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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Interpretation of the horizontal loop : EM survey with multiple separation.

Kim, Kwang-Kook January 1973 (has links)
No description available.
22

Combined travel-time and amplitude interpretation of two seismic refraction studies in Europe

Deichmann, Nicholas, January 1984 (has links)
Thesis (Ph. D.)--Swiss Federal Institute of Technology Zürich, 1984. / Vitae. Abstract also in German. Includes bibliographical references (p. 103-112).
23

Interpretation of the horizontal loop : EM survey with multiple separation.

Kim, Kwang-Kook January 1973 (has links)
No description available.
24

INDUCED POLARIZATION AND ITS INTERACTION WITH ELECTROMAGNETIC COUPLING IN LOW FREQUENCY GEOPHYSICAL EXPLORATION.

GRUSZKA, THOMAS PETER. January 1987 (has links)
Starting from the dynamic equations of electromagnetics we derive mutual impedance formulas that include the effects of induced polarization (IP) and electromagnetic (EM) coupling. The mutual impedance formulas are given for four geometries: a fullspace, a cylinder in a fullspace, a halfspace, and a layer over a halfspace. IP effects are characterized by a Cole-Cole model, the properties of which are fully investigated. From the general mutual impedance formulas specific limiting forms are defined to characterize the IP and EM effects. Using these limiting forms a framework is developed to justify the addition or multiplication of the two effects. The additive and multiplicative models are compared in the cylinder and layer geometries with the conclusion that the additive model proves to be more accurate over a wider range of frequencies than the multiplicative model. The nature of the IP and EM effects is illustrated in all four geometries showing the effects of relevant parameters. In all cases it is shown that the real part of the mutual impedance contains important IP information that is less influenced by EM effects. Finally the effects of boundaries are illustrated by the cylinder and layer geometries and a theory is developed to incorporate EM effects and IP effects from multiple regions which utilizes frequency dependent real dilution factors. We also include a brief review of some EM "removal" schemes and dilution theory approximations.
25

Lateral effects in controlled source audiomagnetotellurics.

MacInnes, Scott Charles. January 1988 (has links)
A popular electrical exploration method is controlled source audiomagnetotellurics (CSAMT). Although the CSAMT method has had practical sucess, the theory used in CSAMT interpretation remains limited. The controlled source in CSAMT is a grounded electric dipole placed as far as is practical from the survey area. When the source-receiver separation is large enough, source fields can be adequately modeled by a single plane wave and conventional magnetotelluric interpretation methods can be used. Quite often however, data collected at lower frequencies can not be interpreted with magnetotelluric algorithms. If the electrical distance between source and receiver is too small, mathematical models must explicitly include the dipolar nature of the source fields to accurately model the data. Models which include a dipole source are limited. Most interpretation of CSAMT data is based upon horizontally layered models. In this dissertation, the model of plane layers excited by an arbitrary source is extended to include the effects of lateral changes in layer thickness. The method developed for modeling undulating interfaces mimics nature more accurately than plane-layered models, while preserving the utility of quick evaluation and insight lost to more general numerical methods. While the main emphasis here is on CSAMT applications, the theoretical results are valid for any source type. Topographic effects are modeled for plane wave and magnetic dipole sources. The effects of relief in basement topography on the response of a horizontal loop-loop system are computed and compared with scale-model measurements. CSAMT field data which can not be adequately explained by plane-layered models are analyzed using models with variable layer thickness. The correctness of the theoretical development is verified by comparison with physical measurements. The utility of the theory is illustrated by application to problems which can not be explained by plane-layered models.
26

THE INFLUENCE OF INDUCED POLARIZATION IN INDUCTIVE METHODS OF ELECTRICAL PROSPECTING.

Debroux, Patrick Serge, 1957- January 1985 (has links)
No description available.
27

A model of argumentation and its application in a cooperative expert system

Clark, Peter January 1991 (has links)
No description available.
28

Parsimonious migration 3-C 3-D VSP migration /

Agnihotri, Yogesh, January 2006 (has links)
Thesis (M.S.) -- University of Texas at Dallas, 2006 / Includes vita. Includes bibliographical references (leaves 24-25)
29

Calculating depths to shallow magnetic sources using aeromagnetic data from the Tucson Basin

Casto, Daniel W. January 2001 (has links)
Thesis (M.S.)--University of Arizona, 2001. / Added thesis t.p. Title from HTML title screen (viewed Apr. 25, 2002). Includes bibliographical references.
30

A rolling line source for a seismic sonar /

McClelland, Scott C. January 2002 (has links) (PDF)
Thesis (M.S.)--Naval Postgraduate School, 2002. / Thesis advisor(s): Steven R. Baker, Thomas G. Muir. Includes bibliographical references (p. 63-65). Also available online.

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