Skip to Main Content
Book Chapter

Tectonic and magmatic evolution of the mantle lithosphere during the rifting stages of a fossil slow–ultraslow spreading basin: insights from the Erro–Tobbio peridotite (Voltri Massif, NW Italy)

By
Matteo Padovano
Matteo Padovano
Via XXV Aprile 37, 16012, Bargagli, Genova, Italy
Search for other works by this author on:
Giovanni B. Piccardo
Giovanni B. Piccardo
Via Sturla 33/4, 16131 Genova, Italy
Search for other works by this author on:
Reinoud L. M. Vissers
Reinoud L. M. Vissers
Department of Earth Sciences, Utrecht University, PO Box 80021, 3508TA Utrecht, The Netherlands
Search for other works by this author on:
Published:
January 01, 2015

Abstract

We investigate the structural, petrological and compositional features recorded by strongly deformed and melt-percolated Erro–Tobbio peridotites (Voltri Massif, Ligurian Alps, NW Italy), in order to demonstrate that the processes of shear-zone formation and melt percolation are intimately linked by a positive feedback. We focus on spinel and plagioclase peridotites, and extensional shear zones that underwent infiltration by upwelling asthenospheric melts. Shear and porosity bands, which developed during extension prior to melt infiltration, represent important structural and rheological pathways to facilitate and enhance melt infiltration into the extending lithosphere and the ascent of such melts to shallower levels.

Our results lend strong support to numerical models addressing the physical processes underlying extensional systems. These show that, in the case of slow–ultraslow continental extension and the subsequent formation of slow–ultraslow spreading oceans, porosity and shear-localization bands may develop in a previously unstructured lithosphere, prior to melt infiltration. Our studies on the Erro–Tobbio peridotites allow a model for the inception of continental extension and rifting to drifting of slow–ultraslow spreading oceans to be proposed. We suggest that integrated studies of on-land peridotites, coupled with geophysical–structural results from modern oceans, may provide clues to the geodynamic processes governing continental extension and passive rifting.

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

Figures & Tables

Contents

Geological Society, London, Special Publications

Sedimentary Basins and Crustal Processes at Continental Margins: From Modern Hyper-extended Margins to Deformed Ancient Analogues

G. M. Gibson
G. M. Gibson
Australian National University, Australia
Search for other works by this author on:
F. Roure
F. Roure
IFP Energies Nouvelles, France
Search for other works by this author on:
G. Manatschal
G. Manatschal
Université de Strasbourg, France
Search for other works by this author on:
Geological Society of London
Volume
413
ISBN electronic:
9781862397170
Publication date:
January 01, 2015

References

Related

A comprehensive resource of eBooks for researchers in the Earth Sciences

Related Articles
Related Book Content
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal