Geometry and Kinematics of continental breakup in the youthful Aden rift

One of the primary processes shaping Earth's surface is the stretching and eventual break-up of continents to create new ocean basins. The processes of stretching and heating of -150 km-thick plates, or layers of rock, are made evident at Earth's surface via earthquakes, volcanoes, hot springs, landslides and rockfalls that occur within and along the margins of narrow, long basins flanked by steep mountain ranges (e.g., East African rift, Gulf of Corinth). Ancient areas of stretching are more difficult to decipher, since the physical processes we wish to understand have since stopped, and competing processes of erosion, sedimentation, and subsidence of the rift zones makes them difficult to image. Finally, studies of continental break-up require an understanding of margins on both sides of ocean basins, which may now be 1000's of km apart (e.g., N. Atlantic). We propose to determine the evolution of continental rifting leading to break-up in the Gulf of Aden, where break-up occurred <20 My ago, and both margins are within a day's shiptime from one another. The short time interval since break-up means that sedimentary strata overlying the stretched, fractured, and heated rock layers of the plate are thin, and we can image clearly using geophysical methods. Our experiment involves the analyses of the travel times of seismic waves through the rock layers of the plates and underlying mantle where rocks are hotter, and where pockets of molten rock may have accumulated. Electronic devices capable of measuring vibrations from earthquakes worldwide (seismometers) will be buried along onshore continuations of profiles across the Gulf of Aden. We intend to use both man-made sound sources generated onboard the French seismic research vessel Marie Dufresne, which will travel along 3 profiles of the Gulf of Aden sending airblasts into the water every 50 metres. Our instruments will also record earthquakes occurring in the Himalayas, the Atlantic mid-ocean ridge, the Mediterranean sea, and the East African rift system. Variations in the arrival times of these sound waves recorded across our array allow us to map out velocity structure of the rocks beneath the array and across the width of the Gulf of Aden. Our aims are to map the geometry of the stretched layers within the plates, as well as their variations in velocity and physical properties. The velocity variations help us detect small variations in temperature and/or composition of the rocks, and help us determine the mechanical properties of the plates as they are stretched. Do the plates come apart along one large fracture, or fault zone, or does the stretching move continually inward to a narrow zone of necking, much like one finds stretching blue tack? Has some of the hot mantle rock which passively rises up to fill the place previously occupied by the plate depressurise and melt to form lavas? Where do these lavas form and rise up? Are these properties continuous along the length of the rift zone, or is the process three-dimensional? All of this information is vitally important to 1) oil explorationists trying to improve predictive models for oil and gas generation and migration 2) planners and government officials who need to evaluate seismic and volcanic hazards in areas of active rifting 3) earth scientists who wish to understand the physical properties of rocks so that we can adequately describe the physics of continental break-up and predict the onset of seafloor spreading. Funds are requested to cover travel to and from Oman to deploy instruments, to download data every 6 weeks (3 months) and every 12 weeks (9 months), plus travel to partner institutions to confer and integrate research results.

Date (Creation): 2005-09-01

Citation identifier: http://data.bgs.ac.uk/id/dataHolding/13605323

Point of contact

Organisation name	Individual name	Electronic mail address	Role
Unviersity of Rochester	Ebinger, Professor J	not available	Principal investigator
British Geological Survey	Enquiries	enquiries@bgs.ac.uk	Distributor
British Geological Survey	Enquiries	enquiries@bgs.ac.uk	Point of contact

Maintenance and update frequency: notApplicable

GEMET - INSPIRE themes, version 1.0

Geology

BGS Thesaurus of Geosciences

Earth core
Earth surface
Tectonics
Natural resources
NGDC Deposited Data
Natural hazards
Earth mantle

dataCentre

NGDC Deposited Data

Keywords

NERC_DDC

Access constraints: Other restrictions

Other constraints: intellectualPropertyRights

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Use constraints: Other restrictions

Other constraints: The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused.

Other constraints: Either: (i) the dataset is made freely available, e.g. via the Internet, for a restricted category of use (e.g. educational use only); or (ii) the dataset has not been formally approved by BGS for access and use by external clients under licence, but its use may be permitted under alternative formal arrangements; or (iii) the dataset contains 3rd party data or information obtained by BGS under terms and conditions that must be consulted in order to determine the permitted usage of the dataset. Refer to the BGS staff member responsible for the creation of the dataset if further advice is required. He / she should be familiar with the composition of the dataset, particularly with regard to 3rd party IPR contained in it, and any resultant use restrictions. This staff member should revert to the IPR Section ( ipr@bgs.ac.uk) for advice, should the position not be clear.

Language: English

Topic category

Geoscientific information

Geographic identifier: GULF OF ADEN [id=2001406]
British Geological Survey Gazetteer: Gazetteer of sea areas 2010 revision

Geographic identifier: Gulf of Aden Rift [id=985017]
British Geological Survey Gazetteer: Geographical hierarchy from Geosaurus 1979 creation

Begin date: 2005-09-01

End date: 2007-08-31

Supplemental Information: NE/C514031/1 Geometry and Kinematics of continental breakup in the youthful Aden rift, all seismic data from this project are archived at Seis-UK.

Reference System Information

No information provided.

Distribution format

Name	Version

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
British Geological Survey	Enquiries	enquiries@bgs.ac.uk	Distributor

OnLine resource

Protocol	Linkage	Name
WWW:LINK-1.0-http--link	https://www.bgs.ac.uk/	BGS Homepage

Hierarchy level: Dataset

Other: dataset

Conformance result

Title: INSPIRE Implementing rules laying down technical arrangements for the interoperability and harmonisation of Geology

Date (Publication): 2011

Explanation: See the referenced specification

Pass: No

Conformance result

Title: Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services

Date (Publication): 2010-12-08

Explanation: See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF

Pass: No

Statement: See scientific paper in project folder, "Evidence of partial melting beneath a continental margin: case of Dhofar, in the Northeast Gulf of Aden (Sultanate of Oman)" W:\Teams\RM\NERCResearch\ESAA\Project_13605323