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Date Permissions Signed


Date of Award

Summer 2022

Document Type

Masters Thesis

Department or Program Affiliation


Degree Name

Master of Science (MS)



First Advisor

Caplan-Auerbach, Jacqueline

Second Advisor

Roland, Emily Carlson

Third Advisor

Chadwick, William W.

Fourth Advisor

Dziak, Robert P.


West Mata Volcano located in the NE Lau Basin is the site of the deepest observed submarine volcanic eruption, 1,200 meters below sea level. In May 2009, a research cruise collected video data of two eruptive vents showcasing different eruption styles. During the same research cruise, a BprobeTM portable hydrophone was deployed at the summit of West Mata and collected data that coincides with video recorded at the vents during ROV dives. These data sets were correlated to better understand the spectral signatures associated with the two eruptive vents. Both vents were near the summit, about 50 meters apart, and exhibit different eruptive styles. Hades vent exhibited bubble bursting described as Strombolian-style, while Prometheus vent exhibited active degassing, and slight lava fountaining referred to as Hawaiian-style. In December 2009, a moored hydrophone array consisting of four stations to the north, east, south, and west of West Mata collected data for up to two years. Short-term changes in eruptive behavior provide evidence of transitioning flow regimes. As Hades exhibited periods of singular bursting, while other times there were successive bursting events, it exhibited transitions from bubbly (successive bursts) to slug (singular bursts) flow. This switch in flow regime may have been caused by a slower magma rise rate that allowed bubble coalescence. Prometheus vent generated Hawaiian-style eruptions which also produced bubbly to slug flow regimes. Due to an eruptive vent filled with volcanic debris, bubbles were broken up as they moved through the rubble, thus producing the active degassing. Based on these observations, a time sequence of events is presented here to characterize the eruptive sequences at the West Mata vents, supported by the observed long-term trends in the hydrophone data and changes in bathymetry. These data are used to infer an evolution of the magmatic plumbing system during the 2009-2011 eruptive activity at West Mata.




Submarine volcanism, hydroacoustics, West Mata, NE Lau Basin


Western Washington University

OCLC Number


Subject – LCSH

Submarine volcanoes--Polynesia; Volcanic eruptions--Polynesia; Underwater acoustics--Polynesia

Geographic Coverage





masters theses




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Rights Statement

colorbar_axis.m (8 kB)
Color bar script for spectrograms

date2jul.m (1 kB)
Date script for spectrograms

hydrophone_corr.m (3 kB)
hydrophone script 1

hydrophone_mata.m (3 kB)
hydrophone data West Mata

hydrophone_sdat.m (1 kB)
South hydrophone data

jfft.m (3 kB)
spectrogram filter 1

jfiltfilt.m (1 kB)
spectrogram filter 2

jspecgram.m (2 kB)
spectrogram script 1

jspecgram2.m (3 kB)
spectrogram script 2

jul2day.m (1 kB)
hydrophone data script 2

mata_all_stations.m (1 kB)
west mata data

mata_video.m (1 kB)
west mata video data

mmread.m (25 kB)
video read script

processFrame.m (3 kB)
video script (1 kB)
spectrogram color scheme

0506First70sec.mp4 (6254 kB)
Eruption video 1

0506Video.mp4 (1422 kB)
Eruption video

0506Video2.mp4 (6094 kB)
Eruption video 2

0506Video3.mp4 (4998 kB)
Eruption video 3

0506Video4.mp4 (2982 kB)
Eruption Video 4

0507Video1.mp4 (6622 kB)
Eruption Day 2 Video 1

0507Video2.mp4 (7965 kB)
Eruption Day 2 Video 2

0507Video3.mp4 (7499 kB)
Eruption Day 2 Video 3

0507Video4.mp4 (4513 kB)
Eruption Day 2 Video 4

mata2.mp4 (1936 kB)

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