ISSN:
1420-9136
Keywords:
Long-period body waves
;
Angle of incidence
;
Crustalp-wave velocities
;
NORSAR
;
seismology
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract Using simulated data, it is demonstrated that one may estimate the body wave velocity in the crust by measuring the angle of incidence ofP-waves provided only the very first part of the signal is used. This angle has been measured for a set ofP-waves at the NORSAR long period instrument sites. Combining these observations with measurements of apparent velocities, we find that the data indicates a crust velocity of 6.1±0.4 km/sec. While it is somewhat uncertain to what depth the value is representative, the observations are in obvious disagreement with previous authors who concluded that long periodP-waves were not affected by the earth's crust. Because of difficulties in separating the effects of real velocity variations from measurement errors, the details of the observedP-wave variation across the array are difficult to interpret. The consistent behavior of the data does, however, indicate that variations of approximately 3% must exist in the crustalP-wave velocity across the array.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00876134
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