A coupled THM model for a mini-basin sinking on salt

Peter Lovely, Marek Kacewicz, Tony Crook and Joshua Obradors (2018) Fully coupled poro-mechanical basin models for pressure and effective stress prediction, with application to a mini-basin in voluminous salt. In: SEG Technical Program Expanded Abstracts : 3221-3225.

In the publication discussed here ParaGeo is used to develop a thermos-hydro-mechanical (THM) model of a mini-basin in voluminous salt. The sediments are modelled with the SR4 model whereas the salt is modelled using a visco-plastic constitutive law.

In the paper it is shown how the model can successfully capture salt flow and evacuation from below the mini-basin depocenter to the mini-basin flanks, allowing the mini-basin to sink into the salt and generating some tectonic strain in the mini-basin flank due to the sub-horizontal push.

Several issues are approached in the paper:

1. Demonstrate the feasibility of developing coupled THM basin models for prediction of pore pressure and stress histories

2. Discuss the complexity in calibrating the models given the additional degrees of freedom from the displacement field compared to traditional basin modeling and the complex non-linear material properties

3. Present a workflow for developing and calibrating the coupled THM basin models with field data

4. Compare the solution with that of a traditional basin modelling software that considers vertical shear

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