Skip to Main Content
Book Chapter

Anisotropy of magnetic susceptibility (AMS) records synsedimentary deformation kinematics at Pico del Aguila anticline, Pyrenees, Spain

By
David Anastasio
David Anastasio
Department of Earth and Environmental Sciences, Lehigh University, Bethlehem, PA, United States
Search for other works by this author on:
Josep M. Parés
Josep M. Parés
Paleomagnetism Laboratory, Cenieh, Burgos, Spain
Search for other works by this author on:
Kenneth P. Kodama
Kenneth P. Kodama
Department of Earth and Environmental Sciences, Lehigh University, Bethlehem, PA, United States
Search for other works by this author on:
Joanna Troy
Joanna Troy
Department of Earth and Environmental Sciences, Lehigh University, Bethlehem, PA, United States
Search for other works by this author on:
Emilio L. Pueyo
Emilio L. Pueyo
Instituto Geológico y Minero de España, Unidad de Zaragoza, Spain
Search for other works by this author on:
Published:
January 01, 2016

Abstract

Pico del Aguila anticline is a transverse décollement fold located at the Pyrenean thrust front. The anticline is a synsedimentary structure buried during growth by delta front mudstones and sands of the Eocene Arguis and Belsué-Atares formations. Both the anisotropy of magnetic susceptibility measured at 77 K and 294 K and the anisotropy of anhysteretic remanence show that susceptibility is dominated by paramagnetic clay minerals and can be used as a proxy for depositional and tectonic fabric orientations. In general, the maximum and intermediate principal susceptibilities (k1 and k2) of the AMS lie in bedding and the minimum principal susceptibility (k3) is oriented nearly normal to bedding. Layer-parallel shortening (LPS) produced a c. north–south-trending magnetic intersection lineation in bedding on anticline limbs and in the adjacent Belsué and Arguis synclines by deforming the depositional and diagenetic compaction fabric. The degree of magnetic anisotropy is higher along axial surfaces than on limbs. At the anticline hinge, oblate magnetic ellipsoids with an east–west-aligned lineation and a bedding-parallel magnetic foliation demonstrate the overprinting of the LPS magnetic fabric during the emplacement of the underlying thrust sheet. AMS data record fold kinematics characterized by constant-length limb rotation about pinned hinges and are compatible with kinematics recorded by growth strata geometries. This study emphasizes that AMS is a very sensitive measure of depositional, compaction and tectonic fabrics in marine clastic rocks in the diagenetic realm.

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

Figures & Tables

Contents

Geological Society, London, Special Publications

Palaeomagnetism in Fold and Thrust Belts: New Perspectives

E. L. Pueyo
E. L. Pueyo
IGME, Spain
Search for other works by this author on:
F. Cifelli
F. Cifelli
Università degli Studi Roma TRE, Italy
Search for other works by this author on:
A. J. Sussman
A. J. Sussman
Los Alamos National Laboratory, USA
Search for other works by this author on:
B. Oliva-Urcia
B. Oliva-Urcia
Universidad Autónoma de Madrid, Spain
Search for other works by this author on:
Geological Society of London
Volume
425
ISBN electronic:
9781862399570
Publication date:
January 01, 2016

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