Guarujá Formation
Guarujá Formation | |
---|---|
Stratigraphic range: Early Albian ~ | |
Type | Geological formation |
Unit of | Camburi Group |
Underlies | Itajaí-Açu Fm., Juréia Fm. |
Overlies | Ariri Formation |
Thickness | up to 2,500 m (8,200 ft) |
Lithology | |
Primary | Limestone |
Other | Marl |
Location | |
Coordinates | 26°6′S 43°43′W / 26.100°S 43.717°W |
Region | Santos Basin, South Atlantic |
Country | Brazil |
Type section | |
Named for | Guarujá |
Location of the Santos Basin |
The Guarujá Formation (Portuguese: Formacão Guarujá) is a geological formation of the Santos Basin offshore of the Brazilian states of Rio de Janeiro, São Paulo, Paraná and Santa Catarina. The predominantly calcarenite formation with marls dates to the Early Cretaceous period; Early Albian epoch and has a maximum thickness of 2,500 metres (8,200 ft). The formation is the second-most important post-salt reservoir rock of the Santos Basin.
Etymology
The formation is named after the city of Guarujá, São Paulo.
Description
The Guarujá Formation is 832 to 2,500 metres (2,730 to 8,202 ft) thick,[1] and consists of oolitic calcarenites, which laterally grade to greyish ochre and brownish grey calcilutites and grey marls. These facies are interbedded with the alluvial clastics of the Florianópolis Formation. The Guarujá name is restricted to the lowest limestone intercalation, previously named Lower Guarujá by Ojeda and Ahranha in Pereira and Feijó (1994). The microfacies indicate a tidal flat to shallow lagoon and open carbonate platform depositional environment. The age based on planktonic foraminifera and pollen is Early Albian.[2]
Petroleum geology
The formation is the second-most important post-salt reservoir rock of the Santos Basin,[3] after the Itajaí-Açu Formation.[4][5]
Field | Year | Operator | Reserves (in place, million barrels) | Reserves (in place, million m3) | Notes |
---|---|---|---|---|---|
Cavalo Marinho | 2001 | Petrobras | 25.04 | 3.981 | |
Caravela | 1992 | Petrobras | 48.81 | 7.760 | |
Caravela Sul | 1991 | Petrobras | 5 | 0.79 | |
Coral | 1990 | Petrobras | 22.57 | 3.588 | |
Estrela do Mar | 1990 | Petrobras | 15.16 | 2.410 | |
Tubarão | 1988 | Petrobras | 30 | 4.8 |
See also
References
- ^ Kiang Chang et al., 2008, p.32
- ^ Clemente, 2013, p.22
- ^ Contreras, 2011, p.34
- ^ a b c d e f "Santos Basin Fields". Archived from the original on 2017-09-07. Retrieved 2017-09-07.
- ^ Vieira, 2007, p.9
- ^ Juarez, 2013, p.14
- ^ ANP Yearbook, 2014, p.30
- ^ Coral Field: Case History in Oil Producing Albian Carbonates in Santos Basin, Brazil
- ^ Estrela do Mar, Cavalo Marinho oil output by 2007
- ^ Juarez, 2013, p.11
Bibliography
- Geologic formations of Brazil
- Santos Basin
- Cretaceous Brazil
- Lower Cretaceous Series of South America
- Albian Stage
- Limestone formations
- Marl formations
- Tidal deposits
- Lagoonal deposits
- Shallow marine deposits
- Reservoir rock formations
- Petroleum in Brazil
- Geography of Paraná (state)
- Geography of Rio de Janeiro (state)
- Geography of Santa Catarina (state)
- Geography of São Paulo (state)