The lower Tertiary formations of the Liguria-Piedmont basin (Italy) are characterized by epicontinental detrital deposits rich in clastic material. The biofacies generally have a littoral character. The general abundance of planktonic microfaunas suggests the existence of an open sea. Lower and middle Eocene sediments are absent in the area. The Oligocene was apparently affected by intense periods of erosion as indicated by local conglomeratic intervals. Variations in thickness of the Eocene-Oligocene section are related to submarine morphology and the hydrographic regime of the continent. Major tectonic disturbances occurred in the lower Miocene.