Correlation Between Graben Orientation, Channel Direction Change, and Tectonic Loading: The Elysium Province, Mars

Abstract

We have investigated the links between regional stress fields, the volcanic centers, rifts, graben, and channels in the NW region of the Elysium Province (Figures a and b) to determine whether the sequence of stress events occurring during province development can be derived from the morphologies of these features, and thus provide a sequence of development events, which is independent of surface dating techniques. Rift and graben geomorphology was mapped, and the neighboring relationships and orientation of individual graben were assessed to determine any spatial clustering or preferred orientation with regional or surface features capable of creating lithospheric flexure or tectonic stress within the study area. Crosscutting analysis determined a time ordered sequence of graben formation and these were related to volcanic centers or regional sources of stress. In addition, mapping showed that different channels share sections with similar shape and orientation, prompting our study of whether these channels, in tandem with the graben, were tectonically influenced during their development. The channel central axes were mapped and compared to identify common sequences of channel direction change. The time sequence of channel direction changes and the time‐ordered sequence of graben development were then compared. We have demonstrated a correlation between rift and graben direction with channel orientation suggesting a regional stress control from evolving volcanic centers. Overall we derive, for the first time, the temporal pattern of tectonic, volcanic, and channel evolution for the northwestern region of this major magmatic province on Mars.