ABSTRACT
Factors determining the precision of data procured by the reflection seismograph are discussed under three main headings: (1) under instrumentation, errors caused by various components are considered; (2) under computation, errors introduced by uphole and primary wave computational procedures are discussed as well as those attendant with various plotting methods; and (3) under velocity, numerous vagaries and their potential errors are analyzed. It is concluded that surveys which involve only errors of the first two categories may be accurate to ±50 feet, while those under the third may vitiate the results. The geologist, whose knowledge of stratigraphy may anticipate such velocity variables, can contribute significantly to the precision of the method by a thorough understanding of the ramifications.