The Random Formation is a rock unit in Newfoundland dating to the early Cambrian period, dominated by tidal quartz arenites deposited in a near-shore environment, but also incorporating intertidal and open-shelf deposits, including glauconitic and mud-cracked mudstones (now shales), and red channel sandstones.

[9][10] Its white arenitic sandstones are very distinctive, recognizable from their herringbone cross-stratification that denotes the influence of storm systems.

It was deposited in intertidal mud flats to subtidal setting, then (later) near the bottom of an open marine shelf.

[13] The trilobite-like trace fossils Rusophycus and Cruziana occur in the Random Formation, alongside a range of other ichnofossils including Diplocraterion, Paleodictyon, Scolicia, and Squamodictyon.

[13] Body fossils include the small shelly fauna Aldanella attleborensis assemblage.