Definition of facies distribution in a pre-salt reservoir using mathematical methods

• Grant number: 20/02128-8
• Support type: Scholarships in Brazil - Master
• Effective date (Start): May 01, 2020
• Effective date (End): February 28, 2022
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Cooperation agreement: Equinor (former Statoil)
• Principal Investigator: Alexandre Campane Vidal
• Grantee: Marília Molina Camargo
• Home Institution: Centro de Estudos do Petróleo (CEPETRO). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 17/15736-3 - Engineering Research Centre in Reservoir and Production Management, AP.PCPE

Abstract

The characterization of facies is essential for reservoir modeling. However, this is a process that depends on many variables, with errors and associated noise that interfere on interpretation. This becomes critical in reservoirs with high geological complexity, such as the pre-salt reservoirs. The pre-salt reservoirs consist of cyclic distribution of various types of carbonates and Mg-clays of in a lacustrine environment in highly alkaline settings that control facies development. The typically subdecametre scale symmetrical and asymmetrical cyclothems exhibit three main components: mud-grade laminated carbonates, millimetre-diameter spherulites with evidence of having been in a matrix of Mg-silicates, and millimetre-centimetre calcitic shrub-like growths. This work proposes to analyze the electrofacies of the geophysical dataset of a pre-salt reservoir, in order to identify the lithologies related to reservoir rocks. The choice to specifically study reservoir lithologies is due to its importance in building the geological model of the reservoir, whose main information sources are the data from well logs. The definition of the quality of the reservoir rock, variables such as porosity, permeability and water saturation will be defined, as well as the identification of the different lithological types. (AU)