Open AccessEvidence for a seismic discontinuity near 200km depth under a continental margin
Author(s) -
Drummond B. J.,
Muirhead K. J.,
Hales A. L.
Publication year - 1982
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.1982.tb06392.x
Subject(s) - geology , discontinuity (linguistics) , classification of discontinuities , lithosphere , continental margin , seismology , tectonics , mathematical analysis , mathematics
Summary. We present evidence for a seismic discontinuity near 200km depth (the Lehmann Discontinuity) under the passive continental margin of northwest Australia, where continental lithosphere merges into oceanic lithosphere. The velocity contrast across the discontinuity is 0.2–0.3 km s ‐1 , and is similar to the contrast across discontinuities at similar depths in seismic models for purely continental paths to the east under central Australia. The discontinuity has been shown to be present under continents, oceans and now at continental margins, and is probably a worldwide feature.