Marine fossils are very abundant in the marl.
On the island of Andros there is an extremely fine white marl almost resembling a chalky ooze.
The oak grows most luxuriantly on deep strong clays, calcareous marl or stiff loam, but will flourish in nearly any deep well-drained soil, excepting peat or loose sand; in marshy or moist places the tree may grow well for a time, but the timber is rarely sound; on hard rocky ground and exposed hillsides.
The Cambridgeshire coprolites are believed to be derived from deposits of Gault age; they are obtained by washing from a stratum about a foot thick, resting on the Gault, at the base of the Chalk Marl, and probably homotaxeous with the Chloritic Marl.
The Chloritic Marl in the Wealden district furnishes much phosphatic material, which has been extensively worked at Froyle.