|
|
|
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
LAMONT GEOLOGICAL OBSERVATORY (COLUMBIA UNIVERSITY), PALISADES, NEW YORK
Abstract
Mantle Rayleigh waves from the Kamchatka earthquake of November 4, 1952, are analyzed. The new Palisades long-period vertical seismograph recorded orders R6R15, the corresponding paths involving up to seven complete passages around the earth. The dispersion data for periods below 400 sec. are in excellent agreement with earlier results and can be explained in terms of the known increase of shear velocity with depth in the mantle. Data for periods 400-480 sec. indicate a tendency for the group velocity curve to level off, suggesting that these long waves are influenced by a low or vanishing shear velocity in the core. Deduction of internal friction in the mantle from wave absorption gives a value 1/Q = 370 x 105 for periods 250-350 sec. This is a little over half the value reported earlier for periods 140-215 sec.
Footnotes
* This research has been supported by the Geophysics Research Division of the Air Force Cambridge Research Center under Contract AF 19(122)441.
This article has been cited by other articles:
![]() |
A. Ben-Menahem A concise history of mainstream seismology: Origins, legacy, and perspectives Bulletin of the Seismological Society of America, August 1, 1995; 85(4): 1202 - 1225. [Abstract] [PDF] |
||||
![]() |
H. K. GUPTA, D. C. NYMAN, and M. LANDISMAN Shield-like upper mantle structure inferred from long-period Rayleigh- and Love-wave dispersion investigations in the Middle East and southeast Asia Bulletin of the Seismological Society of America, February 1, 1977; 67(1): 103 - 119. [Abstract] [PDF] |
||||
![]() |
L. REITER Reflection, refraction and mode conversion of long-period surface waves and the measurement of Q-1 for free oscillations Bulletin of the Seismological Society of America, October 1, 1973; 63(5): 1709 - 1722. [Abstract] [PDF] |
||||
![]() |
H. K. GUPTA and T. SANTO Worldwide investigation of the mantle Rayleigh-wave group velocities: I. Dispersion data for thirty-one new great-circle paths Bulletin of the Seismological Society of America, February 1, 1973; 63(1): 271 - 281. [Abstract] [PDF] |
||||
![]() |
K. HAMADA Mantle-wave analysis by a phase-equalization-and-sum method for the Montana LASA long-period data Bulletin of the Seismological Society of America, August 1, 1971; 61(4): 875 - 892. [Abstract] [PDF] |
||||
![]() |
J. N. BRUNE Attenuation of dispersed wave trains Bulletin of the Seismological Society of America, January 1, 1962; 52(1): 109 - 112. [Abstract] [PDF] |
||||
![]() |
J. DORMAN, M. EWING, and J. OLIVER Study of shear-velocity distribution in the upper mantle by mantle Rayleigh waves Bulletin of the Seismological Society of America, January 1, 1960; 50(1): 87 - 115. [Abstract] [PDF] |
||||
![]() |
J. OLIVER and M. EWING Microseisms in the 11- to 18-second period range Bulletin of the Seismological Society of America, April 1, 1957; 47(2): 111 - 127. [Abstract] [PDF] |
||||
![]() |
F. PRESS, M. EWING, and J. OLIVER Crustal structure and surface-wave dispersion in Africa Bulletin of the Seismological Society of America, April 1, 1956; 46(2): 97 - 103. [PDF] |
||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |