Numerical modeling of land subsidence above faulted reservoirs by interface
elements
M. Ferronato, G. Gambolati, P. Teatini
Dept. Mathematical Methods and Models for Scientific
Applications, University of Padova, Padova, Italy
ABSTRACT
The stress variation induced by the development of underground reservoirs may activate pre-existing faults.
This may cause the opening or slip of the fracture surfaces with a possible impact on the expected land
subsidence due to the generation of mechanically weak points in the porous medium close to the producing
field. Since traditional finite element models are not able to simulate such deformations, special
''interface elements'' should be used. In the present communication, a class of elasto-plastic interface
elements, specifically designed to address the mechanical behavior of faults over a regional scale, is
developed and integrated into a traditional geomechanical poroelastic model. This model is used in a
realistic faulted reservoir to study the influence of fault deformations on land subsidence. It is shown
that the proposed interface elements can be simply incorporated into a traditional finite element model
improving the quality of the prediction made over faulted producing fields.
