Skip to Main Content
Book Chapter

Surface topography and internal strain variation in wide hot orogens from three-dimensional analogue and two-dimensional numerical vice models

By
Alexander R. Cruden
Alexander R. Cruden
Search for other works by this author on:
Mohammad H. B. Nasseri
Mohammad H. B. Nasseri
Search for other works by this author on:
Russell Pysklywec
Russell Pysklywec
Search for other works by this author on:
Published:
January 01, 2006

Abstract

The post-accretionary deformation of wide, hot orogens is characterized by pure-shear or transpressional shortening of relatively weak lithosphere (the orogen) between converging stronger blocks (the vice). We report on a series of analogue vice models and compare the resulting three-dimensional strain fields and surface topographics to equivalent two-dimensional numerical experiments. In the analogue models a rheologically stratified (frictional/viscous) weak orogenic lithosphere overlying a viscous asthenosphere is squeezed between converging strong lithospheric blocks. Ductile lower crust and mantle in the weak lithosphere is free to flow laterally, parallel to the orogen. The Argand number describes the model dynamics and strongly controls both the orogenic relief and the degree of lower crustal orogen parallel stretching in the analogue models. Cross sections of numerical and analogue experiments display consistent geometrics in which upper crustal deformation is characterized by upright folding compared to apparently decoupled horizontal strains in the lower crust. The relative buoyancy and degree of orogen parallel flow in the lower crust of the analogue models has a dramatic influence on three-dimensional strain fields and the kinematics of upper crustal curvilinear shear zones. The analogue and numerical results demonstrate the importance of three-dimensional effects in determining the structure of natural orogens and compare favourably to field and geophysical observations of large hot orogens in the geological record.

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