Coupling time-lapse monitoring by satellite data and numerical geomechanical models
for reservoir management
P. Teatini, F. Comola, C. Janna, A. Lovison, M. Ferronato, G. Gambolati
M3E S.r.l., Padova, Italy, - DICEA, University of Padova, Italy
A. Tamburini, M. Minini, A. Ferretti
Tele-Rilevamento Europa TRE S.r.l, Milano, Italy
ABSTRACT
When large volumes of fluids are removed/injected from/into underground
formations (e.g. hydrocarbon and water extraction, CO2 storage, underground
gas storage, geothermal energy exploitation), monitoring of surface
deformation coupled to numerical modeling improves our understanding of
reservoir behaviour and helps implement a more effective reservoir management
and make more reliable predictions of future performance with obvious
economic benefits. The ability to accurately simulate surface displacements,
however, is often impaired by limited information on reservoir geometry,
waterdrive strength, and hydraulic and geomechanical parameters characterizing
the geological formations of interest. These uncertainties can be resolved,
or at least reduced, with the calibration of the geomechanical model against
the interferometry measurements by the use of metamodeling techniques, such
as Kriging, and effective global optimization (EGO) strategies. The proposed
methodology is applied to the Tengiz giant oil field, Kazakhstan.
SqueeSARTM on ENVISAT/RADARSAT-1 images acquired between 2004 and
2007 provided a set of high precision and high areal density subsidence
measurements. Only limited data, mainly taken from the web, is available to
the authors on the reservoir geometry, pore-pressure evolution, and
geomechanical properties of the pre-Caspian basin. Based on the previous
information a three-dimensional geomechanical model of the reservoir has been
developed by the elasto-plastic Finite Element (FE) GEPS3D simulator. EGO is
used to investigate the effect of the uncertainty on the geomechanical
response and to assess the best parameter configuration allowing for a
satisfactory reproduction of the ground displacements. Predicting the
deformation and stress fields, the model can be effectively used in its
forecasting potential to address the expected evolution of the land surface
movements, the possibile fault re-activation and/or fracture generation, and
the risk of well breaking depending on various development plans.
