Abstract
Amplitudes of long-period PKP phases from 16 large earthquakes are investigated in the distance ranges 110°–134° and 142°–170°. A parameterized amplitude distribution in the distance range 110°–134° is compared with theoretically computed amplitudes using different velocity and density modifications of model 1066B in the inner core. An attempt is made to estimate the velocity jumps of P and S waves as well as the density jump across the inner-core boundary (ICB). The results of a preliminary analysis are:
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a)
The P-velocity jump can be restricted between 0.6 and 0.7 km/sec with a preferred value of 0.64 km/sec,
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b)
The shear wave velocity at the top of the inner core lies between 2.5 and 3.0 km/sec,
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c)
The density jump at the ICB is practically not restricted by the data because the amplitudes are not so sensitive to this jump and because of its inherent trade-off with the jump in shear wave velocity.
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© 1981 D. Reidel Publishing Company
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Häge, H. (1981). P and S-Velocity Jump at the Inner-Core Boundary from PKP Amplitudes. In: Husebye, E.S., Mykkeltveit, S. (eds) Identification of Seismic Sources — Earthquake or Underground Explosion. NATO Advanced Study Institutes Series, vol 74. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-8531-5_24
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DOI: https://doi.org/10.1007/978-94-009-8531-5_24
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