As a result of synthesizing records from continuous velocity logs, the geophysicist 

 will be able to develop better instrumentation for further improving the accuracy 

 and quality of data obtained from seismic surveys. 



From the standpoint of the geologist the velocity log provides another 

 correlation parameter, since the log is derived from a physical property here- 

 tofore not measured in boreholes. Of the various correlation parameters avail- 

 able, it is believed that velocity is the strongest single parameter. The continuous 

 velocity log survey can provide: (1) a log revealing outstanding correlation 

 data; (2) a log which can show small changes in lithologic character; (3) a 

 log for differentiation of stratigraphy in thick limestone, dolomite, sand, and 

 shale sections; (4) a log which can reveal fault contacts under proper conditions; 

 and (5) an effective log in highly saline drilling fluid. 



Further, initial studies indicate that velocity variations within a formation 

 are related to porosity changes and that qualitative and quantitative analyses 

 are possible. 



It is the writers' opinion that the continuous velocity log will be invaluable 

 in supplementing data provided by electrical and radioactive logs, and as the 

 velocity log gains acceptance among geologists and petroleum engineers, the 

 geophysicists will receive the by-product of velocity information at considerably 

 reduced expense. 



Reprinted from The Bulletin of the American Association of Petroleum Geologists 

 v. 41, no. 8, August, 1957, p. 1667-1682. 



BIBLIOGRAPHY 



Hicks, W. G., and Berry, J. E., 1956, Application of continuous velocity logs to determination 

 of fluid saturation of reservoir rocks: Geophysics, v. 21, no. 3, p. 739-754. 



Summers, G. C, and Broding, R. A., 1952, Continuous velocity logging: Geophysics, v. 

 17, no. 3, p. 586-597. 



Wyllie, M. R. J., Gregory, A. R., and Gardner, L. W., 1956, Elastic wave velocities in 

 heterogeneous and porous media: Geophysics, v. 21, no. 1, p. 41-70. 



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