Faulted craters as indicators for thrust motions on Mercury

Craters cross-cut by faults are used as markers to obtain fault geometric and kinematic properties. Assuming that the shape of these craters was originally circular, it is possible to measure the horizontal and vertical components of fault displacement as well as the slip trend. By applying trigonometric relations, slip plunge, displacement magnitude, fault true dip and fault rake can be derived from the observed values. An example application of this method on craters faulted by lobate scarps on Mercury shows that most of these inferred reverse faults have moderate oblique-slip trends. Moreover, the derived dips of thrusts vary over a wide range of angles. Some preliminary results in terms of fault rake compared with fault dip, strike and latitude are presented together with a pilot study to test and discriminate global tectonic models suggested for the evolution of Mercury. The possibility of estimating quantitative fault parameters through remotely sensed data provides significant assistance in the structural characterization of faults on planetary surfaces.