, carried on in Komarov, Humboldt, and Atlas craters, showed a sublinear fault growth, suggesting that for some reason the increase in displacement is not linear with respect to length. This can result from the interplay of mechanical discontinuities related to the stratigraphy (which cause a vertical fault restriction, preventing the displacement from developing in depth), and to linkage phenomena. The D-max/L ratios that resulted from our analyses are higher than previously predicted for the Moon and appear more similar to the values observed on Earth. The slip distribution revealed different stages of fault interaction within the same crater, while the overall maturity of the grabens seems to be significantly high based on the observed symmetry of the grabens. Moreover, our code (public and accessible) can facilitate future works that aim to widen our knowledge about the lunar faults' growth, with all the implications that can improve our understanding of the faults' behavior.