The density and shear velocity contrast at the inner core boundary
نویسندگان
چکیده
منابع مشابه
Constraints on density and shear velocity contrasts at the inner core boundary
S U M M A R Y The density jump ( ρ ICB) at the inner core boundary (ICB) is an important constraint on the dynamics and history of the Earth’s core. Two types of seismological data sensitive to ρ ICB have been studied since the 1970s: free oscillation eigenfrequencies and the amplitudes of core reflected phases (PKiKP/PcP). The preliminary reference earth model (PREM) of Dziewonski & Anderson, ...
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15 صفحه اولShort wavelength topography on the inner-core boundary.
Constraining the topography of the inner-core boundary is important for studies of core-mantle coupling and the generation of the geodynamo. We present evidence for significant temporal variability in the amplitude of the inner core reflected phase PKiKP for an exceptionally high-quality earthquake doublet, observed postcritically at the short-period Yellowknife seismic array (YK), which occurr...
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ژورنال
عنوان ژورنال: Geophysical Journal International
سال: 1990
ISSN: 0956-540X,1365-246X
DOI: 10.1111/j.1365-246x.1990.tb04481.x