Rebecca Pearce, University College London, London, United Kingdom, Max Moorkamp, University of Leicester, Leicester, LE1, United Kingdom, Almudena Sanchez De La Muela Garzon, Birkbeck, University of London, London, WC1E, United Kingdom, Thomas M Mitchell, University College London, Department of Earth Sciences, London, United Kingdom, James Hammond, Birkbeck, University of London, London, United Kingdom, Jose M Cembrano, Pontifical Catholic University of Chile, Santiago, Chile, Jaime Araya Vargas, Pontifical Catholic University of Chile, Department of Structural and Geotechnical Engineering, Santiago, Chile and Philip G Meredith, University College London, Rock and Ice Physics and Seismological Laboratory, London, United Kingdom