Integrated 3D geomechanical modelling for deep subsurface damage. A case study of tectonic and man induced damages in the eastern Netherlands
conference paper
Current advances in finite element computer codes and increase in computer power theoretically allow quantitative modelling of the geomechanical effects of hydrocarbon depletion from reservoirs. Here we show that it is technically possible to incorporate the full complexity of the 3D geological structure of a reservoir including faults into geomechanical models. In the workflow GOCAD is used for the structural modelling, integrated with DIANA for the geomechanical calculations. A case study on the Roswinkel gas field in the eastern Netherlands illustrates the working methodology. The case study clearly shows the strong dependency of gas depletion deformation effects on the prevailing tectonic stress field. Our models for gas depletion predict a stabilization of the stress field (further away from failure) for reservoirs in compressive and strike-slip regimes. On the other hand extensional stress regimes will result in failure of the reservoir, in agreement with observed earthquakes, provided that (a) the reservoir material or existing faults are weak and (b) the state of stress is close to failure of the material. The Roswinkel field, which is marked by a high abundance of earthquakes occurring after gas depletion started, is therefore most likely marked by an extensional tectonic regime and by geomechanically weak rock or pre-existing faults. According to base Tertiary fault displacements and the World Stress
Topics
TNO Identifier
330172
ISSN
0305-8719
Publisher
Geological Society of London
Source title
New Insights into Structural Interpretation and Modelling : Special Publications
Pages
313-328
Files
To receive the publication files, please send an e-mail request to TNO Repository.