Tubular azimuthal gamma ray tool and applications thereof

Abstract

A gamma ray measurement tool has a tubular shell, a gamma ray detector disposed in the tubular shell, and a shield disposed between the tubular shell and the gamma ray detector. The gamma ray detector has a scintillation crystal coupled to a photomultiplier tube, and the shield has a open window configured to allow gamma rays to pass through and reach the scintillation crystal. Further, the tubular shell has a first axis in the longitudinal direction, and the gamma ray detector has a second axis in the longitudinal direction, the first axis and the second axis do not coincide with each other, and a distance between the scintillation crystal and an inner surface of the tubular shell through the window is shorter than a distance between the scintillation crystal and a portion of the tubular shell covered by the shield.

Dependencies are inferred from the claim text.