Together with the Loiano Sandstones, these marls constitute the Montepiano Formation. The Loiano Sandstones, whose name derives from the nearby locality where the extensive outcroppings are considered the official reference, outcrop from the foothills of Mount Termine to the Setta valley floor, where they are the subject of extensive mining activities serving the ceramics industry.
These light-colored rocks have a very coarse grain size and a high abundance of quartz. The sedimentation of these materials occurred during the Late Eocene in deep marine environments, where vast amounts of sediment were transported by special high-density currents. Similar to massive submarine landslides, these marine currents transported sediments that had previously been deposited in shallow sea areas, such as beaches and deltas, to sea floors far offshore.
The Loiano Sandstones are characterized by very thick, poorly distinguishable strata and by more strongly cemented layers, producing flat or rounded formations (cogoli), that protrude from the outcrops due to selective erosion.