Sharp discontinuity between the bottom of the Earth's mantle and the Earth's core, characterized by a decrease of the P-wave velocity v P von 13.7 to 8.0 km/s and of the S-wave velocity from 3.44 to 0 km/s (See Fig. 2.53 in Chapter 2 of this Manual)
Peter Bormann, Keiiti Aki, William H. K. Lee, and Johannes Schweitzer (Compilers and Amenders), Glossary of Terms Interest to Earthquake and Engineering Seismologists (Version 1), Publication records from external use of GFZ scientific infrastructure, Germany 2011. http://gfzpublic.gfz-potsdam.de/pubman/item/escido c:56137:3/component/escidoc:56143/Glossary_rev1.pd f, (ND/ Erthq - Amer) {980}