Results 111 to 120 of about 6,478 (164)

Downward continuation of Helmert's gravity

Journal of Geodesy, 1996
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Vaníček, P., Sun, W., Ong, P., Martinec, Z., Najafi, M., Vajda, P., ter Horst, B.   +6 more
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The downward continuation of the tilt angle

Near Surface Geophysics, 2016
ABSTRACTThe tilt angle filter can be used both to enhance images of aeromagnetic data and as the basis of semi‐automatic interpretation methods. For vertically magnetised and vertically dipping contacts, rescaling by factor is equivalent to computing from sources with all depths decreased by a factor .
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Wavelet transforms and downward continuation

1994
Applications of wavelet theory [5, 6] to the numerical solution of partial differential equations and integral operators is a rapidly developing topic of research [1]. For a large class of integral operators, with smooth slowly decaying kernels, the matrices approximating these operators which are dense in the natural basis become sparser for the same ...
Ronan Bras, George Mellman
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Wavelet transform method for downward continuation

SEG Technical Program Expanded Abstracts 1992, 1992
Wavelet transforms allow efficient analysis of signals in one or more dimensions. The signals may be expressed at different scales of resolution. This provides schemes for compression of informations in image and speech processing. The mathematical framework of wavelet analysis is novel and well grounded in theoretical works and the computation of ...
Ronan LeBras, George Mellman, M. Peters
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Downward continuation within the quasiharmonic region

EGM 2010 International Workshop, 2010
Downward continuation is a useful transformation, mainly used to enhance the measured field. Known limitations regard its instability and are theoretical, because the continuation level should not be deeper than the source depth. Despite of this downward continuation was used in several papers to recover source parameters with different methods here ...
M. Fedi, G. Florio
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Downward continuation of Mars SHARAD data

SEG Technical Program Expanded Abstracts 2014, 2014
Shallow Subsurface Radar (SHARAD) data from the Mars Reconnaissance Orbiter are acquired approximately 300 kilometers above the Martian polar icecap. In this report we detail how to adapt seismic 3D poststack downward continuation to allow construction of the data that would have been recorded a short distance above the Martian surface, thereby saving ...
Stewart A. Levin*, Fritz Foss
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A note on downward continuation of gravity

Geophysics, 1954
Abstract Comparing calculated and exact values in an ideal example, it is shown that Peters' proposed method of downward continuation of gravity is far less suitable than a combination of Peters' procedure for upward continuation and a finite differences method for downward continuation.
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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 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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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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