The Horlick Formation is a fossiliferous, predominantly
marine succession of interbedded sandstone and mudstone
that crops out along a prominent escarpment in the Ohio
Range. The formation buries a relatively level wave-cut
platform eroded across a basement granitoid, and is
nowhere more than 56 m thick due to subsequent
Permo–Carboniferous glacial erosion.
The sediments have been described in terms of nine
lithofacies (Bradshaw & McCartan 1983, McCartan &
Bradshaw 1987), that were renamed in conjunction with the
establishment of six ichnocoenoses (Bradshaw et al. 2002).
An abundant but relatively limited shelly fauna was
described by Doumani et al. 1965 and Bradshaw &
McCartan 1991.
The six ichnocoenoses within the Horlick Formation have
been used in palaeoenvironmental interpretations
(Bradshaw et al. 2002). Catenarichnus is an important
element and name bearer for one of these ichnocoenoses.
Detailed descriptions of the remaining ichnofauna will be
described in a separate paper.