Nonlinear Viscoelastic Compaction in Sedimentary Basins

TL;DR

This paper develops a generalized viscoelastic compaction model for sedimentary basins, incorporating nonlinear rheological behaviour to better understand viscous compaction at greater depths.

Contribution

It introduces a Maxwell-type viscoelastic model with nonlinear characteristics, providing new insights into sediment compaction mechanisms.

Findings

Analysis of different nonlinear viscoelastic behaviours

Comparison of asymptotic solutions for compaction models

Enhanced understanding of pressure solution effects at depth

Abstract

In the mathematical modelling of sediment compaction and porous media flow, the rheological behaviour of sediments is typically modelled in terms of a nonlinear relationship between effective pressure $p_e$ and porosity $\phi$, that is $p_e=p_e(\phi)$. The compaction law is essentially a poroelastic one. However, viscous compaction due to pressure solution becomes important at larger depths and causes this relationship to become more akin to a viscous rheology. A generalised viscoelastic compaction model of Maxwell type is formulated, and different styles of nonlinear behaviour are asymptotically analysed and compared in this paper.