Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
182 words
A borehole-while-drilling tool for measuring characteristics of earth formations surrounding a borehole including a tubular body having upper and lower ends adapted for coupling to a drill string and providing a fluid flow path between its upper and lower ends, said tubular body having a tubular outer radius and a source of neutrons disposed coaxially within said body, and a plurality of longitudinally spaced secondary radiation detectors carried by said tool with means responsive to said longitudinally spaced radiation detectors to generate first signals useful for determining a first characteristic of said earth formations, wherein said tool is characterized by a plurality of stabilizer blades secured symmetrically about the outer periphery of said tubular body, a plurality of detector cavities in registration with each of said stabilizer. blades, each of said cavities formed by an outwardly facing slot of said body which faces an inwardly facing slot of a stabilizer blade, each of said cavities having an outer radial extent substantially greater than said nominal tubular outer radius, and each of said secondary radiation detectors being placed within one of said cavities.
Claim 2
Dependent Claim
158 words
The tool of claim 1 having a gamma ray source positioned within said body and at least one gamma ray detection assembly carried by said body and means responsive to said at least one gamma ray detection assembly to generate second radiation signals useful for determining a second characteristic of said earth formations, wherein said tool is further characterized by a second plurality of stabilizer blades disposed about the outer periphery of said tubular body, each of said second plurality of stabilizer blades extending radially outwardly from said tubular body at a second maximum radial distance, and said at least one gamma ray detection assembly is associated with at least one of said second plurality of stabilizer blades, each gamma ray detection assembly placed radially at least partially beyond said nominal outer radius of said tubular wall of said body in an associated gamma ray detection cavity, said gamma ray detection cavity extending radially into an associated blade.
Claim 3
Dependent Claim
58 words
The tool of claim 1 or claim 2 further characterized by means including ultrasonic sensor means carried by said body for producing standoff signals representative of standoff of said body from said borehole while drilling said borehole, wherein signals used to measure characteristics of earth formations may be corrected as a function of measured standoff of said body.
Claim 4
Dependent Claim
16 words
The tool of claim 1 or 2 wherein said first characteristic of earth formations is porosity.
Claim 5
Dependent Claim
20 words
The tool of claim 2 or 4 wherein said second characteristic of earth formation is density or photoelectric absorption coefficient.
Claim 6
Dependent Claim
39 words
The tool of claim 1 further characterized by each of said blades having a longitudinal length and an angular width dimension such that the angular width of each blade is substantially less than the angular distance between each blade.
Claim 7
Dependent Claim
71 words
The tool of claim 3 further characterized by said ultrasonic means including at least one ultrasonic sensor disposed in at least one of said second plurality of stabilizer blades, said ultrasonic sensor facing radially outwardly from said tubular body, and means for combining radiation signals with said standoff signals to correct a measurement of a characteristic of said earth formations for the effect of standoff of said tool from said borehole.
Claim 8
Dependent Claim
34 words
The tool of claim 7 further characterized by said one blade of said second plurality of stabilizer blades is a blade other than a blade in which a gamma ray detection assembly is disposed.
Claim 9
Dependent Claim
66 words
The tool of claim 7 further characterized by means for generating borehole diameter signals from said ultrasonic sensor indicative of the diameter of said borehole opposite said tool, means for combining said standoff signals with said fist signals to correct said first formation characteristic, and means for combining said borehole diameter signals with said second radiation signals to correct said second characteristic of said earth formations.
Claim 10
Dependent Claim
60 words
The tool of claim 2 further characterized by said stabilizer blade in which said at least one gamma ray detection assembly is associated includes a plug of substantially gamma ray transparent material adjacent said gamma ray detection assembly, and said tubular body includes a path of substantially gamma ray transparent material through its wall adjacent said gamma ray detection assembly.