Mechanical data on Unzen rock samples

This dataset contains raw mechanical measurements of standard uniaxial tests in 1) tension; 2) compression; 3) compression with creep deformation (load hold); 4) compression with creep and mechanical oscillations. The data is used by Schaefer et al., 2023, ( https://doi.org/10.55575/tektonika2023.1.1.10). Experiments consisted of 1) standard Uniaxial Compressive strength tests; 2) Brazilian tensile strength tests; 3) Creep tests in compression and tension; 4) Creep and mechanical oscillations tests in compression and tension. For experiments in 1 in compression, a rock cylinder of 20x40 mm (diameter x height) is loaded at a constant deformation rate in a uniaxial press, for each test type until 1) failure; 3) a target stress that is then held constant for 5h before moving to a different target stress and repeating the process; and 4) to a target stress that is then held for 30 mins before inducing stress oscillations for 40 minutes. The stress is then held constant at the end of oscillations for another 30 mins. Target stresses corresponded to 50; 60 and 70% of the average compressive strength measured in test type 1. For experiments in 1), 3) and 4) in tension, a rock disc of 40x20 mm (diameter x height) is loaded at a constant deformation rate in a uniaxial press under the same stressing configurations as in compression. More details of the methods can be found in the publication Schaefer et al., 2023. Volcanic domes and edifices are inherently unstable owing to their structure and rapid emplacement/growth, further enhanced by both mechanical and thermal variations due to the movement of magma. Understanding the long-term mechanical response and fatigue of their rock constituents is thus key to understanding their stability. Experimental datasets can help quantify the amount of deformation that rocks can sustain before failure, helping us to understand possible rock failure events at larger scale at volcanoes. All data were collected at the University of Liverpool and analysed at the University of Liverpool, UK, at the USGS, USA and LMU Munich, Germany. All samples were collected at Unzen volcano, Japan. Experiments and data analysis were carried in 2021 and 2022.

Date (Creation): 2025-10-13

Citation identifier: http://data.bgs.ac.uk/id/dataHolding/13608562

Point of contact

Organisation name	Individual name	Electronic mail address	Role
LMU Munich	Jackie Kendrick	not available	Originator
British Geological Survey	Enquiries	not available	Distributor
British Geological Survey	Enquiries	not available	Point of contact

Maintenance and update frequency: notApplicable

GEMET - INSPIRE themes, version 1.0

Geology

BGS Thesaurus of Geosciences

NGDC Deposited Data
Dacite
Rock mechanics
Compression
Tension tests

dataCentre

NGDC Deposited Data

Keywords

NERC_DDC

Access constraints: Other restrictions

Other constraints: licenceOGL

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

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

Language: English

Topic category

Geoscientific information

Begin date: 2022-02-01

End date: 2022-11-30

Reference System Information

No information provided.

Distribution format

Name	Version
Text file (.txt)

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
British Geological Survey	Enquiries	not available	Distributor

OnLine resource

Protocol	Linkage	Name
	https://webapps.bgs.ac.uk/services/ngdc/accessions/index.html#item190387	Data

Hierarchy level: Non geographic dataset

Other: non geographic 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: Standard uniaxial compression apparatus in compression, tension, with creep and/or mechanical oscillations. The data is automatically collated by the software “WaveMatrix” from the company “Instron”. The following are provided for each experiment: time (in seconds), stress (in megapascal, MPa), and axial strain (for compression, unitless) or equivalent axial strain (for tension, unitless). File names indicate the specimen’s name (e.g., UNZ1_6) and the testing conditions. File names beginning with "load_hold" indicates testing was conducted in load hold conditions, and "oscillation" indicates testing was conducted in stress-oscillation conditions. File names ending in "_tension" indicates the given test was a Brazilian disk tension experiment, and "_compression" indicates the test was conducted in uniaxial compression. For example, the filed "load_hold_UNZ1_6_tension.csv" indicates data is from a load hold test in tension (Brazilian disk test) that was conducted on block UNZ1, specimen 6.