The Lapa oil field is a deepwater oil field in the pre-salt Guaratiba Group of the South Atlantic Santos Basin, 270 kilometres (170 mi) off the coast of São Paulo, Brazil.

The field was taken into production in December 2016 and is operated by Petrobras with BG and Repsol-Sinopec as partners.

It was speculated and released to the press by a spokesman of the Brazilian national petroleum agency, Agência Nacional do Petróleo (ANP), that "the field could contain reserves as large as 33 billion barrels [5.2 billion cubic metres]" of oil,[1] which would make it the biggest discovery in 30 years and one of the largest oil fields worldwide, the biggest outside of the Middle East, surpassing the Cantarell Complex of the Gulf of Mexico and the Bolivar Coastal Field of the Venezuelan oil belt.

[2] The excitement about Carioca has been mentioned as an example of "oil fever" in the exploration of the Brazilian deepwater pre-salt plays.

[3] The reservoir of the Lapa oil field is the pre-salt Guaratiba Group, a Hauterivian to Aptian sequence of limestones and clastic sediments of which the microbialite, stromatolite-like limestone hosts vast amounts of oil.