Date ( Creation )

2018-02-15

Identifier

http://data.bgs.ac.uk/id/dataHolding/13607279

Maintenance and update frequency

notApplicable notApplicable

GEMET - INSPIRE themes

• Geology

BGS Thesaurus of Geosciences

• Volcanic ejecta , Volcanic rocks , Rift valleys , Rift zone

Keywords

• NERC_DDC

Access constraints

otherRestrictions Other restrictions

Use constraints

otherRestrictions 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

Available under the Open Government Licence subject to the following acknowledgement accompanying the reproduced NERC materials "Contains NERC materials ©NERC [year]"

Metadata language

English English

Topic category

• Geoscientific information

Geographic identifier

Main Ethiopian Rift [id=985019]

 

Date ( Creation )

1979

N

S

E

W

Supplemental Information

Lead grant NE/L013932/1

Distribution format

• MS Excel ()

OnLine resource

http://www.bgs.ac.uk/services/ngdc/accessions/index.html#item107289  

Hierarchy level

dataset Dataset

Other

dataset

Statement

Tephra samples were manually crushed, wet-sieved at 80 µm to remove alteration products, and dried at 50 °C. Ash shards were mounted in EpoFix resin and polished. Glass major element analyses was carried out by Electron Microprobe Analysis using a 4-spectrometer JEOL JXA-8600 Superprobe, with an accelerating voltage of 15 kV, a defocused beam of 10 (or 5) µm, and 6 (or 4) nA beam current. Elements were counted on-peak for 30 s (Si, Al, Fe, Ti, Mg, Ca, K), except for Na (12 s, analysed first), P (60 s), Mn and Cl (50 s). Off-peak background counting times were half the peak counting times. Data quality was continuously monitored by secondary glass standard analyses. Thirty individual points were attempted per sample. Only analyses with totals above 90 wt% were retained.

gmd:MD_Metadata

File identifier

677076df-dcc3-7230-e054-002128a47908   XML

Metadata language

English English

Hierarchy level

dataset Dataset

Date stamp

2021-06-14

Metadata standard version

2.3

Dataset URI

http://data.bgs.ac.uk/id/dataHolding/13607279