An interpretation routine
Published:January 01, 1980
One of the well-known shortcomings of the seismic refraction method is the disproportionate length of time required to produce final detailed results, when compared with the time taken to acquire data. Processing is not a major problem because digital computers and plotters facilitate rapid computation and presentation of results (Peraldi and Clement, 1972; Scott, 1973). Most delays occur in the interpretation phase, which requires high levels of expertise and judgment (Dobrin, 1976, p. 294).
In the majority of refraction interpretation routines (e.g., Hawkins, 1961, p. 811, 812), processing follows interpretation of data. This procedure is adequate when there are only a few spreads to interpret or when the processing facilities are convenient. However, when there are large amounts of data, or when consistency with cross-lines or drillholes is required, then reprocessing following each reinterpretation may be inconvenient as well as costly.
With the GRM, the interpretation routine involves examination of both the basic traveltime data and the processed data, viz., the velocity analysis functions and time-depths, in order to recognize optimum XY-values, surface irregularities, etc. Therefore, for the most efficient use of the GRM, the interpretation phase should follow the data processing phase. The interpretation phase then requires an editing phase, where meaningless computations are removed from further consideration.
Processing using the GRM is best carried out using a computer and plotter because of the large number of points produced when a range of XY-values is used. A program has been published by Hatherly (1976) for the processing and plotting of seismic refraction
Figures & Tables
The Generalized Reciprocal Method of Seismic Refraction Interpretation
“In this monograph, the author describes a new comprehensive method of interpretation, the generalized reciprocal method (GRM), for which many of the previously presented methods are special cases. It also has the advantage of combining many of the better features of the individual methods.”