Deciphering volcano seismic signatures from scaled laboratory models

Technical Abstract

Volcano seismicity is an important tool used to monitor volcanic hazards, as seismic signals are commonly associated with fracturing and the movement of volcanic fluids. In investigating the relation between fluids and seismic signals, we record acoustic emissions (AEs) in the laboratory that result from fracturing and fluid depressurization through the fractured rock. We vary the fluid viscosity to create field analogues of hydrothermal and magmatic fluids. While fracturing causes high-frequency volcano-tectonic (VT)–type AE signals, fluid venting results in VT and long-period AEs with variable but overall lower dominant frequencies. The viscosity of the vented fluid correlates (1) inversely with the peak dominant frequency, (2) inversely with the number of induced AEs, (3) proportionally to the onset time of AEs, and (4) inversely with the initial rate of AE generation. Tremor was observed only in the early stages of low-viscosity fluid venting and thus may be more associated with gases and hydrothermal fluids than with magma.

Publications:

The relation between viscosity and acoustic emissions as a laboratory analogue for volcano seismicity(external link)

James Clarke; Ludmila Adam; Joel Sarout; Kasper van Wijk; Ben Kennedy; Jeremie Dautriat

Geology (2019) 47 (6): 499–503.

The influence of fluid type on elastic wave velocity and attenuation in volcanic rocks(external link)

James Clarke; Ludmila Adamb; Kasper vanWijk ; Joel Sarout 

Journal of Volcanology and Geothermal Research 403 (2020) 107004

A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in Physics(external link)

Laboratory and Numerical Experiments to Infer the Effects of Fluids on Volcano Seismicity