The first second of volcanic eruptions from the Erebus volcano lava lake, Antarctica—Energies, pressures, seismology, and infrasound
Article first published online: 15 JUL 2013
©2013. American Geophysical Union. All Rights Reserved.
Journal of Geophysical Research: Solid Earth
Volume 118, Issue 7, pages 3318–3340, July 2013
How to Cite
The first second of volcanic eruptions from the Erebus volcano lava lake, Antarctica—Energies, pressures, seismology, and infrasound, (2013), J. Geophys. Res. Solid Earth, 118, 3318-3340, doi:10.1002/jgrb.50234., , , , and ,
- Issue published online: 14 AUG 2013
- Article first published online: 15 JUL 2013
- Accepted manuscript online: 11 JUN 2013 03:53AM EST
- Manuscript Accepted: 30 MAY 2013
- Manuscript Received: 27 MAY 2013
- NSF. Grant Numbers: OPP-0116577, OPP-0229305, ANT-0538414, ANT-0838817, ANT-1142083
- German Science Foundation through project. Grant Number: Ho1411-161-3. J.J.
- NSF CAREER. Grant Number: 1151662
- National Science Foundation under Cooperative Agreement. Grant Number: EAR-0552316
- Doppler radar;
- bubble burst;
- explosive eruption;
- Mt. Erebus;
 We describe a multiparameter experiment at Erebus volcano, Antarctica, employing Doppler radar, video, acoustic, and seismic observations to estimate the detailed energy budget of large (up to 40 m-diameter) bubble bursts from a persistent phonolite lava lake. These explosions are readily studied from the crater rim at ranges of less than 500 m and present an ideal opportunity to constrain the dynamics and mechanism of magmatic bubble bursts that can drive Strombolian and Hawaiian eruptions. We estimate the energy budget of the first second of a typical Erebus explosion as a function of time and energy type. We constrain gas pressures and forces using an analytic model for the expansion of a gas bubble above a conduit that incorporates conduit geometry and magma and gas parameters. The model, consistent with video and radar observations, invokes a spherical bulging surface with a base diameter equal to that of the lava lake. The model has no ad hoc free parameters, and geometrical calculations predict zenith height, velocity, and acceleration during shell expansion. During explosions, the energy contained in hot overpressured gas bubbles is freed and partitioned into other energy types, where by far the greatest nonthermal energy component is the kinetic and gravitational potential energy of the accelerated magma shell (>109 J). Seismic source energy created by explosions is estimated from radar measurements and is consistent with source energy determined from seismic observations. For the generation of the infrasonic signal, a dual mechanism incorporating a terminally disrupted slug is proposed, which clarifies previous models and provides good fits to observed infrasonic pressures. A new and straightforward method is presented for determining gas volumes from slug explosions at volcanoes from remote infrasound recordings.