[iris-bulk] AGU Special Session S19: Multiple Wave Scattering

[IRIS]

Dear Colleagues,

Please consider submitting an abstract to the
following special session being organized at
this year's AGU Fall Meeting.

S19: Multiple Wave Scattering Across Length Scales in the Earth

As geophysicists strive to extract more detailed
information from the subsurface, waves with shorter
and shorter wavelengths need to be understood and
interpreted. For Earth heterogeneity on the order
of the size of the wavelength, multiple wave scattering
must be accounted for to explain the late-arriving
seismic coda.

Multiply-scattered waves require new tools for their
analysis as well as a different outlook for what
questions they can ultimately answer. For instance,
information derived from multiply-scattered waves is
inherently statistical, giving an idea of the distribution
of the Earth's microstructure.

How can we properly synthesize this statistical information
with the deterministic information provided by traditional
approaches (e.g., tomography) to address relevant questions
in earth science?

In the field of seismology, initial progress on the subject
of multiple wave scattering was driven in large part by the
late Keiiti Aki. The work of Aki and his collaborators
introduced the seismological community to the concepts of wave
diffusion and radiative transfer, among many other concepts,
such as coda Q. These ideas have evolved from the early work
and have proven effective for analyzing scattered seismic
energy in the mantle, for instance.

Furthermore, recent studies, including some of Aki's final
work in volcano seismology, suggest that the wave diffusion
picture may not always be correct. Thus, questions surrounding
the basic understanding of the physics of coda waves persist.

Other applications of multiply-scattered waves depend on the
fact that they sample the subsurface well, by definition. Thus,
multiply-scattered waves can be exploited to monitor changes
in the subsurface or to extract Green's functions between
receivers. Of particular interest is the use of coda waves
for Green's function retrieval, since most of the recent
examples of this technique have emphasized the use of oceanic
microseisms instead of coda waves. This is in spite of the
fact that the first demonstrations of Green's function retrieval
employed multiply-scattered waves.

This session aims to bring together geoscientists working on
wave propagation in heterogeneous media, including -- but not
limited to -- volcano and global seismology, high-resolution
near surface seismics, ground penetrating radar, and time-domain
electromagnetics.

The special session is also described at this URL:

http://www.agu.org/meetings/fm07/?content=search&show=detail&sessid=515

Conveners:

Kasper van Wijk
Boise State University
208-426-4604
kasper at cgiss.boisestate.edu

Matthew M. Haney
USGS Alaska Volcano Observatory
907-786-7460
mhaney at usgs.gov

Abstract submissions are due by September 6 and can be made
at this URL:

http://submissions3.agu.org/submission/entrance.asp

We look forward to an exciting session in San Francisco,

Matthew Haney
Kasper van Wijk