Many Small Interesting Ridges in Erythraea Fossa

These light-toned ridges are found in a large fracture located east of Holden Crater and form a curious box-like pattern.

A hair-line fracture runs along the axis of each ridge line . The overall pattern spans several hundred meters across and individual ridges are several meters wide. Scientists are not sure how they formed yet, but some possible explanations suggest that mineral-rich ground water flowed out of the hairline fractures and deposited minerals at or near the surface as the water evaporated.

In addition, these minerals may have formed a cement along the fractures, making these patterns more resistant to subsequent erosion by wind or other processes. The resulting cemented ridges then stand high above the surrounding plains.

Written by: Ginny Gulick (audio: Tre Gibbs)   (5 March 2014)

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Image: NASA/JPL/University of Arizona