The sediments of the formation were deposited during the Late Oligocene and Early Miocene epochs.

The formations lower sections are made up of conglomerate, then successions of sandstone, tuff and mudstone rich in organic material follows.

The formation indicates that sedimentation occurred in an estuarine (paralic) and other non-marine (continental) environments.

It contains fossils of the following genera: Mytilus, Cardium and Turritella.

Stratigraphically it overlies the Bahía Mansa Metamorphic Complex and underlies the Miocene Santo Domingo Formation.