Glass geochemical data of Late Quaternary tephra from Main Ethiopian Rift (NERC grant NE/L013533/1)

Glass major element geochemical data on Late Quaternary tephra deposits from the Main Ethiopian Rift volcanoes. These data were acquired using Electron Microprobe Analysis, and secondary standard data (MPI-DING glasses) are also included. All samples were given a unique name related to the outcrop from which they were obtained. Outcrops are named "MER" followed by a 3-digit number (e.g. MER153). Samples from a given outcrops are given the same name, followed by a letter (e.g. MER153A). Outcrop localities, with GPS coordinates (Lat Long WGS84) and brief description of the geology are also included. These data are published as Supplementary Files to a paper published in Journal of Volcanology and Geothermal Research: Fontijn et al (2018), https://doi.org/10.1016/j.jvolgeores.2018.02.001.

Date (Creation): 2018-02-15

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

Point of contact

University of Oxford - Karen Fontijn ( Department of Earth Sciences )

South Parks Road , Oxford , OX1 3AN ,

Maintenance and update frequency: notApplicable notApplicable

GEMET - INSPIRE themes, version 1.0

Geology

BGS Thesaurus of Geosciences

NGDC Deposited Data
Volcanic rocks
Rift zone
Rift valleys
Volcanic ejecta

dataCentre

NGDC Deposited Data

Keywords

NERC_DDC

Access constraints: otherRestrictions Other restrictions

Other constraints: no limitations

Other constraints: The dataset is made freely available for access, e.g. via the Internet. Either no third party data / information is contained in the dataset or BGS has secured written permission from the owner(s) of any third party data / information contained in the dataset to make the dataset freely accessible.

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: EnglishEnglish

Topic category

Geoscientific information

Geographic identifier

Main Ethiopian Rift [id=985019]

Date (Creation): 1979

Begin date: 2015-10-08

End date: 2017-03-17

Supplemental Information: Lead grant NE/L013932/1

Unique resource identifier: WGS 84 (EPSG::4326)

Distribution format

MS Excel ()

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

Hierarchy level: dataset Dataset

Other: dataset

Conformance result

Date (Publication): 2011

Explanation: See the referenced specification

Pass: No

Conformance result

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: 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.