NEHRP Clearinghouse

Feasibility Study for a Seismic Drill Bit Location and Guidance System.
Katz, L. J.
National Science Foundation, Washington, DC. Engineering and Applied Science., January 1980, 24 p.
The feasibility of seismically monitoring a rotary drill bit as a means of continuously tracking the location of the bit as it drills into the earth was investigated. A beamsteering array processing technique was used to locate the drill bit. Recorded data is analyzed in a manner similar to that used to locate earthquakes. Results demonstrate that the drill bit generates a unique coherent signal which can be used to locate the bit in the ground. Comparison of results to a conventional method confirms the deviation angle detemined by the new seismic method. This method also supplies azimuthal direction. Benefits to be derived from this study are a reduction in drilling costs for deep wells and a method of providing the driller with information that is needed to reach a traget at depth.
; Rotary drill bits; Seismic detection; Directional drilling; Rotary drilling; Seismic arrays; Azimuth indicators; Position finding