CENTRAL UNITED STATES VELOCITY MODEL VERSION 1: DESCRIPTION AND VALIDATION
Leonardo Ramirez-Guzman, Robert A. Williams, Oliver Boyd and Stephen Hartzell (USGS).
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A PIECE OF THE PUZZLE
Project: Earthquake simulations in the New Madrid Seismic Zone: The 1811–1812 Bicentennial.
Continious representationDiscretized representation
(etree)
Source definitionDeterministic and
Probablistic
1Hz (FEM HERCULES) 1D LAYERED STRUCTURE
Conceptual framework similar to those already done for 1906 and 1868 Hayward (Bay Area) and Shakeout (Southern CA) scenarios.
Input
Solver
Model Extension
Topographic map showing the extension of the CUSVM and earthquakes greater than magnitude 2.5 (red circles) that occurred after 1972.
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Model Overview. The white lines delineate the boundaries between the oldest units. The colormap indicates the Vs (m/s) distribution.
Moho
Precambrian Unconformity
Upper Mantle
TN
IL
MO
IN
KY
ARAL
Lower Crust
Upper Crust (ENA Model)
VELOCITY MODEL
Modified Lower
Crust
Vs(m
/s)
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Vs(m/s)
SHALLOW STRUCTURE
0 500 1000 1500 2000
Shallow structure. Velocity and topography. The colormap indicates the Vs (m/s) distribution.
St. Louis Arch
St. Louis
Memphis
St. Louis area
Memphisarea
Latit
ude
Latit
ude
Latitude