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THE RESPONSE OF VELOCITY‐SENSITIVE WELL GEOPHONES *
- Source: Geophysical Prospecting, Volume 8, Issue 1, Apr 1960, p. 68 - 84
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- 27 Apr 2006
Abstract
Abstract
The factors affecting the response of a velocity‐sensitive well geophone are discussed and it is shown that the geophone movement in response to a seismic pulse is primarily due to the pressure difference between its ends. Several practical examples are calculated to show that the first arrival waveform recorded by a geophone depends on the distance from an interface and that these changes in recorded waveform may give errors of up to 3 msec in well‐velocity surveys. These errors may be minimised by using pressure geophones or by avoiding measurements at geological interfaces.