Patent ID: 9267359
Filing Date: 2016-02-23
CPC Classification: E21B,G01F,G01V

Claim Text:
1. A method of investigating a subterranean wellbore comprising: a. providing a downhole tool having a radiation source; b. disposing the downhole tool in the subterranean wellbore; c. directing radiation from the source into an annulus between the downhole tool and a wall of the subterranean wellbore so that the radiation scatters back to a detector on the downhole tool; d. detecting radiation that single scattered back into the detector from the annulus; e. identifying a material in the annulus based on a count rate of detected radiation; and f. repeating steps (a)-(c) at a different depth in the wellbore and where a thickness of the annulus varies around a circumference of the annulus, so that a detectable amount of energy of the at least some of the radiation is attenuated within an outer tubular that circumscribes the annulus.