Role of faults and layer interfaces on the spatial variation of stress regimes in basins: inferences from numerical modelling

摘要: Abstract The spatial variation of the computed state stress is studied in a series numerically solved boundary-value problems basin-scale deformation. These numerical experiments illustrate simple situations decollement tectonism under compression. study focuses on local sedimentary overburden where major discontinuities such as large-scale faults and layer interfaces are present. states using either distinct element method or finite method. Classic elasto-plasticity laws used for behaviour continuum, modelled Coulomb contact surfaces. A geologic interpretation proposed to highlight role played by structural variations regime. models two-dimensional space assume plane strain, but full three-dimensional stress-strain constitutive relation used. Therefore, regime can be represented constructing contour map Wallace-Bott ratio. This technique, together with construction diagrams principal magnitude across model, enables us rapidly examine stress-field pattern further discuss deformation modes faulting fracturing, which may take place at small scale. We have found that tensor good agreement common brittle deformations foreland thrust systems. demonstrate how presence interface difference mechanical properties formation lithology strongly affect space. modelling approach has important issues when interpreting well tests gain access in-situ stresses.