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Contents Preface xReferences 505Index 509Downloaded 06/25/14 to 134.153.184.170. Redistribution subject to SEG license or copyright; see Terms of Use at http://library.seg.org/ Preface A number of geophysics texts (including our own) provide problems, but few furnish solutions to the problems. Thus students (and professors) who struggle with the problems but do not work them out for themselves miss many of the benefits of the problems. This work is our attempt to partially remedy this situation. This volume was begun to furnish solutions for the problems in the first edition of Exploration Seismology by Sheriff and Geldart; however, that project was never completed. After the second edition appeared in 1995, we revived and expanded the project to provide solutions not only for the problems in Exploration Seismology but also for additional problems. Our intention is to provide a stand-alone volume independent of Exploration Seismology which can be used with whatever textbooks professors and students are using. To this end many problems provide a brief summary of the basic theory required to solve the problem. These "backgrounds" should be regarded as an aide memoires only since they are not intended to develop the subject rigorously or in detail.Although this volume is independent of Exploration Seismology, we expect that a number of our readers will be using that text, and therefore we have organized and numbered the problems so as to be generally compatible with it; we have also used the same mathematical conventions and symbols (with a few exceptions).Measurements of time, fundamental in exploration seismology, are usually made to the nearest millisecond, but in some of the problems a precision of 10 ms or even less is used, especially when measurements on graphs are involved. Graphical solutions were generally obtained from plots on sheets of graph paper large enough to achieve the required accuracy, but the plots included here are, of necessity, reduced in sizes.A list of references cited is located at the end of the book. Terms which are in effect being defined have been italicized. The authors wish to acknowledge the generous assistance of Michael K. Fenwick in the preparation of this book.We invite readers to advise us of errors and faulty derivations or interpretations and also to send us alternative solutions or interpretations.L. P. Geldart R. E. Sheriffx Downloaded 06/25/14 to 134.153.184.170. Redistribution subject to SEG license or copyright; see Terms of Use at http://library.seg.org/ Problems in Exploration Seismology and their Solutionswhat quantities or factors must be considered in arriving at the correct answer. Thirdly, we must consider the available information from which the answer is to be deduced. Some of the available data may not be relevant. Finally, we must determine how the relations between the various factors can be used to get from the starting point to the final goal, that is, the path that must be followed. We should plan how to obtain the solution. Often a diagram will help to u...

The Fourier transform formula for a two‐dimensional fault truncating a horizontal bed at an arbitrary angle of inclination is derived. The amplitude spectrum of the Fourier transform is found to give information about the depth to the top of the upper part of the faulted bed and the inclination of the fault‐plane. Under suitable conditions the thickness and the displacement of the bed involved can be obtained. With actual field data, these transforms can be obtained at discrete points by a Fourier analysis of the gravity anomaly. A field example from the Logan fault area near Montreal, Que., Canada, is given.

A simplified formula is given for the gravity effect of a horizontal semi‐infinite block truncated by a dipping plane. This formula is used to obtain curves illustrating the gravity anomalies for blocks having different thicknesses and depths truncated by planes dipping at various angles. By combining two blocks, results are obtained for faulted horizontal beds for a wide range of bed thicknesses and depths, fault displacements and dips. These should be useful as guides in interpreting fault anomalies, and in planning gravity programs intended to map faults. The most striking feature of the curves is the marked effect of the dip of the fault plane on the curves for faulted beds. The asymmetry of the fault curves is related mainly to the dip and can be used to determine dips between 30 and 90 degrees. If the dip of the fault, density contrast, and bed thickness are known, the depths to the bed on the two sides of the fault are given by the sizes and positions of the gravity maximum and minimum.

A n analogue method was used to cornpute t h e poxvcr spectra of three orthogonal micropulsation components recordecl a t M o n t St. I-Iilaire, Quebec, Canada the X and I' components changes \\,ith period. Thus, information concerning the distribution of energy among the three components is important and cannot be obtained from either of these methods.An analogue computer \\-as used for statistical computation. Paper chart records are irnportailt in order to observe how the period varies from cycle to Canadian Journal of Physics. Volume 45 (1967) 3743 Can. J. Phys. Downloaded from www.nrcresearchpress.com by University of Tennessee on 12/28/14For personal use only.