Dynamic imaging of glacier structures at high-resolution using source
localization: a dense seismic array experiment.
Abstract
Dense seismic array monitoring on glaciers combined with advanced array
processing may help retrieve and locate a variety of seismic sources
with unprecedented resolution and spatial coverage. Here we present an
array methodology that goes beyond classical localization algorithms
through gathering various types of sources (impulsive or continuous)
into a single scheme and sort those by their associated array phase
coherence. We demonstrate that we can retrieve the spatial and temporal
dynamics of active crevasses with a metric resolution using sources with
high phase coherence; the presence of diffracting materials trapped in
transverse crevasses using sources with moderate phase coherence; and
the time evolution of two-dimensional maps of the subglacial water flow
drainage system using sources with low phase coherence. With the ongoing
increased use of dense seismic arrays, our study highlights the strength
of using an appropriate seismological and statistical approach to image
a wide range of subsurface structures.