Method of acoustic ranging
AssigneeSchlumberger Technology Corporation
InventorGraham A. McElhinney
Life of this patent
Estimating the term…
Abstract
An acoustic surveying method includes computing at least one of a distance and direction between first and second subterranean boreholes. An acoustic pulsed is transmitted into a subterranean formation from the first borehole and received at three or more spaced receivers deployed in the second borehole. A distance between the two boreholes may be determined using longitudinally spaced receivers while a toolface to target direction (angle) may be determined using circumferentially spaced receivers.
Claims19
A method for surveying a subterranean borehole, the method comprising:
- (a) deploying an acoustic transmitter in a first borehole;
- (b) deploying first, second, and third longitudinally spaced acoustic receivers in a second borehole;
- (c) firing the acoustic transmitter to launch an acoustic pulse;
- (d) receiving corresponding acoustic waveforms at each of the first, second, and third acoustic receivers;
- and
- (e) processing the acoustic waveforms received in (d) in combination with at least one longitudinal spacing between the first, second, and third acoustic receivers to compute first and second pole angles;
- and
- (f) processing the first and second pole angles computed in (e) to further compute a distance between the first borehole and the second borehole.
A method for surveying a subterranean borehole, the method comprising:
- (a) deploying an acoustic transmitter in a first borehole;
- (b) deploying first, second, and third circumferentially spaced acoustic receivers in a second borehole;
- (c) firing the acoustic transmitter to launch an acoustic pulse;
- (d) receiving corresponding acoustic waveforms at each of the first, second, and third acoustic receivers;
- and
- (e) processing the acoustic waveforms received in (d) to determine a toolface to target angle between the first and second boreholes.
A method for surveying a subterranean borehole, the method comprising:
- (a) deploying an acoustic transmitter in a first borehole;
- (b) deploying at least first and second sets of longitudinally spaced acoustic receivers in the second borehole, each of the first and second sets of acoustic receivers including corresponding first, second, and third circumferentially spaced acoustic receivers;
- (c) firing the acoustic transmitter to launch an acoustic pulse;
- (d) receiving corresponding acoustic waveforms at each of the first and second sets of acoustic receivers;
- and
- (e) processing the acoustic waveforms received in (d) to determine at least first and second toolface to target angles between the first and second boreholes.
Dependencies are inferred from the claim text.