Open AccessDepth Determination by use of Teleseismic P ‐arrivals
Author(s) -
Slunga R.
Publication year - 1975
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1975.tb05889.x
Subject(s) - geology , geodesy , seismology , homogeneous , travel time , crust , standard deviation , upper crust , magnitude (astronomy) , polynomial , mathematics , statistics , geophysics , physics , mathematical analysis , combinatorics , transport engineering , engineering , astronomy
Summary In order to get accurate depth estimates from teleseismic P ‐arrivals only an accurate travel‐time model must be available. A model describing the travel times to a world‐wide network from events within a specified region is presented. The following two assumptions are made. The crust and upper mantle are laterally homogeneous and the travel times from the region to each station are well approximated by a second‐order polynomial in the distance. This model is applied to events in Japan. Most events lie at depths between 30 and 80 km. We obtained time residuals with a standard deviation of 0.60 seconds which is considerably less than the commonly achieved values of 0.8–1.0 seconds for global models. The RMS depth error when locating with this model is roughly 15 km if the body wave magnitude of the event is above 5.