Constarium
← Search

Text · collection · 2007

Internal structure of Erebus volcano, Antarctica imaged by high-resolution active-source seismic tomography and coda interferometry

Listed in NASA Earthdata CMR

Erebus volcano, Antarctica has hosted a persistent convecting phonolite lava lake for over 40 years.

Description

The lake produces small (VEI 0?1) Strombolian eruptions resulting from gas slugs rising through the upper conduit system. High-resolution (to scale lengths of several hundreds of meters) three-dimensional P-wave tomographic velocity images were obtained to a depth of approximately 600 m below the volcano surface.

Data were collected using 91 seismographs deployed over an approximately 4 by 4 km area of the summit region. Seismic illumination was provided by 12 chemical shots emplaced in shallow snow and ice boreholes. P-wave direct arrival travel-time measurements were used to invert for strong velocity anomalies (with spatial variations in Vp exceeding +/- 1 km/s) associated with the uppermost few km.

Read the rest (2 more)

Shallow anomalies correlate with fumarolic ice caves, a prominent radial chilled dike, and ring structures associated with the caldera rim. Conduit structures feeding the lava lake and other vents within the Inner Crater are evidently too small (e.g., less than many 10s of meters) to be imaged under the resolution limits of this experiment. However, combined velocity and coda interferometry scattering intensity images identify near-summit regions with both low velocity and high scattering that are candidates for magma accommodation.

Results indicate a nonaxisymmetric near-summit magmatic system that is likely constrained by heterogeneous structures in the uppermost volcano. The most extensive volume of near-summit magma likely resides approximately 500 m NW of the active Inner Crater vents at depths of 500 m and more below the surface.

Links

Topics

Inferred from text
Geophysics 70% · Image 65%
Provenance · 1 source records, 20 field assertions
SourceKeyLast seenRaw
NASA Earthdata CMRC1404253522-SCIOPS8 d agoJSON v1
FieldAssertionExtractorEvidence
access_levelsource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[field].anzsrc:group:3706enrichment · NASA CMRtaxonomy-embedding@1.1.0title+keywords+description (70%)
concepts[instrument].gcmd_instrument:not-applicablesource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[instrument].gcmd_instrument:seismometerssource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/solid-earth/tectonics/earthquakes/seismic-profilesource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/solid-earth/tectonics/earthquakes/seismic-profile/seismic-body-wavessource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/solid-earth/tectonics/earthquakes/seismic-profile/seismic-surface-wavessource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[measured_variable].gcmd:earth-science/solid-earth/tectonics/volcanic-activity/volcano-magnitude-intensitysource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[modality].local:modality:imageenrichment · NASA CMRkeyword-concept-rules@1.0.0title+description (65%)
concepts[platform].gcmd_platform:observation-basedsource · NASA CMRconnector:nasa_cmr@1.0.0
concepts[platform].gcmd_platform:volcano-observatorysource · NASA CMRconnector:nasa_cmr@1.0.0
created_datesource · NASA CMRconnector:nasa_cmr@1.0.0
descriptionsource · NASA CMRconnector:nasa_cmr@1.0.0/umm/Abstract
license_textsource · NASA CMRconnector:nasa_cmr@1.0.0
publication_datesource · NASA CMRconnector:nasa_cmr@1.0.0
spatialsource · NASA CMRconnector:nasa_cmr@1.0.0/umm/SpatialExtent
temporalsource · NASA CMRconnector:nasa_cmr@1.0.0/umm/TemporalExtents
titlesource · NASA CMRconnector:nasa_cmr@1.0.0/umm/EntryTitle
updated_datesource · NASA CMRconnector:nasa_cmr@1.0.0
version_labelsource · NASA CMRconnector:nasa_cmr@1.0.0