EE 350 Radioscience Seminar
Professor Howard Zebker
Autumn 2003-2004
Date: Wednesday, October 1, 2003
Time: 4:15 PM – Refreshments at 4:00
Location: Bldg.
TC SEQ, Room 101
4-D imaging of the Earth's subsurface
using InSAR: Moving beyond the single interferogram
Prof. Howard Zebker EE and Geophysics, Stanford University
Abstract
Interferometric synthetic aperture radar (InSAR) techniques are
perhaps the most exciting advance in geodesy in the past decade.
The ability to map surface deformation at fine resolution over
wide areas has led to many new insights into geophysical
processes. Most studies to date have resulted from analysis of a
single radar interferogram, and permit identification of
subsurface phenomena such as fault slip, magma chamber
inflation, or dynamics of the polar ice sheets. The ready
availability of multiple data sets, as afforded by ERS or other
spaceborne sensors, coupled with the decrease in computational
and data storage costs, now allows analysis of time series data
the examination of how deformation patterns change with time.
These 4-D images present much more information about how
processes at depth evolve and are more predictive about future
events, an important capability for observing natural hazards
such as earthquakes and volcanic activity. Special filters may
be devised to discriminate steadily changing deformation
patterns from those that are more episodic in nature. We review
here results from several techniques based on temporal analysis
of interferograms, including faulting on active volcanoes, pore
fluid migration due to changes in seismic stress, hydrologic
aquifer analysis, and permanent scatterer analysis of tectonic
deformation.
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