Patent ID: 6678616
Filing Date: 2004-01-13
Classification: G01V

Abstract:
A method for producing a velocity image data set representing formation surrounding a borehole, the method comprising the steps of:a) transmitting an ultrasonic pulse through the wall of said borehole such that by refraction said ultrasonic pulse travels in said formation along said borehole; b) receiving said ultrasonic pulse at first and second receivers spaced-apart in a direction along said borehole; c) producing a velocity image data value indicative of difference of arrival times of said ultrasonic pulse at said first and second receivers; d) repeating steps a)-c) at a plurality of azimuths to produce a velocity image data value at each of the plurality of azimuths; and e) repeating steps a)-d) at a plurality of depths in the borehole to produce a velocity image data set.