Scamander Vallis
A color image of Scamander Vallis on Mars; north toward top. The scene shows heavily cratered highlands dissected by the slightly sinuous gully of Scamander Vallis. The channel begins by dissecting a steep slope of an impact crater wall and abruptly ends about 180 km north of the crater.
This image is a composite of Viking medium-resolution images in black and white and low-resolution images in color. The image extends from latitude 13 degrees N. to 19 degrees N. and from longitude 330 degrees to 332 degrees; Mercator projection.
The lack of tributaries, fairly straight path, and steep walls of the channel suggest spring sapping as a mode of origin. The abrupt termination may have resulted from burial by younger deposits or perhaps the flows percolated into the surface materials and continued underground.