This article is about a discontinuity in Earth's mantle. For the discontinuity in the core, see
Earth's inner core .
Velocity of seismicS -waves in the Earth near the surface in three tectonic provinces: TNA = Tectonic North America, SNA = Shield North America and ATL = North Atlantic.[ 1] TheLehmann discontinuity is an abrupt increase ofP -waveS -wave[ 2] Earth's mantle , discovered by seismologistInge Lehmann .[ 3] [ 4] [ 5] continents , but not usually beneathoceans ,[ 6] asthenosphere , aphase transition ,[ 7] shear wave anisotropy .[ 8]
^ Figure patterned afterDon L Anderson (2007).New Theory of the Earth Cambridge University Press . p. 102, Figure 8.6.ISBN 978-0-521-84959-3 ^ Deuss, Arwen; Woodhouse, John H. (2004-09-15)."The nature of the Lehmann discontinuity from its seismological Clapeyron slopes" .Earth and Planetary Science Letters .225 (3):295– 304.doi :10.1016/j.epsl.2004.06.021 .ISSN 0012-821X . ^ William Lowrie (1997).Fundamentals of geophysics ISBN 0-521-46728-4 ^ Lehmann, I. (1936): P', Publications du Bureau Central Seismologique International, Série A, Travaux Scientifique, 14, 87–115. ^ Martina Kölbl-Ebert (December 2001)."Inge Lehmann's paper: " P' " (1936)" (PDF) . ^ Lars Stixrude and Carolina Lithgow-Bertolloni (2005)."Mineralogy and elasticity of the oceanic upper mantle: Origin of the low-velocity zone" .J. Geophys. Res .110 (B3): B03204.Bibcode :2005JGRB..110.3204S .doi :10.1029/2004JB002965 hdl :2027.42/94924 The first possible explanation is that the Lehmann is not a global feature...the Lehmann is more prevalent under continents and may be absent under all or most of the oceans. ^ Kent C. Condie (1997).Plate tectonics and crustal evolution Butterworth-Heinemann . p. 123.ISBN 0-7506-3386-7 ^ MK Savage, KM Fischer CE Hall (2004)."Strain modelling, seismic anisotropy and coupling at strike-slip boundaries..." . In John Gocott (ed.).Vertical coupling and decoupling in the lithosphere; Volume 227 of special publicationsGeological Society . p. 14.ISBN 1-86239-159-9 Shun-ichirō Karato (2008).Deformation of earth materials: an introduction to the rheology of solid earth ISBN 978-0-521-84404-8
Shells Global discontinuities Regional discontinuities
