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Quantitative Seismology: Theory and Methods
We study fracture and rupture propagation as models of an earthquake, and we supplement these theoretical subjects with practical descriptions of how seismographs work and how data are analyzed and inverted. Expand
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EUVAC: A solar EUV Flux Model for aeronomic calculations
This paper presents a new solar EUV flux model for aeronomic calculations (EUVAC), which is based on the measured F74113 solar EUV reference spectrum. The model provides fluxes in the 37 wavelengthExpand
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Seismological evidence for differential rotation of the Earth's inner core
The travel times of seismic waves that traverse the Earth's inner core show a systematic variation over the past three decades. Expand
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Bulletin of the Seismological Society of America
The rupture process occurring during an earthquake is described here in terms of one of the few known solutions to a problem of brittle fracture, in which rupture originates at a point, and spreadsExpand
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An improved algorithm for determining neutral winds from the height of the F2 peak electron density
One of the greatest uncertainties in modeling the ionospheric densities and temperatures lies in the neutral winds that affect the vertical ion drift. Wind measurements are difficult to make, andExpand
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Equatorial plasma fountain and its effects over three locations: Evidence for an additional layer, the F 3 layer
The equatorial plasma fountain and equatorial anomaly in the ionospheres over Jicamarca (77°W), Trivandrum (77°E), and Fortaleza (38°W) are presented using the Sheffield UniversityExpand
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Thermal He+ in the plasmasphere: Comparison of observations with numerical calculations
Observations from the retarding ion mass spectrometer (RIMS) on the Dynamics Explorer 1 (DE-1) satellite arc used to examine He{sup +} and its relation to H{sup +}. These observed values are alsoExpand
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Ratios of photoelectron to EUV ionization rates for aeronomic studies
This study reveals that the ratios of the photoelectron to EUV ionization rates are not constant but depend on the degree of attenuation of the solar EUV flux and on the transport of photoelectrons.Expand
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Use of FUV auroral emissions as diagnostic indicators
In an earlier study we modeled selected FUV auroral emissions (O I (1356 A), N2 Lyman-Birge-Hopfield (LBH) (1464 A), and LBH (1838 A)) to examine the sensitivity of these emissions and their ratiosExpand
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We have studied scattered pulse shapes by modeling inhomogeneities as a sequence of infinitesimally thin homogeneous layers. With oblique incidence of plane P or SV waves, theExpand
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