The Crato Formation has often historically been considered the lowest member of the Santana Formation (or, alternatively, the Araripina Formation) of the Araripe Group, later redefined as the Romualdo Formation of the Santana Group.
The Crato Member is the product of a single phase, where complicated sequence of sediment strata reflect changeable conditions in the opening sea.
The age of this strata has been controversial, though most workers have agreed that it lies on or near the Aptian-Albian boundary, about 112 million years ago.

The extent of the Crato unit and its relationship to the Romualdo Formation had long been ill-defined.
It was not until a 2007 volume on the unit by Martill, Bechly and Loveridge that the Crato Formation was given a formal type locality, and was formally made a distinct formation separate from the Santana, which is about 10 Ma younger.
The Crato Formation is considered time equivalent with the Paracuru Formation.
The Crato Formation has often historically been considered the lowest member of the Santana Formation (or, alternatively, the Araripina Formation) of the Araripe Group, later redefined as the Romualdo Formation of the Santana Group. The Crato Member is the product of a single phase, where complicated sequence of sediment strata reflect changeable conditions in the opening sea. The age of this strata has been controversial, though most workers have agreed that it lies on or near the Aptian-Albian boundary, about 112 million years ago.
The extent of the Crato unit and its relationship to the Romualdo Formation had long been ill-defined. It was not until a 2007 volume on the unit by Martill, Bechly and Loveridge that the Crato Formation was given a formal type locality, and was formally made a distinct formation separate from the Santana, which is about 10 Ma younger. The Crato Formation is considered time equivalent with the Paracuru Formation.
Crato Formation