AZIMUTHAL CEMENT DENSITY IMAGE MEASUREMENTS
First Claim
Patent Images
1. A method for generating a cement density image in a cemented borehole, comprising:
- positioning a logging tool inside the borehole at a selected depth, wherein the logging tool comprises a gamma ray source, a short-spaced detector positioned ≦
7 inches from the source, and a long-spaced detector positioned less than 12 inches but farther than the short-spaced detector from the source; and
measuring gamma ray count rates at each detector and using them to calculate an estimated cement thickness or density.
0 Assignments
0 Petitions
Accused Products
Abstract
Well logging method and logging tool for measuring cement density and thickness at different azimuth angles for a cemented, cased well. The method uses a gamma source, a short-spaced detector, a long-spaced detector, and preferably a backscatter detector, where the detector-to-source spacings are designed for calculating (93) thickness and density of the cement annulus (94) from the detector count rates (91).
28 Citations
22 Claims
-
1. A method for generating a cement density image in a cemented borehole, comprising:
-
positioning a logging tool inside the borehole at a selected depth, wherein the logging tool comprises a gamma ray source, a short-spaced detector positioned ≦
7 inches from the source, and a long-spaced detector positioned less than 12 inches but farther than the short-spaced detector from the source; andmeasuring gamma ray count rates at each detector and using them to calculate an estimated cement thickness or density. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A nuclear density logging tool for cemented borehole use, for estimating cement density or thickness, comprising:
a tool body adapted to be lowered longitudinally into a casing in a cylindrical borehole along the borehole axis, said tool body housing a gamma ray source, a short-spaced detector and a long-spaced detector, all fixed to the tool body and spaced in the longitudinal direction such that the short-spaced detector is positioned ≦
7 inches from the source and the long-spaced detector is positioned less than 12 inches from the source but farther than the short-spaced detector.- View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22)
Specification