Zobrazeno 1 - 10
of 99
pro vyhledávání: '"C. J. Thomson"'
Autor:
Doug Angus, C. J. Thomson
Publikováno v:
GEOPHYSICS. 71:T137-T146
In this paper, we review the finite-difference implementation of a narrow-angle, one-way vector wave equation for elastic, 3D media. Extrapolation is performed in the frequency domain, where the second-order-accurate lateral spatial-difference operat
Autor:
C. J. Thomson
Publikováno v:
Geophysical Journal International. 163:308-323
SUMMARY Several observations are made concerning the numerical implementation of wide-angle one-way wave equations, using for illustration scalar waves obeying the Helmholtz equation in two space dimensions. This simple case permits clear identificat
Publikováno v:
Physics of the Earth and Planetary Interiors. 134:53-69
Knowledge of the velocity structure of the upper mantle beneath the Western Superior Province (WSP) is key to understanding better the accretionary processes active during the Archean. To that end, teleseismic P- and S-wave travel times recorded as p
Autor:
C. J. Thomson
Publikováno v:
Geophysical Journal International. 137:364-380
Summary A derivation is given for the factorization of the generally anisotropic, elastic wave equation into two operators which are first order with respect to a preferred direction of propagation. One factor gives the ‘one-way’ equation for for
Publikováno v:
Geological Society, London, Special Publications. 199:27-44
Publikováno v:
Grass and Forage Science. 56:97-104
Germination of annual pasture species was studied under controlled-environment conditions in south-western Australia at temperatures in the range from 4 degrees C to 35 degrees C. Subterranean clover (Trifolium subterraneum) and Wimmera ryegrass (Lol
Autor:
C. J. Thomson
Publikováno v:
Geophysical Journal International. 144:320-342
SUMMARY The coherent-state transform (CST) is essentially a Gaussian-windowed Fourier transform and it yields a combined slowness–position (p, x) domain representation of seismic wavefields. Several forms of the inverse CST exist and the set of ‘
Autor:
Brian Roberts, S. Sol, I. Asudeh, Don White, D. Francis, I. Kay, C. J. Thomson, J-Michael Kendall
Publikováno v:
University of Bristol-PURE
Shear wave splitting observations in the Archean Superior Province of the Canadian Shield show moderate to large delay times (1.1–2.1 s) with azimuths suggesting upper-mantle anisotropy is subparallel to the structural grain of the craton. Two regi
Publikováno v:
Geophysical Journal International. 132:584-594
SUMMARY The Maslov asymptotic method addresses some of the problems with standard ray theory, such as caustics and shadows. However, it has been applied relatively little, perhaps because its accuracy remains untested. In this study we examine Maslov
Publikováno v:
Annals of Botany. 81:349-354
Stagnant nutrient solution containing 0‐1% agar and with an extremely low oxygen level (‘stagnant agar solution’) was used to simulate the gaseous composition and slow gas diusion of waterlogged soils. Comparisons were made between the growth o