Abstract
The 4D seismic technology has been successfully applied on numerous brown fields in order to optimize reservoir production and recovery. This paper will describe how we incorporated the 4D seismic results in the geological model and illustrate some applications in reservoir management decisions, thereby mitigating drilling risks in Marlim deepwater turbidite heavy oil field. It will highlight the repositioning of numerous planned wells and the improvement in the history match using the updated geological model.
The Marlim giant field is located on the eastern Brazilian coast in water depths varying from 600 to 1200m (Figure 1). The reservoir is characterized by an unconsolidated sandstone turbidite related to the regressive mega sequence of the Brazilian eastern continental margin. It is the largest producing oilfield in Brazil (production peak: 615,000 bpd in 2002), with the original oil-in-place volume of 6.4 billion STB. Production started in 1991 and injection of water in 1994.
Three seismic surveys cover the Marlim Field. The first one acquired in 1986, the others in 1997 and 2005. The most recent survey was specifically acquired for reservoir characterization and monitoring purposes.