Skip to Main Content
Book Chapter

Tectonic and magmatic segmentation of the Global Ocean Ridge System: a synthesis of observations

By
Suzanne M. Carbotte
Suzanne M. Carbotte
1
Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA
Search for other works by this author on:
Deborah K. Smith
Deborah K. Smith
2
Woods Hole Oceanographic Institution, Woods Hole Massachusetts 02543, USA
Search for other works by this author on:
Mathilde Cannat
Mathilde Cannat
3
Equipe de Géosciences Marines, CNRS-UMR 7154, Institut de Physique du Globe, 1 rue Jussieu, 75238 Paris cedex 05, France
Search for other works by this author on:
Emily M. Klein
Emily M. Klein
4
Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
Search for other works by this author on:
Published:
January 01, 2016

Abstract

Mid-ocean ridges display tectonic segmentation defined by discontinuities of the axial zone, and geophysical and geochemical observations suggest segmentation of the underlying magmatic plumbing system. Here, observations of tectonic and magmatic segmentation at ridges spreading from fast to ultraslow rates are reviewed in light of influential concepts of ridge segmentation, including the notion of hierarchical segmentation, spreading cells and centralized v. multiple supply of mantle melts. The observations support the concept of quasi-regularly spaced principal magmatic segments, which are 30–50 km long on average at fast- to slow-spreading ridges and fed by melt accumulations in the shallow asthenosphere. Changes in ridge properties approaching or crossing transform faults are often comparable with those observed at smaller offsets, and even very small discontinuities can be major boundaries in ridge properties. Thus, hierarchical segmentation models that suggest large-scale transform fault-bounded segmentation arises from deeper level processes in the asthenosphere than the finer-scale segmentation are not generally supported. The boundaries between some but not all principal magmatic segments defined by ridge axis geophysical properties coincide with geochemical boundaries reflecting changes in source composition or melting processes. Where geochemical boundaries occur, they can coincide with discontinuities of a wide range of scales.

You do not currently have access to this article.

Figures & Tables

Contents

Geological Society, London, Special Publications

Magmatic Rifting and Active Volcanism

T. J. Wright
T. J. Wright
University of Leeds, UK
Search for other works by this author on:
A. Ayele
A. Ayele
Addis Ababa University, Ethiopia
Search for other works by this author on:
D. J. Ferguson
D. J. Ferguson
University of Leeds, UK
Search for other works by this author on:
T. Kidane
T. Kidane
Addis Ababa University, Ethiopia
Search for other works by this author on:
C. Vye-Brown
C. Vye-Brown
British Geological Survey, UK
Search for other works by this author on:
Geological Society of London
Volume
420
ISBN electronic:
9781862391345
Publication date:
January 01, 2016

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