Skip to Main Content
Book Chapter

Influence of fault geometries and mechanical anisotropies on the growth and inversion of hanging-wall synclinal basins: insights from sandbox models and natural examples

By
O. Ferrer
O. Ferrer
Fault Dynamics Research Group, Department of Earth Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UKGeomodels Research Institute, Departament de Geodinàmica i Geofísica, Facultat de Geologia, Universitat de Barcelona, C/Martí Franquès s/n, 08028 Barcelona, Spain
Search for other works by this author on:
K. McClay
K. McClay
Fault Dynamics Research Group, Department of Earth Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
Search for other works by this author on:
N. C. Sellier
N. C. Sellier
Fault Dynamics Research Group, Department of Earth Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK
Search for other works by this author on:
Published:
January 01, 2017

Abstract:

Salt is mechanically weaker than other sedimentary rocks in rift basins. It commonly acts as a strain localizer, and decouples supra- and sub-salt deformation. In the rift basins discussed in this paper, sub-salt faults commonly form wide and deep ramp synclines controlled by the thickness and strength of the overlying salt section, as well as by the shapes of the extensional faults, and the magnitudes and slip rates along the faults. Upon inversion of these rift basins, the inherited extensional architectures, and particularly the continuity of the salt section, significantly controls the later contractional deformation.

This paper utilizes scaled sandbox models to analyse the interplay between sub-salt structures and supra-salt units during both extension and inversion. Series 1 experiments involved baseline models run using isotropic sand packs for simple and ramp-flat listric faults, as well as for simple planar and kinked planar faults. Series 2 experiments involved the same fault geometries but also included a pre-extension polymer layer to simulate salt in the stratigraphy. In these experiments, the polymer layer decoupled the extensional and contractional strains, and inhibited the upwards propagation of sub-polymer faults. In all Series 2 experiments, the extension produced a synclinal hanging-wall basin above the polymer layer as a result of polymer migration during the deformation. During inversion, the supra-polymer synclinal basin was uplifted, folded and detached above the polymer layer. Changes in thickness of the polymer layer during the inversion produced primary welds and these permitted the sub-polymer deformation to propagate upwards into the supra-salt layers.

The experimental results are compared with examples from the Parentis Basin (Bay of Biscay), the Broad Fourteens Basin (southern North Sea), the Feda Graben (central North Sea) and the Cameros Basin (Iberian Range, Spain).

You do not currently have access to this article.
Don't already have an account? Register

Figures & Tables

Contents

Geological Society, London, Special Publications

The Geometry and Growth of Normal Faults

C. Childs
C. Childs
University College Dublin, Ireland
Search for other works by this author on:
R. E. Holdsworth
R. E. Holdsworth
University of Durham, UK
Search for other works by this author on:
C. A.-L. Jackson
C. A.-L. Jackson
Imperial College, UK
Search for other works by this author on:
T. Manzocchi
T. Manzocchi
University College Dublin, Ireland
Search for other works by this author on:
J. J. Walsh
J. J. Walsh
University College Dublin, Ireland
Search for other works by this author on:
G. Yielding
G. Yielding
Badley Geoscience Ltd, UK
Search for other works by this author on:
Geological Society of London
Volume
439
ISBN electronic:
9781862399716
Publication date:
January 01, 2017

GeoRef

References

Related

A comprehensive resource of eBooks for researchers in the Earth Sciences

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal