Roncador production highlights Libra opportunity offshore Brazil
Roberto Ignacio da Silva
Hirdan Katarina de Medeiros Costa
Marilin Mariano dos Santos
Edmilson Moutinho dos Santos
Institute of Energy and Environment
University of Sao Paulo
Libra field in the Santos basin pre-salt has oil reserves estimated at 8 billion bbl, potentially increasing Brazil's total reserves by as much as 50%. Brazil's National Petroleum Agency (ANP) expects Libra to produce more than the five largest Brazilian oil fields combined: Roncador, Lula, Jubarte, Marlim Sul, and Marlim.1 2
This article compares the potential production of Libra with Brazil's current post-salt producer, Roncador in the Campos basin. It looks at the development history and production of Roncador to establish a similar curve for Libra.
Roncador, Libra fields
Brazil ranks 15th in the world with proven oil reserves of 15 billion bbl (Fig. 1). In Latin America, Brazil's reserves are second only to Venezuela.3 Roncador has been an important contributor to the country's reserves and currently provides 14% of Brazil's oil production.4 Libra could dwarf it.
Roncador lies in the northern part of the Campos basin about 125 km off Sao Tome Cape in Rio de Janeiro state. The field is in 1,500-2,000 m of water and covers about 132 sq km of the 7,000 sq km Campos.5
Roncador was discovered in October 1996 and has probable reserves of 3 billion bbl, producing 18-30° API crude.
Field development occurred in three phases. Phase 1 began in 1998 with field data acquisition and testing of new technologies. The field started producing in January 1999 at about 20,000 b/d through a floating production, storage, and offloading vessel (FPSO). Several subsea wells later were connected to a semisubmersible platform, boosting production to 84,000 b/d.5 6 7
Phase 2 included installation of a platform connected to 18 subsea wells and 11 water-injection wells. Work included laying about 220 km of flexible risers and flowlines, 161 km of umbilicals, and 83 km of jumper tie-backs. Further development featured 17 horizontal wells flowing to a second FPSO, bringing Roncador's total production to 350,000 b/d by 2009.5 6 7
Phase 3 included 11 add-on wells and seven water-injection wells producing 180,000 b/d through a third FPSO starting in 2011.
Libra is in the Santos basin about 170 km south of Rio de Janeiro in about 2,000 m of water. It covers about 1,549 of Santos' 15,000 sq km.8
Libra was discovered in October 2010 and it has prospective resources of about 8 billion bbl of 27° API crude. Libra's 6-year exploratory phase (Pilot 1) is under development. Pilot 1 includes drilling 17 exploratory wells; 8 production wells and 9 water-injections.
Production plans call for nine FPSOs connected to 92 production wells and 92 gas injection wells. This article uses an estimated flow rate of 25,000 b/d/well.8 9
Production volumes
Tables 1 and 2 present the key characteristics of Roncador and Libra that provide the basis for this article's analysis.
Roncador produced 918.2 million bbl 1999-2014. Production peaked in 2009 (Fig. 2).4 The Mar. 20, 2001, sinking of 84,000-b/d semisubmersible P-36, that took the lives of 11 Petroleo Brasiliero AS employees, sharply reduced production10
Overlapping Roncador's real production curve with the estimated production curve of Libra, reveals the size difference of the two fields (Fig. 3).
Libra shows a production peak of 1.28 million b/d in Year 12 of production, the same year Roncador reached its peak. Libra in Year 4 will surpass Roncador's peak. Libra's peak will exceed combined February 2015 production of Brazil's five biggest fields (Fig. 4).
Fig. 5 shows annual oil production curves, using real data from Roncador and estimated data from Libra.
In its seventh year of production, Libra will surpass the 918.2 million bbl Roncador produced in 17 years, reaching 1 billion bbl that year.
As early as 2016, there will be a reversal in the position of the two largest Brazilian basins with Santos overtaking Campos.
Libra has unique technical characteristics that could hinder the rate of production. The oil lies in 2,000 m of water and a further 5,000 m of sand, rock, and a shifting salt layer. The exploratory phase has generated a lot of data but not a full-scale view of what can be expected. These difficulties, however, are not new and can be overcome.
Bibliography
1. "Statistical Yearbook 2014," Agencia Nacional do Petroleo (ANP), September 2015.
2. "Bulletin of Petroleum and Natural Gas, February 2015.
3. "International Energy Statistics - Petroleum Reserves," US Energy Information Administration, October 201.
4. "Roncador Bulletin 2014," ANP, December 2014.
5. "Executive Summary of Roncador Field - Development Plan Approved by the Board," ANP, July 1, 2013.
6. Garcia, A.L., Bocos, M.D., and Mihaguti, M.K.,"Roncador Field Development: An Overview," presented to the Offshore Technology Conference, Houston, May 1-4, 2000.
7. Moreira, C.C., Pinto, F.J., Sanches, E.M., and Brack, M.,"Roncador Field Development: The Challenge of the Subsea Hardware Development," presented to the Offshore Technology Conference, Houston, May 1-4, 2000.
8. Lara, A.,"Libra PSC - Warming up the engines," presented to the Brazil-Texas Chamber of Commerce Offshore Breakfast, Houston, May 7, 2014.
9. "Review and Evaluation of Ten Selected Discoveries and Prospects in the Pre-Salt Play of Deepwater Santos Basin, Brazil," Gaffney, Cline & Associates, Sept. 15, 2010.
10. "Accident Analysis of the P-36 Platform," ANP, July 2001.
The authors
Roberto Ignacio da Silva ([email protected]) is pursuing an MS in energy policy at the University of Sao Paulo's Institutte of Energy and Environment. He holds a BS in mechanical technology from Sao Paulo State Technological College, a BS in mechanical engineering from Braz Cubas University, Mogilar, Brazil, and an MBA in engineering and management products and services from the University of Sao Paulo.
Hirdan Katarina de Medeiros Costa ([email protected]) is a lawyer and visiting professor at the University of Sao Paolo's Institute of Energy and Environment. She holds an MS in law from the University of Oklahoma College of Law, Norman. Costa also holds an MS in energy sciences and a PhD in energy policy from the University of Sao Paulo.
Marilin Mariano dos Santos ([email protected]) holds a BS in petroleum engineering from Mackenzie Presbyterian University, Sao Paulo, an MA in collective health, and a PhD in energy policy from the University of Sao Paulo.
Edmilson Moutinho dos Santos ([email protected]) is an associate professor at the Institute of Energy and the Environment at the University of Sao Paulo. He holds a BS in both economics and electrical engineering from the same institution. Santos holds MAs in energy management and policy from the University of Pennsylvania, Philadelphia, and energy-systems planning from the University of Campinas, Barao Geraldo, Brazil. He has a PhD in energy economics from the Petroleum Institute and Université de Bourgogne, Rueil-Malmaison Cedex, France.