Figure 2. A CTX mosaic of a section of the Bathys Planum region, where graben associated with the Stage 1 Claritas and Stage 3 Pavonis tectonic centers [Anderson et al., 2001] assume a stair-stepped or zigzagged morphology as they intersect the E-W curvilinear basement fabric. The inset map’s white box shows the location of this region in the mapping extent. Traces of the E-W basement structures can be identified indirectly due to downtrend alignments of stairsteps in the graben troughs. However, these traces sometimes manifest explicit surficial tectonic geomorphologies (see Figure 3). Instances of stairstepping and downtrend alignment are illustrated with yellow brackets. Image is centered near 115°W, 37°S.
This stair-stepping pattern is present where the graben intersect east-west trending lineaments (Figure 2). The graben are offset or deflected where the graben intersect, suggesting that the east-west trending structures influenced the development of the graben.
Additionally, downtrend of the graben-lineament intersections, depressions and hills have been identified adjacent to the lineament traces. These hills and depressions are consistent with pop-ups and pull-apart basins observed along strike-slip faults on Earth, suggesting that the lineaments are left-lateral strike-slip faults. In this study, the morphology and relative timing of these structures were examined and compared to other structures identified in this region.