Ipubi Formation

Ipubi Formation
Stratigraphic range: Aptian-Albian ~113–111 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Outcrop of the Ipubi Formation underlying the Romualdo Formation
Type	Geological formation
Unit of	Santana Group
Underlies	Romualdo Formation
Overlies	Crato Formation
Thickness	up to 40 m (130 ft) average 15 m (49 ft)
Lithology
Primary	Shale, anhydrite
Other	Sandstone
Location
Coordinates	5°36′S 64°18′W / 5.6°S 64.3°W / -5.6; -64.3
Approximate paleocoordinates	9°12′S 34°00′W / 9.2°S 34.0°W / -9.2; -34.0
Region	Pernambuco, Piauí & Ceará
Country	Brazil
Extent	Araripe Basin
Type section
Named for	Ipubi
Named by	Beurlen
Year defined	1971
The Ipubi Formation is found in the southeastern part of the Araripe Basin, near Ipubi

The Ipubi Formation is the middle geological formation of the Santana Group, the middle part of the Araripe Group, in the Araripe Basin of northeastern Brazil. The formation is dated to the Aptian to Albian stages of the Early Cretaceous, unconformably overlying the Crato Formation and unconformably overlain by the Romualdo Formation, formerly known as the Romualdo Member of the Santana Formation. The averaging 15 metres (49 ft) thick Ipubi Formation comprises shales and sandstones in the lower section and evaporites in the upper part of the formation, deposited in a transgressive to highstand lacustrine environment in the Araripe rift basin.

The Ipubi Formation contains little fossils, apart from an indeterminate Pelomedusoides turtle, but contains high levels of TOC and the formation is identified as a potential target for shale gas development.