Results 251 to 260 of about 6,954 (297)

Downward continuation of Geopotential in Switzerland

2008
Die Doktorarbeit untersucht die Möglichkeiten, das Potentials der Erde durch Fortsetzung nach unten zu bestimmen. Als Ausgangsdaten werden Schwerewerte, die durch Fluggravimetrie über der Schweiz beobachtet wurden, benutzt. Die Bearbeitung der Ergebnisse von Fluggravimetrierungen über alpinen Gegenden stellt wegen der großen Flughöhe und der sehr rauen
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Downward continuation of moveout-corrected seismograms

Geophysics, 1972
Abstract Earlier work developed a method of migration of seismic data based on numerical solutions of partial differential equations. The method was designed for the geometry of a single source with a line of surface receivers. Here the method is extended to the geometry of stacked sections, or what is nearly the same thing, to the ...
Jon F. Claerbout, Stephen M. Doherty
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Convergence and divergence in downward continuation

Geophysics, 1967
Abstract The paper reports solutions for some unanswered questions regarding the properties of the downward continued field for some simple source configurations. The radii of convergence, the conditions for predicting presence or absence of singularities on the boundary of the region of convergence and the equations for the boundary ...
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Downward continuation of heat flow data

Tectonophysics, 1989
Abstract Downward continuation operators are derived and used to calculate the subsurface temperature from surface heat flow data. If the distribution of the shallow heat sources were known, their effect on the temperature field could be included in the downward continuation operator.
J.C. Mareschal, Y. Hamdani, D.M. Jessup
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Solution of the downward continuation problem by collocation

Bulletin géodésique, 1975
The modern satellite techniques enable to measure the gravity acceleration in space. The downward continuation of this measurements to the earth's surface is by the closed theory practically impossible. Using the method of collocation we can estimate the values of Δ g in the limited region underneath the observation with a little loss of accuracy ...
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Velocity downward continuation through generative models

19th Congress of the Brazilian Geophysical Society - Proceedings
Velocity model building (VMB) should comply with the physics involved in wave propagation and honor the location of the recording surface in which we extract the information. Thus, we propose using a generative model to predict velocity from shallow to deep.
T. Alkhalifah, R. Hasroku, S. Cheng
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Comparative Study of the Spherical Downward Continuation

Surveys in Geophysics, 2015
Downward continuation of the potential data (gravity or magnetic) helps to interpret contributing sources by transforming the physical signal to their neighborhood. This paper applies three continuation approaches (Landweber’s iteration, the direct method and the inverse-matrix approach with Tikhonov’s regularization), based on the Poisson integral ...
Josef Sebera, Martin Pitoňák, Eliška Hamáčková, Pavel Novák   +3 more
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Upward and downward continuations in the geopotential determination

Bulletin Géodésique, 1979
The geopotential on and outside the earth is represented as a series in surface harmonics. The principal terms in it correspond to the solid harmonics of the external potential expansion with the coefficients being Stokes’ constantsCnm andSnm. The additional terms which occur near the earth’s surface due to its non-sphericity and topography are ...
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Analysis on Convergence of Iteration Method for Potential Fields Downward Continuation and Research on Robust Downward Continuation Method

Chinese Journal of Geophysics, 2009
AbstractGeomagnetic navigation is a new navigation technology and has very important significance for the national defence. Spatial geomagnetic database is a precondition for implementing geomagnetic navigation. Potential field continuation is an effective method for designing geomagnetic database.
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Downward Continuation of the Gravitational Potential

1991
Clerk Maxwell’s form of the attraction potential at an external point, distant r from an internal origin, can be written in the tensor form $$- \frac{V}{G} = \sum\limits_{{n = 0}}^{\infty } {\frac{{{{{( - 1)}}^{n}}}}{{n!}}} {{I}^{{stu \ldots (n)}}}{{\left( {\frac{1}{r}} \right)}_{{stu \ldots (n)}}},$$ (1) in which the lower indices imply ...
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