Marlim is a giantBrazilianoil field located in the north-eastern part of theCampos Basin, about 110 km offshoreRio de Janeiro, in water depths ranging from 650 to 1,050 m. Marlim meansmarlin, in Portuguese.
Marlim was originally discovered by well in February 1985. The 75 m column was predominantly unconsolidatedsandstone, with apermeability as high as twodarcies. The discovery also showed high-gravity oil (17-21 degree API). At the time of discovery, the Marlim reservoir had an oil-in-place volume of about 9 billion barrels and an expectated 1.7 billion barrels of oil in total reserves.[1]
The Marlim field consists of a singleOligocene producing horizon ofsandstoneturbidites, with an area of 152 km2.[2]: 124 Reflection seismology in 1972 disclosed afaultedanticline and seismic amplitudebright spot, which was drilled by wildcat 1-RJS-219A in 1985 and discovered oil.[2]: 126 Thestratigraphy of the Campos Basin starts with theLower Cretaceous Lago FeiaFormation asource rock, followed by theAlbian Macae Formation consisting of shallow water carbonates overlain by late Albianshales,marls,calcilutites, andturbiditesandstones.[2]: 128 From this formation through most of theCenozoic, the Campos Formation was deposited, consisting of deep water turbiditic sandstones and shales, the main producers in theAlbacora and Marlim fields.[2]: 129 Finally, the basin was filled by the Ubatuba Formation, consisting of slope and shelf deposits.[2]: 129
