Publication Date:
1978-03-24
Description:
Both P(n), and S(n), phases recorded at distances greater than 3000 kilometers in the western Pacific have substantial amounts of energy at high frequencies, in sorne instances as high as 12 hertz for P(n) and 15 hertz for S(n), A comparison of P(n) and S(n) spectra reveals generally higher energy levels and higher proportions of high-frequency to low-frequency energy for S(n) than for P(n). Estimates of the effective quality factor, Q, indicate that the efficiency of S(n) propagation may be two or three times that of P(n). First arrivals of Pn and Sn have apparent velocities in agreement with values for the uppermost mantle, whereas maximum-energy arrivals have apparent velocities in agreement with values for the lower crust.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Walker, D A -- McCreery, C S -- Sutton, G H -- Duennebier, F K -- New York, N.Y. -- Science. 1978 Mar 24;199(4335):1333-5.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/17840787" target="_blank"〉PubMed〈/a〉
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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