New Madrid GPS

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New Madrid GPS Status and Future Apr 2007 Bob
Smalley John Puchakayala James Davis
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Residual horizontal site velocities (Newman et
al., 1999)..
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Is deformation occurring? (better/definitive
answer needs more cGPS stations and longer
measurements)
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Residual velocities w.r.t. stable North
America (defined using sites east of 100W and
south of 40N - wrms 0.4 mm)
Calais and DeMets, unpublished solution, Nov. 2006
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Detecting small signal buried in larger signal No
noise
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Detecting small signal buried in larger
signal With noise
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New Madrid GPS Velocity Field
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Monument comparison
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Can high precision GPS be used to test different
models?
Elastic strain accumulation
Visco-elastic relaxation 1811-12
Parameters from Rydelek Pollitz, 1994 Pollitz,
1997 code
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High Rate GPS (1 sec or faster)
Large amplitude (strong or weak motion)
displacement seismometer
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Conclusions Controversial observation strain
associated with one of New Madrid fault zone
structures For crustal deformation - need
more Time Stations
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The End