Wave Velocities below the Mohorovičić Discontinuity
- Creators
- Gutenberg, B.
Abstract
The velocities of longitudinal waves immediately below the Mohorovičić discontinuity which have been found by various authors for continental regions decrease on the average from about 8.2 km/s, if the Mohorovičić discontinuity is at a depth of 30 km, to about 8.0 km/s, if it is at a depth of 50 km. The rate of this decrease in velocity of 0.011 ± 0.0016 km/s per km is statistically significant and exceeds appreciably the critical rate of about 0.0013 km/s per km, required for a low-velocity channel. The corresponding calculated average decrease in the velocity of transverse waves from about 4.64 km/s, if the Mohorovičić discontinuity is at a depth of 30 km, to about 4.56 km/s, if it is at 50 km (at a rate of 0.004 ± 0.0056 km/s per km) can be expected to represent average conditions under continents only if this decrease in velocity is considered in connection with that for longitudinal waves. For a depth of about 60 km, both calculated velocity-depth curves connect smoothly with those found by the author from the apparent velocities at the points of inflection of travel-time curves for earthquakes originating at various depths. The new results confirm the hypothesis that under continents the asthenosphere low-velocity channel starts at the Mohorovičić discontinuity.
Additional Information
Copyright © 1959 The Royal Astronomical Society. Received August 1959. Contribution No. 939 from the Division of the Geological Sciences, California Institute of Technology.Attached Files
Published - Geophys._J._Int.-1959-Gutenberg-348-52.pdf
Files
Name | Size | Download all |
---|---|---|
md5:5061c71581e2ece86bbfee69ee4d5d24
|
324.5 kB | Preview Download |
Additional details
- Eprint ID
- 51899
- Resolver ID
- CaltechAUTHORS:20141118-102527267
- Created
-
2014-11-18Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field
- Other Numbering System Name
- Caltech Division of Geological Sciences
- Other Numbering System Identifier
- 939