EVA-8 was conducted on foot, and led 1.7km to Martian Squeeze ridge. The EVA started westward from the Hab to Radio Ridge Road, and then southward along the road to the area of interest.

During the EVA Dakota Sandstones were seen to overly Morrison Formation shales, as was expected. Within the Morrison Formation, channel deposits were observed on Martian Squeeze ridge and in somewhat lower stratigraphic units along Radio Ridge.

The channel deposits were composed of trough cross-bedded medium- to coarse grained sandstones, intercalated with pebble conglomerate units. The pebble conglomerates likely represent channel bar deposits within a braided river system.

The present geomorphology of Martian Squeeze ridge may be the trace of this ancient Jurassic river that flowed through the area approximately 100 million years ago. It is also conceivable that the Morrison shales are genetically related to these fluvial deposits, possibly as flood valley deposits, or, more likely, as distal delta deposits, which were occasionally disturbed as the delta mouth periodically switched channels. The sandstone and conglomerate channel deposits are much more resistant to mechanical and chemical weathering, and provide a protective cap on the more susceptible Morrison Formation shales.