UCL Discovery Stage
UCL home » Library Services » Electronic resources » UCL Discovery Stage

How phyllosilicate mineral structure affects fault strength in Mg-rich fault systems

Sanchez-Roa, C; Faulkner, DR; Boulton, C; Jimenez-Millan, J; Nieto, F; (2017) How phyllosilicate mineral structure affects fault strength in Mg-rich fault systems. Geophysical Research Letters , 44 (11) pp. 5457-5467. 10.1002/2017GL073055. Green open access

[thumbnail of S-nchez-Roa_et_al-2017-Geophysical_Research_Letters.pdf]
Preview
Text
S-nchez-Roa_et_al-2017-Geophysical_Research_Letters.pdf - Published Version

Download (3MB) | Preview

Abstract

The clay mineralogy of fault gouges has important implications for the frictional properties of faults, often identified as a major factor contributing to profound fault weakness. This work compares the frictional strength of a group of Mg‐rich minerals common in the Mg‐Al‐Si‐O compositional space (talc, saponite, sepiolite, and palygorskite) by conducting triaxial frictional tests with water or argon as pore fluid. The studied minerals are chemically similar but differ in their crystallographic structure. Results show that fibrous Mg‐rich phyllosilicates are stronger than their planar equivalents. Frictional strength in this group of minerals is highly influenced by strength of the atomic bonds, continuity of water layers within the crystals, and interactions of mineral surfaces with water molecules, all of which are dictated by crystal structure. The formation and stability of the minerals studied are mainly controlled by small changes in pore fluid chemistry, which can lead to significant differences in fault strength.

Type: Article
Title: How phyllosilicate mineral structure affects fault strength in Mg-rich fault systems
Open access status: An open access version is available from UCL Discovery
DOI: 10.1002/2017GL073055
Publisher version: https://doi.org/10.1002/2017GL073055
Language: English
Additional information: This is the published version of record. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: frictional strength, fault gouge, phyllosilicates, clay minerals
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences
URI: https://discovery-pp.ucl.ac.uk/id/eprint/10050838
Downloads since deposit
2,546Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item