Reconciling PP and P′P′ precursor observations of a complex 660 km seismic discontinuity
نویسندگان
چکیده
منابع مشابه
The nature of the 660-kilometer discontinuity in Earth's mantle from global seismic observations of PP precursors.
The 660-kilometer discontinuity, which separates Earth's upper and lower mantle, has been detected routinely on a global scale in underside reflections of precursors to SS shear waves. Here, we report observations of this discontinuity in many different regions, using precursors to compressional PP waves. The apparent absence of such precursors in previous studies had posed major problems for m...
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ژورنال
عنوان ژورنال: Geophysical Journal International
سال: 2013
ISSN: 1365-246X,0956-540X
DOI: 10.1093/gji/ggt122