The formation consists of up to of white to pale pink
crossbedded quartz sandstone. It
unconformably overlies the
Sheep Pen Sandstone and is in turn overlain by the
Bell Ranch Formation. The Exeter Formation varies greatly in thickness, with the maximum thickness in
synclinal valleys of the underlying
Dockum Group and the formation being absent on some
anticlinal crests of the Dockum Group. The formation has long been thought to have formed in the eastern part of the
Entrada Formation dune sea and thus to be
correlative with the Entrada Formation, and
Spencer G. Lucas and coinvestigators recommended demoting the Exeter Sandstone to
member rank within the Entrada Formation. However, age control is poor on the Exeter Sandstone, and other investigators have retained the Exeter Sandstone at formation rank until the correlation becomes clearer. ==History of investigation==