Automated Depth/Diameter and Topographic-Cross-Profile Measurements Based on GT-57633 Catalogue of Martian Impact Craters and MOLA Data

The methods for the automated depth/ diameter and topographic-cross-profile measurements were applied to the newly available GT-57633 catalogue and MOLA data. The result is improved insight into the global geometric properties of Martian craters. Introduction: Martian impact crater properties differ appreciably from those on the Moon, and reflect both gravitational and regional target properties [1]. Thanks to the availability of MOLA data, numerous diameter (D) dependent impact crater parameters and relationships can be measured [2], such as depth (d), rim height, central peak height, central peak diameter, cavity shape, etc. For numerous studies d/D relationship [3,4] as well as topographic-cross-profile [2,5] is important. However, while different authors generally agree that Eq. (1) is a good approximation for relationship between d and D for fresh and pristine impact craters, large variety of α and β has been reported. As given in [1], α=0.26 and β=0.67 for D < 7km (simple craters), while α=0.36 and β=0.49 for 7km < D < 110km (complex craters). While in [2] the same values are reported for α and β for large craters, reported values for small craters are α=0.21 and β=0.81. Reported values in [6] for large craters are α=0.44 and β=0.38. In [7], reported values for the global average of fresh complex craters are α=0.37 and β=0.46, while significantly different values α=0.25 and β=0.82 are reported for the deepest of fresh complex craters. For complex craters (12km < D < 49km) values reported in [8] are α=0.381 and β=0.52 for pristine craters and α=0.315 and β=0.52 for fresh craters. To obtain results that represent large number of craters and global trends, the measurements of a large number of craters are required. Significant efforts have already been invested in this direction to provide automated measurements [9,10]. In our previous work, for evaluation of Crater Detection Algorithms (CDAs) [11], the GT-57633 catalogue of Martian impact craters was assembled [12]. In this work, we will present automated depth/diameter and crossprofile measurements applied to these craters. β α D d ⋅ = (1)