On the layer of relatively low wave velocity at a depth of about 80 kilometers
- Creators
- Gutenberg, B.
Abstract
More than twenty years ago, the author (Gutenberg, 1926) pointed out that the longitudinal waves of shallow earthquakes decrease considerably in amplitude at epicentral distances between a few (say 2) degrees and about 15 degrees. At greater distances the amplitudes become again rather large, at 16° epicentral distance about as large as at 2°. With further increase in epicentral distance the amplitudes decrease slowly, The whole phenomenon was interpreted as due to a decrease in wave velocity at a depth between 70 and 80 km. Further investigations (Gutenberg and Richter, 1931; 1935, pp. 335-343; 1939a; Gutenberg, 1945a; 1945c, pp. 126-127) indicate that the decrease in velocity must be rather small, that the shadow zone is less significant in earthquakes which start at a depth of 150 to 250 km. and is absent in earthquakes originating at a depth of more than about 300 km.
Additional Information
Copyright © 1948 by the Seismological Society of America. Manuscript received for publication December 11, 1947.Attached Files
Published - 121.full.pdf
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Additional details
- Eprint ID
- 47728
- Resolver ID
- CaltechAUTHORS:20140731-143020093
- Created
-
2014-07-31Created from EPrint's datestamp field
- Updated
-
2022-01-28Created from EPrint's last_modified field
- Other Numbering System Name
- Balch Graduate School of the Geological Sciences
- Other Numbering System Identifier
- 420