Methods and means for azimuthal neutron porosity imaging of formation and cement volumes surrounding a borehole
A first example azimuthal neutron porosity tool for imaging foiniation and cement volumes surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises one sonde-dependent electronics; a slip-ring and motor section; and a plurality of tool logic electronics and PSUs. An alternative azimuthal neutron porosity tool for imaging formation and cement volumes surrounding a borehole is also provided, the tool including at least a far space detector; a near space detector; and a source located within a moderator shield that rotates around an internal tool axis.
1 . An azimuthal neutron porosity tool for imaging of formation and cement volumes surrounding a borehole, said tool comprising:
an internal length comprising a sonde section, wherein said sonde section further comprises one or more sonde-dependent electronics;
a slip-ring and motor section; and
a plurality of tool logic electronics and PSUs.
2 . The tool of claim 1 , further comprising a multi-azimuthal caliper used to assist in the determination of borehole volume for borehole effect compensation.
3 . The tool of claim 1 , further comprising a far space detector; a near space detector; and a source located within a moderator shield.
4 . The tool of claim 3 , wherein said moderator shield further comprises an epoxied boron.
5 . The tool of claim 3 , wherein said shield further comprises cadmium.
6 . The tool of claim 1 , further comprising a means for rotation that rotates the toot inside a tool housing being driven by a motor.
7 . The tool of claim 6 , wherein the tool rotates such that slip rings are disposed at either end so as to permit through-wiring.
8 . An azimuthal neutron porosity tool for imaging of formation and cement volumes surrounding a borehole, said tool comprising:
a far space detector;
a near space detector;
and a source located within a moderator shield that rotates around an internal tool axis.
9 . The tool of claim 8 , further comprising a source reaction plane that rotates together with said near space and far space detectors.
10 . The tool of claim 8 , wherein said moderators shield further comprise an epoxied boron.
11 . The tool of claim 8 , wherein said shield further comprises cadmium.
12 . The tool of claim 10 , wherein said epoxied boron shield permitts strong directional bias of the output,-thereby enabling deconvolution of the resulting logs.
13 . The tool of claim 11 , wherein said cadmium shield permits strong directional bias of the output, thereby enabling deconvolution of the resulting logs.