A
color image of part of the Nilosyrtis Mensae region of Mars containing the
impact craters Antoniadi and Baldet (south to north) in the lower left corner;
north toward top. The scene shows heavily cratered highlands on the south
separated from the relatively smooth lowland plains on the northeast corner
by a belt of dissected terrain, containing flat-floored valleys, mesas,
buttes, and channels. The channels are (left to right) Auqakuh and Huo Hsing
Valles; Nili Fossae lie in lower right corner of image. |
 |
The
dissected terrain along the highlands/lowlands boundary consist of the flat-floored
valleys (mensae) and farther north the small, rounded hills of knobby terrain.
Flows on the mensa floors contain striae that run parallel to valley walls;
where valleys meet, the striae merge, similar to medial moraines on glaciers.
Terraces within the valley hills have been interpreted as either layer rocks
or wave terraces. The knobby terrain has been interpreted as remnants of
the old, densely cratered highland terrain perhaps eroded by mass wasting.
Auqakuh and Huo Hsing Valles and Nili Fossae are fretted channels and linear
depressions that likely formed by sapping and mass wasting along lines of
structural weakness. |
|