Production from offshore pre-salt oil deposits has increased Brazil’s oil production

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Production from offshore pre-salt oil deposits has increased Brazil’s oil production
https://www.eia.gov/todayinenergy/detail.php?id=34132
DECEMBER 14, 2017




Brazil has produced 3.3 million barrels per day (b/d) of petroleum and other liquids so far in 2017, according to data through August, up from 3.2 million b/d in 2016, making it the ninth-largest producer of petroleum and other liquids in the world. Production of crude oil in Brazil increased in recent years as producers targeted large, offshore, pre-salt oil deposits. Brazil’s pre-salt oil production in 2016 reached a record 1.02 million b/d, surpassing the 2015 production level by 33%.

Pre-salt oil deposits are located offshore under deep, thick layers of rock and salt and require substantial investment to extract. The depths and pressures involved in pre-salt production present significant technical hurdles. Despite these challenges, however, pre-salt crude oil production in Brazil has increased significantly since it began in 2009.

Pre-salt resources were first discovered in Brazil’s offshore Santos Basin in 2005 by state-controlled Petrobras, the dominant participant in Brazil’s oil sector. Further exploration in the Santos, Campos, and Espirito Santo basins revealed an estimated 5 billion to 8 billion barrels of oil equivalent in a pre-salt zone 18,000 feet below the ocean surface.



With the exception of the Libra field, all pre-salt areas currently under development were granted to Petrobras without competition. The Libra field was the first to be auctioned under Brazil's new production-sharing model, and it is operated by Petrobras (40%) as part of the international consortium whose other partners are Total (20%), Shell (20%), and Chinese national oil companies China National Offshore Oil Corporation (10%) and China National Petroleum Corporation (10%).

The Libra field—the largest pre-salt oil discovery to date in the Santos Basin—began producing for the first time in November 2017. The field is located approximately 106 miles off the coast of Rio de Janeiro in water depths up to 11,500 feet. According to Brazil’s National Agency of Petroleum, Natural Gas, and Biofuels (ANP), the Libra field is estimated to hold 8 billion to 12 billion barrels of recoverable reserves.

Using a floating production, storage, and offloading vessel (FPSO), early production from Libra has been about 50,000 b/d. Development of the field is expected to continue in the 2020s with the deployment of another FPSO that has a production capacity of 150,000 b/d. ANP estimates that peak production at Libra could eventually reach 1.4 million b/d.

More information about Brazil’s energy sector is available in EIA’s Brazil Country Analysis Brief.

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Understand how the pre-salt was formed
http://www.petrobras.com.br/en/our-activities/performance-areas/oil-and-gas-exploration-and-production/pre-salt/



The Pre-salt is a sequence of sedimentary rocks formed more than 100 million years ago in the geographic space created by the separation of the ancient Continent of Gondwana. More specifically, it was formed by the separation of the current American and African continents, a process that started about 150 million years ago. Initially, great depressions were formed between the two continents, giving rise to large lakes. Over millions of years, the rocks that would give rise to the pre-salt region's oil were deposited there. Since all the rivers on the continents that separated flew to the lower regions, large amounts of organic matter were deposited there.

As the continents strayed, the organic materials accumulating in the new space were being covered by the waters of the Atlantic Ocean, which was then forming. That was when the layer of salt that currently reaches 2000 meters in thickness started being formed. This layer was deposited on the accumulated organic matter, holding it there for millions of years until thermochemical processes turned it into hydrocarbons (oil and gas).

In the current Brazilian exploratory context, the possibility of the occurrence of the set of rocks with potential to generate and accumulate oil in the pre-salt layer is in the province called the pre-salt, an area measuring approximately 800 km in length and 200 km in width, off the coast between the states of Santa Catarina and Espírito Santo.

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[IsailedawayfromFR]

Isn't this interesting stuff.  Geology is a fascinating field even if just a hobby and not a career.  It makes even a weekend drive turn into an adventure.