Open AccessComparison of Station Errors in Seismology
Author(s) -
Jeffreys Harold,
Singh Kehar
Publication year - 1973
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1973.tb05842.x
Subject(s) - geodesy , geology , variation (astronomy) , isostasy , azimuth , seismology , discontinuity (linguistics) , statistics , mathematics , geometry , tectonics , physics , mathematical analysis , astrophysics , lithosphere
Summary Mean residuals for P at stations are taken from works by E. P. Arnold, M. L. Gogna, and E. Herrin and J. N. Taggart; they are classified by regions of observation. For the sets with adequate numbers of observations the correlations between the authors are about +0.7, which are enough to show that some effect of stations exists but not enough to imply that considerable gain in accuracy would result from allowing for them. There are signs of a small effect of azimuth as between regions at large distances. On the hypothesis of isostasy a systematic effect of height above sea level of about 0.4 s/km was expected. The data imply that such an effect may exist in Europe and Asia; the results for America seem to depend on the standard of comparison. There is a strong correlation between mean residuals for P and S . The best fit makes the variation for S about 3 times that for P . Correlations with geology were sought but not found. Variation of the depth of the Mohorovic̆ić discontinuity was considered, but the anomalies in gravity seem to fit smaller fluctuations than the station residuals do. Variation of the thickness of sediments may contribute.