Downward Continuation of Bouguer Gravity Anomalies and Residual Aeromagnetic Anomalies by Means of Finite Differences
Issue Date
1975Keywords
airborneanomalies
Bouguer
data processing
depth
determination
finite differences
geophysical methods
geophysical surveys
gravity methodsinterpretationmagnetic methodsmathematical methodsmethodsprogramsresidualsurveysGravity prospecting -- Mathematical modelsMagnetic prospecting -- Mathematical models
Committee Chair
Sturgul, J. R.Metadata
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The University of Arizona.Rights
Copyright © is held by the author. Digital access to this material is made possible by the Antevs Library, Department of Geosciences, and the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author or the department.Collection Information
This item is part of the Geosciences Theses collection. It was digitized from a physical copy provided by the Antevs Library, Department of Geosciences, University of Arizona. For more information about items in this collection, please email the Antevs Library, antevs@geo.arizona.edu.Abstract
The depths to buried bodies, characterized by anomalous gravity and magnetic properties, are determined by a combination of two numerical techniques. An upward continuation integral is solved by a method by Paul and Nagy using elemental squares and low order polynomials to describe the behavior of the gravity or magnetic data between observed data points. Downward continuation of the magnetic or gravity data is done by a finite difference technique as described by Bullard and Cooper. The applicability of the techniques are determined by comparison to depths determined by other means over the same anomalies and by comparison to various rule-of-thumb methods prevalent in the geophysical literature. The relative speed and cost of the particular computer system used is also considered in the applicability. The results show that although the initial costs of the computer program are high, the combined technique is as good as and at times better than the rule-of-thumb methods in determining the depth to the anomaly-causing body and is useful when more than just an approximate depth is of interest.Type
textThesis-Reproduction (electronic)
Degree Name
M.S.Degree Level
mastersDegree Program
Graduate CollegeGeosciences
Degree Grantor
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