Seismic Geomechanical Integration in the Brazilian Pre-Salt, Santos Basin

Abstract

Contents of this paper were reviewed by the Technical Committee of the 16 th International Congress of the Brazilian Geophysical Society and do not necessarily represent any position of the SBGf, its officers or members. Electronic reproduction or storage of any part of this paper for commercial purposes without the written consent of the Brazilian Geophysical Society is prohibited.

Integration of Seismic Data to Build Geomechanical Models for the Brazilian Pre-Salt Reservoirs – an Example in the Santos Basin

“…To estimate the geohazards in the post-salt section, the residual seismic pulse (wavelet) must be removed from the seismic data. Figure 8 illustrates the normalized wavelet frequency spectrum throughout the burial depth (Meneguim et al, 2019). We notice the narrowing of the frequency bandwidth mainly at high frequencies throughout the burial depth.…”

“…Besides these, there is also loss of fluid circulation in uncontrolled flow into fractured/high quality permo-porous rocks, such as sandstones and carbonates containing vugs and pipe sticking by soluble salts such as tachyhydrite, with creep behavior in the evaporitic section. These short-term events are potentially responsible for affecting the seabed facilitiy security, pipelines and platforms also influencing the project business value Toribio et al, 2017;Meneguim, 2019;Meneguim et al, 2019;Meneguim et al, 2021). Other geomechanical risks are associated with long-term reservoir´s production, as seabed subsidence, seal rock failure, post-salt fault/fracture reactivation, reservoir's compaction and well casing damages (Costa & Poiate Jr., 2009).…”

“…The 3 rd one was obtained from mechanical tests carried out in the Rock Test Lab of PUC (Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Gávea, RJ, Brazil, Department of Civil & Environmental Engineering). It was used roman travertine core samples as mechanical analogues of the good quality carbonate reservoirs since both have the same mineral composition: calcite and the available high porosity roman travertine with some dissolutions (Meneguim et al, 2019). It was observed a difference around 35% in the elasticity modulus estimation and close to 22% in the Poisson's ratio estimation when comparing the less rigid 3 rd equivalence with the most rigid 1 st one.…”

Building Integrated Geomechanical and Seismic Data Models for the Brazilian Pre-Salt Reservoirs Development, Examples in the Santos Basin

“…First of all, in order to estimate the geohazards making use of seismic data into post-salt section the residual seismic pulse (wavelet) must be removed from seismic data. Below, figure 1 illustrates the normalized wavelets frequency spectrum throughout burial depth (Meneguim et al, 2019) Figure 1: Normalized Wavelets Frequency Spectrum throughout the burial depth effect.…”

“…Besides, some important subsurface geologic hazards must be addressed in the offshore Santos Basin are short-term events and these may occur during the drilling and completion wells phases: shallow-water flow (SWF) sands and shallow gas sands into post-salt section, highly creep behaviour soluble salts at salt section and high pore-pressured rocks at the reservoir section. These short-term effects are potentially responsible for pipe sticking causing the loss of project profit and risks to seabed facilities (Teixeira et al, 2017;Toribio et al, 2017;Meneguim et al, 2019;Meneguim, 2019). Others geomechanical risks are associated to long-term reservoir´s production such as seabed subsidence, seal rock failure, post-salt faults/fractures reactivation and damage to wells casings (Costa & Poiate Jr., 2009).…”