Kirkwood Formation

Kirkwood Formation
Stratigraphic range: Berriasian-Hauterivian ~140–125 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Geological formation
Unit of	Uitenhage Group
Sub-units	Swartkops Member, Colchester Member, Bethelsdorp Member, Wood beds
Underlies	Sundays River Formation, Buffelskloof Formation
Overlies	Enon Formation
Thickness	up to 2,210 m (7,250 ft)
Lithology
Primary	Sandstone, claystone
Other	Mudstone, siltstone
Location
Coordinates	33°24′S 25°30′E / 33.4°S 25.5°E / -33.4; 25.5
Approximate paleocoordinates	45°00′S 11°30′W / 45.0°S 11.5°W / -45.0; -11.5
Region	Western & Eastern Cape
Country	South Africa
Type section
Named for	Kirkwood, Eastern Cape
Map showing extent of the Kirkwood Formation (green) in the Algoa and Gamtoos Basins

The Kirkwood Formation is a geological formation found in the Eastern and Western Cape provinces in South Africa. It is one of the four formations found within the Uitenhage Group of the Algoa Basin – its type locality – and in the neighbouring Gamtoos Basin. Outcrops of the Kirkwood are also found along the Worcester-Pletmos, Herbertsdale-Riversdale, Heidelberg-Mossel Bay, and Oudtshoorn-Gamtoos basin lines.^[1][2] At these basins the Kirkwood Formation underlies the Buffelskloof Formation and not the Sundays River Formation.^[3]