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Presenting a rigorous treatment of the physical and mechanical basis for the modelling of sedimentary basins, this book supplies geoscientists with practical tools for creating their own models. It begins with a thorough grounding in properties of porous media, linear elasticity, continuum mechanics and rock compressibility. Chapters on heat flow, subsidence, rheology, flexure and gravity consider sedimentary basins in the context of the Earth's lithosphere, and the book concludes with coverage of pore space cementation, compaction and fluid flow. The volume introduces basic, state-of-the-art models and demonstrates how to reproduce results using tools like MATLAB and Octave. Main equations are derived from first principles, and their basic solutions obtained and then applied. Separate notes sections supply more technical details, and the text is illustrated throughout with real-world examples, applications and test exercises. This is an accessible introduction to quantitative modelling of basins for graduate students, researchers and oil industry professionals.

S U M M A R YThis article is about what influence continuous sedimentation has on the excess pressure, compaction and temperature in a sedimentary basin. We give an answer in terms of two dimensionless numbers 4) and A1 , which characterize the pressure and the temperature solution respectively. & = 1 is shown to define a transitional zone between excess pressured basins (with low compaction) and hydrostatic basins (with high compaction). The 4, parameter generalizes earlier results of Gibson. The most important physical parameter in A,) is the ratio between the permeability and the sedimentation rate. By means of &, we can quantify when 'high' sedimentation rates and 'low' permeability yield high excess pressures.This analysis is based on the porosity given by formulae of the form 4 = @(aps), where p s is the effective stress, and a is some scaling factor.In an analogous manner, A I = 1 defines a transitional zone when moving boundary effects become marked on the temperature. The most important parameter in AI is the ratio between a and the sedimentation rate.Simulation results are obtained by solving dimensionless pressure and temperature equations. The numerical pressure solution is compared with the exact solution given by Gibson, and is shown to be in excellent accordance.

A finite element based procedure is suggested for the modelling of hydraulic fracturing of heterogeneous rocks on a macroscopic scale. The scheme is based on the Biot-equations for the rock, and a finite element representation for the fracture pressure, where the fracture volume appears as fracture porosity. The fracture and the rock are represented unified on the same regular finite element grid. The numerical solutions of pressure and displacement are verified against exact 1D results. The 1D model also shows how the tension forces that open the fracture decreases as the gradient of the pore pressure decreases. The fracture criterion is based on the "strength" of bonds in the finite element grid. It is shown how this criterion scales with the grid size. It is assumed that fracturing happens instantaneously and that the fluid volume in the fracture is the same after a fracture event. The pressure drop that follows a fracture event is computed with a procedure that preserves the fluid volume in the fracture. The hydraulic fracturing procedure is demonstrated on a homogeneous and an inhomogeneous rock when fluid is injected at a constant rate by a well at the centre of the grid. A case of a homogeneous rock shows that a symmetric fracture develops around the well, where one bond breaks in each fracture event. A heterogeneous case shows the intermittent nature of the fracture process, where several bonds break in each fracture event.