S-P-wave traveltime residuals from earthquakes and lateral inhomogeneity in the upper mantle beneath Aegean and the Hellenic Trench near Crete


Taymaz T.

GEOPHYSICAL JOURNAL INTERNATIONAL, vol.127, no.2, pp.545-558, 1996 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 127 Issue: 2
  • Publication Date: 1996
  • Doi Number: 10.1111/j.1365-246x.1996.tb04740.x
  • Title of Journal : GEOPHYSICAL JOURNAL INTERNATIONAL
  • Page Numbers: pp.545-558

Abstract

The average S-P-wave traveltime residuals from 29 earthquakes in the Aegean and the Hellenic Trench near Crete imply that there are lateral variations in structure beneath these regions. Average S-P-wave residuals, measured with respect to the Jeffreys-Bullen (J-B) tables (1940), from 14 to 17 earthquakes in the Aegean are greater than +1s. The largest positive values of residuals in the Aegean imply that the average velocities in the crust and the upper mantle of these parts of the Aegean are lower than those beneath Create. The existence of volcanoes, heat flow observations, an assumption of relatively low seismic-wave velocities, and variations in S-P-wave residuals from earthquakes in the Aegean provide evidence of lateral variations in uppermost mantle structure beneath the region. Residuals reflect systematic lateral variations that do not correlate well with elevation or with simple aspects of regional geology.