Lesson No. 7: Time-Depth Charts
Published:January 01, 1959
The most universally accepted method of converting travel-times of reflected events to subsurface depths is that embodying the use of the so-called time-depth charts. After a set of reflection records have been studied for traveltimes and what we might term “correlatability,” and after corrections for weathering and low-velocity layer have been applied, the resulting travel-times of the reflections are interpreted in terms of depth by means of such charts.
As a result of what we have learned in our preceding lessons, we are now in a position to discuss the simplest form of these time-depth charts, which is also the most useful and important. If we assume that the reflection has come from a horizontal bed at a depth h with a uniform velocity v, the travel-time t is given, as we have seen, by the relation in which x is the distance from the shot-point to the receiving point.
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Lessons in Seismic Computing
“An elementary text and problem book containing 44 lessons in seismology arranged for selection or combination to cover the normal 36-week course, or for condensation into an 18-week course. The lessons begin without assuming more than secondary school mathematics. An elementary knowledge of calculus is desirable, though not required, for the last half of the book.”