3-D P wave velocity model for the Puget Basin
region
Interactive Map View:
This page is an interactive map view through a 3-D
high resolution P
velocity model of the greater Puget basin region of western
Washington. The model is derived from inversion of active source
and earthquake
arrival times. Abbreviated information relevant to the velocity model
and its
construction is given below. The display requires Javascript browser
support (Javascript must be enabled in the users browser). A large
amount of data (> 20 Mb) must be loaded for the interactive display
to work, so please allow time for loading of the data.
Each (depth selectable) map view shows contours of P velocity at a
depth
shown by the gray bar at the right of the map, and shown in km below
sea level at lower right. The geographic origin
of the
x-y coordinates is -124.5 W and 46.25 N. Shown on the map are
coastlines, cities and
selected towns, lat/lon grid at 1/2 degree intervals, and significant
volcanoes and
mountains. In addition, earthquake epicenters are shown as black dots
for events used
in the inversion (highly selected) and within +/- 1 km of the
contour map depth. Near the surface, black dots show the
effective source locations used in several active source experiments,
including the SHIPS experiments. These near surface effective sources
include
both actual explosion sources, and stations switched as sources using
source-receiver reciprocity.
Hashered regions on the map
indicates areas of the model that are not directly
constrained by rays used in the inversion. Map scales (eastward and
northward) are shown in km along bottom and left sides.