The outcrop is a well-sortedgravelconglomerate, containing well-rounded, smooth, abraded pebbles. Pebbles and gravel a few millimeters to centimeters across are embedded in amongst a finer, white matrix. This outcrop geology is strikingly similar to some terrestrial fluvial conglomerates. Around the rock are scattered well sorted loose gravel around 1 cm across, which are thought to be weathering out of the outcrop.
The rock has been interpreted as a cemented fluvialsediment, deposited by a "vigorously" flowing stream, probably between ankle and waist deep. This stream is part of an ancient alluvial fan, which descends from the steep terrain at the rim of Gale crater across its floor.