Searching for buried craters on Mars based on gravity potential field separation method

Abstract

There are many buried craters on Mars invisible in imaging or topographic data; however, the residual gravity anomaly separated from the Mars Bouguer gravity anomaly by minimum curvature separation method can reveal these buried craters. In our research, gravity separation results exposed 39 residual gravity anomaly highs (RGAHs), which may represent deeply buried impact craters with 300–500 ​km diameter. The RGAHs are widely distributed across the surface of Mars, but are especially concentrated in volcanic areas like Tharsis and Elysium, which indicates that there might be more craters buried in these regions. Older craters in volcanic regions were likely buried by subsequent volcanism coming from surrounding volcanoes, so the retention age of craters in all areas where RGAHs are located will be older than reported in the existing research based on topographic data alone. This study will help improve the chronological model of Mars. • The impact craters of Mars with diameter of 300–500 km appear central positive residual gravity anomalies. • The gravity separation results exposed 39 anomaly highs, that is inferred to be buried impact craters. • The most RGAHs are concentrated in volcanic areas just like Tharsis and Elysium.