Skip to Main Content
Book Chapter

Multiple faults in ductile simple shear: analogue models of flanking structure systems

By
Ulrike Exner
Ulrike Exner
Search for other works by this author on:
Bernhard Grasemann
Bernhard Grasemann
Search for other works by this author on:
Neil S. Mancktelow
Neil S. Mancktelow
Search for other works by this author on:
Published:
January 01, 2006

Abstract

Rotational behaviour and deformation around multiple faults was investigated in analogue experiments using a linear viscous matrix material under simple shear boundary conditions. Previous analogue and numerical studies have shown that, for single faults, characteristic deformation geometries are produced in initially straight marker lines parallel to the shear zone boundary (flanking structures). Observations from several natural shear zones suggest that not only single faults, but often several parallel or conjugate fault planes are subjected to progressive shear resulting in distinctive deflection geometries. If the distance between faults is on the order of their length, or less, then the perturbation flow fields interfere and coalescence, and finite deflection structures develop that are distinctly different from those around single fractures. In particular, coeval contractional and extensional geometries may develop across conjugate faults, although for bulk simple shear the total length of marker lines parallel to the shear zone boundary cannot change. This advises caution in inferring shear-zone parallel contraction or extension from secondary slip surfaces. In contrast to single flanking structures, conjugate flanking structure systems occurring in natural shear zones are reliable shear sense indicators due to their triclinic symmetry.

You do not currently have access to this article.

Figures & Tables

Contents

Geological Society, London, Special Publications

Analogue and Numerical Modelling of Crustal-Scale Processes

S. J. H. Buiter
S. J. H. Buiter
Geological Survey of Norway, Trondheim, Norway
Search for other works by this author on:
G. Schreurs
G. Schreurs
University of Bern, Switzerland
Search for other works by this author on:
Geological Society of London
Volume
253
ISBN electronic:
9781862395015
Publication date:
January 01, 2006

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal