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Science 19 July 1968:
Vol. 161. no. 3838, pp. 263 - 264
DOI: 10.1126/science.161.3838.263
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Articles

Seismic Waves within Earth's Outer Core: Multiple Reflection

Eric R. Engdahl 1

1 Environmental Science Services Administration, Coast and Geodetic Survey, Rockville, Maryland 20852

Seismic waves reflected as many as four times within Earth's outer core are routinely recorded from large earthquakes. Observations of these waves are confined to rays near grazing incidence on the core-mantle boundary, in agreement with theoretical expectation. Minor adjustments to outer-core velocities may be necessary to account for certain of these arrivals that are not predicted by present core models. A change of 10 kilometers or more in the currently accepted core radius, 3473 kilometers, is not corroborated by the new data.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Frequency dependence of QScS.
S. A. SIPKIN and T. H. JORDAN (1979)
Bulletin of the Seismological Society of America 69, 1055-1079
   Abstract »    PDF »
Multiple inner core reflections from a Novaya Zemlya explosion.
R. D. ADAMS (1972)
Bulletin of the Seismological Society of America 62, 1063-1071
   Abstract »    PDF »
Array studies of seismic waves arriving between P and PP in the distance range 90{degrees} to 115{degrees}.
C. WRIGHT (1972)
Bulletin of the Seismological Society of America 62, 385-400
   Abstract »    PDF »
WWNSS: Seismology's Global Network of Observing Stations.
J. Oliver, J. Oliver, and L. Murphy (1971)
Science 174, 254-261
   PDF »
A velocity structure of the Earth's core.
G. G. R. BUCHBINDER (1971)
Bulletin of the Seismological Society of America 61, 429-456
   Abstract »    PDF »
Remarks on the paper "Early reflections of P'P' as an indication of upper mantle structure," by R. D. Adams.
E. R. ENGDAHL and E. A. FLINN (1969)
Bulletin of the Seismological Society of America 59, 1415-1417
   PDF »


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