The University of Southampton
University of Southampton Institutional Repository
Warning ePrints Soton is experiencing an issue with some file downloads not being available. We are working hard to fix this. Please bear with us.

A review of tectonic models for the rifted margin of Afar: implications for continental break-up and passive margin formation

A review of tectonic models for the rifted margin of Afar: implications for continental break-up and passive margin formation
A review of tectonic models for the rifted margin of Afar: implications for continental break-up and passive margin formation
The Afar region represents a unique opportunity for the study of ongoing rift development and the various phases of continental break-up. In this work we discuss the geological and geomorphological characteristics of the Western Afar Margin (WAM) and the various scenarios proposed for its evolution. A drastic decline in topography and crustal thickness from the Ethiopian Plateau into the Afar Depression, as well as a series of marginal grabens and a general presence of antithetic faulting characterize the WAM. Present-day extension is mostly accommodated at the rift axis in Afar, yet the margin is still undergoing significant deformation.

Models for the evolution of the WAM involve either isostatic loading effects due to erosion, rifting-induced block rollover, large-scale detachment fault development or crustal flexure due to lithospheric stretching or magmatic loading. This wide variation of potential mechanisms for WAM development may reflect a general structural variation along the margin and in Afar, involving different stages of rift formation and possibly indicating two distinct pathways leading to continental break-up.

In order to better understand the rifting mechanisms and to fully exploit the research potential of the region, further assessment of the WAM and its relation to Afar will be necessary. The findings of such future work, combined with data from rifts and passive margins from around the globe will be of great importance to assess the processes involved in continental breakup and to better constrain the sequence of events leading from initial rifting to break-up and oceanic spreading.
Afar, Continental break-up, Lithospheric extension, Magmatic rifting, Passive margin, Rifting, Tectonics
1464-343X
Zwaan, Frank
25329ca2-014b-4cb9-9ef3-3b8a4259c675
Corti, Giacomo
dce88b12-5b7a-43b1-8a58-5bd1bc13634c
Keir, Derek
5616f81f-bf1b-4678-a167-3160b5647c65
Sani, Federico
6c59b4c4-ecca-4ecc-ba2c-66efa5e5e3df
Zwaan, Frank
25329ca2-014b-4cb9-9ef3-3b8a4259c675
Corti, Giacomo
dce88b12-5b7a-43b1-8a58-5bd1bc13634c
Keir, Derek
5616f81f-bf1b-4678-a167-3160b5647c65
Sani, Federico
6c59b4c4-ecca-4ecc-ba2c-66efa5e5e3df

Zwaan, Frank, Corti, Giacomo, Keir, Derek and Sani, Federico (2020) A review of tectonic models for the rifted margin of Afar: implications for continental break-up and passive margin formation. Journal of African Earth Sciences, 164, [103649]. (doi:10.1016/j.jafrearsci.2019.103649).

Record type: Article

Abstract

The Afar region represents a unique opportunity for the study of ongoing rift development and the various phases of continental break-up. In this work we discuss the geological and geomorphological characteristics of the Western Afar Margin (WAM) and the various scenarios proposed for its evolution. A drastic decline in topography and crustal thickness from the Ethiopian Plateau into the Afar Depression, as well as a series of marginal grabens and a general presence of antithetic faulting characterize the WAM. Present-day extension is mostly accommodated at the rift axis in Afar, yet the margin is still undergoing significant deformation.

Models for the evolution of the WAM involve either isostatic loading effects due to erosion, rifting-induced block rollover, large-scale detachment fault development or crustal flexure due to lithospheric stretching or magmatic loading. This wide variation of potential mechanisms for WAM development may reflect a general structural variation along the margin and in Afar, involving different stages of rift formation and possibly indicating two distinct pathways leading to continental break-up.

In order to better understand the rifting mechanisms and to fully exploit the research potential of the region, further assessment of the WAM and its relation to Afar will be necessary. The findings of such future work, combined with data from rifts and passive margins from around the globe will be of great importance to assess the processes involved in continental breakup and to better constrain the sequence of events leading from initial rifting to break-up and oceanic spreading.

Text
Zwaan_2019_inpress - Accepted Manuscript
Download (6MB)

More information

Accepted/In Press date: 18 September 2019
e-pub ahead of print date: 24 October 2019
Published date: April 2020
Keywords: Afar, Continental break-up, Lithospheric extension, Magmatic rifting, Passive margin, Rifting, Tectonics

Identifiers

Local EPrints ID: 435375
URI: http://eprints.soton.ac.uk/id/eprint/435375
ISSN: 1464-343X
PURE UUID: d0ddd17a-2c21-4e21-ac45-75187ba6ea89
ORCID for Derek Keir: ORCID iD orcid.org/0000-0001-8787-8446

Catalogue record

Date deposited: 01 Nov 2019 17:30
Last modified: 26 Nov 2021 07:14

Export record

Altmetrics

Contributors

Author: Frank Zwaan
Author: Giacomo Corti
Author: Derek Keir ORCID iD
Author: Federico Sani

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×