Rib and trough features in an arctic lake

Location: Location uncertain, but thought to be in the vicinity of image 0071.

This image, taken at an altitude of about 300m, shows rib and trough structures developed preferentially adjacent to the shoreline developed on till and not on the shoreline developed on the sand and gravel at the upper left of the image. As do their terrestrial counterparts, mudboils, Rib-and-Trough Structures form only on deformable till surfaces. (note that the well-drained gravel-sand surface in the upper part of the image does not support vegetation and is scored by frost cracks that are usually only preserved in non-deformable sediments at this latitude). See image 0120 for further discussion.

Updated 04/29/2010 AW