Mechanical Compaction and Tectonic-Induced Deformation in Sedementary Basins: Modeling and Two-Dimensional Finite Element Analysis

Abstract

In addition to gravitational compaction, tectonic processes represent a major component of deformation in sedimentary basins during diagenesis. The aim of this contribution is to provide theoretical elements for the modeling of these phenomena, together with numerical aspects for basin simulators. A comprehensive constitutive model for the sediment material is first formulated within the framework of finite poroplasticity. Particular emphasis is put on the effects of large strains on the poromechanical properties of the sediment material. As regards the numerical assessment of sedimentary basin evolution, an original finite element procedure has been developed, specifically devised for simulating the processes of sediment accretion/erosion. After the numerical simulation of the whole phases of sediments deposition, the loading originating from tectonic sequences is simulated by imposing horizontal prescribed displacement at the lateral boundaries of the basin. Two-Dimensional (2D) finite element analyses are performed in either compressive tectonics situation.