Matches 1 - 50 out of 114 1 2 3 >
Match Document Document Title
7482579 Method and apparatus for high resolution gamma ray measurements  
A method for measuring radiation, the method includes selecting at least two radiation detectors, each detector having a spatial resolution that differs from the spatial resolution of other...
7279677 Measuring wellbore diameter with an LWD instrument using compton and photoelectric effects  
A method for determining the diameter of a wellbore, the wellbore being drilled by a drill string immersed in weighted mud, the weighted mud having a significant weight fraction of a heavy...
7159672 Mapping tool for tracking and/or guiding an underground boring tool  
A portable mapping tool for use in a horizontal drilling system and associated methods use a boring tool configured for transmitting a locating signal. The mapping tool also includes at least one...
7129477 Method of processing data from a dual detector LWD density logging instrument coupled with an acoustic standoff measurement  
A logging-while-drilling density sensor includes a gamma ray source and at least two NaI detectors spaced apart from the source for determining measurements indicative of the formation density. An...
7099503 Image reconstruction method and X-ray CT apparatus  
For the purpose of reducing artifacts caused by a scan plane tilted with respect to a rotation plane when a multi-row detector is employed, a j-th detector row which an X-ray passing through a...
7085405 Direct tomographic reconstruction  
A method of reconstructing tomography images comprising: acquiring data on individual radiation events; distributing a weight of the individual radiation events along a line of flight associated...
7080698 Mapping tool for tracking and/or guiding an underground boring tool  
A portable mapping tool for use in a horizontal drilling system and associated methods use a boring tool configured for transmitting a locating signal. The mapping tool also includes at least one...
6918293 System and method having radiation intensity measurements with standoff correction  
We disclose density measurement methods that are accurate over an extended range of standoff distances. One method embodiment includes: a) obtaining a standoff distance, a near detector count rate,...
6732059 Ultra-low background gas-filled alpha counter  
A method and counter for reducing the background counting rate in gas-filled alpha particle counters wherein the counter is constructed in such a manner as to exaggerate the differences in the...
6696362 Method for using an in situ particle sensor for monitoring particle performance in plasma deposition processes  
Methods are provided for identifying root causes of particle issues and for developing particle-robust process recipes in plasma deposition processes. The presence of in situ particles within the...
6124590 Method for determining thermal neutron capture cross-section of earth formations using measurements from multiple capture gamma ray detectors  
A method for determining thermal neutron capture cross-section of an earth formation penetrated by a wellbore from counts of capture gamma rays detected at spaced apart locations from a source...
5705812 Compaction monitoring instrument system  
An apparatus and method for detecting the location of subsurface markers in a formation proximate to a borehole. The apparatus includes marker detectors in a housing having at least two housing...
5591967 Method and apparatus for determining neutron detector operability using gamma ray sources  
The invention relates to an apparatus and method for verifying the operability of neutron detectors and associated pulse generating circuits in a neutron logging tool prior to committing the tool...
5536938 Pulsed neutron decay logging  
A borehole logging tool having a pair of spaced-apart detectors records intensity signals representing the die-away of nuclear radiation in a subsurface formation. Weighted moments of the intensity...
5530243 Formation density well logging tool with detector array for compensation of wellbore roughness and tool tilt  
A method for determining density of a formation. The method includes irradiating the formation with gamma rays having energy consistent with Compton scattering. Gamma rays are measured at axially...
5528030 System for determining gas saturation of a formation and a wellbore through casing  
A system for determining formation gas saturation in a cased wellbore which includes a neutron logging tool having a source, a first neutron detector offset towards the wellbore primarily sensitive...
5525797 Formation density tool for use in cased and open holes  
An improved formation density logging tool is provided that is effective in cased holes. The improved tool utilizes three detectors: a first detector for primarily compensating for the casing; a...
5461909 Oxygen activation method for quantitative water flow measurements within and behind well bore casing  
A method for measuring the linear flow velocity, radial position, direction, and the flow rate of water flowing within and behind a well borehole casing. A logging tool containing a source of...
5459314 Method for correcting density measurements that are affected by natural and neutron-induced gamma radiation  
A method for measuring formation density corrected for activated gamma radiation. The formation adjacent the borehole is irradiated with low energy gamma radiation from a density tool source. At...
5408097 Method and apparatus for correcting natural gamma ray measurements for borehole fluid effects  
A method and apparatus for detecting natural gamma-ray signals of an earth formation and correcting these gamma-ray signals for effects from borehole gamma-rays. Gamma-ray signals are detected at...
5397893 Method for analyzing formation data from a formation evaluation measurement-while-drilling logging tool  
A method for analyzing data from a measurement-while-drilling (MWD) formation evaluation logging tool which compensates for rotation of the logging tool (along with the rest of the drillstring)...
5357797 Method and apparatus for correcting MWD porosity measurement  
A porosity measuring MWD system utilizing a source and two detectors is set forth. The source and two detectors are preferably mounted in a stabilizer fin on a drill collar. A standoff measuring...
5350925 Methods for determining values for earth formation properties  
Methods are provided for processing spectral data detected by a gamma ray detector of a borehole tool in order to obtain quantitative determinations of formation and/or borehole properties....
5345077 Method and apparatus for producing a porosity log of a subsurface formation corrected for detector standoff  
A borehole logging tool is lowered into a borehole traversing a subsurface formation and a neutron detector measures the die-away of nuclear radiation in the formation. A model of the die-away of...
5272336 Temperature corrections of measurements made with scintillation detectors  
This disclosure sets out a method for applying a temperature correction to calculations that employ measurements made with scintillation detectors. Temperature measurements are made at or near the...
5175429 Stand-off compensation for nuclear MWD measurement  
The present invention relates generally to increasing the accuracy of MWD nuclear based measurement systems. Specifically, the present invention provides a secondary measurement system for...
5097123 Broad energy spectra neutron source for logging and method  
Logging method and tool string for identifying and determining the concentrations of subsurface formation elements next to a borehole, by (i) using a broad energy spectra neutron source (such as a...
5065016 Radioactive well logging to determine vertical brine flow  
Brines in earth formations in the vicinity of a well borehole are bombarded with neutrons. The neutrons are slowed to thermal energy and captured by sodium atoms in the brine according to the...
5055675 Pulse height analyzer for spectroscopy thermal multigate decay well logging system  
A pulse height analyzer for spectrocopy thermal multigate decay well logging systems is disclosed and has an input section comprising a peak time determining circuit locating a peak occurrence. The...
5055676 Method for determining oil and water saturation in earth formation surrounding a borehole  
A method and an apparatus for determining the hydrocarbon saturation S o in an earth formation surrounding a borehole, and/or the hydrocarbon saturation C b in said borehole, comprising:...
5021653 Geochemical logging apparatus and method for determining concentrations of formation elements next to a borehole  
Logging method and tool string for identifying and determining the concentrations of subsurface formation elements next to a borehole, by (i) using a low energy neutron source (either a chemical...
5019708 Method for eliminating the effect of rugosity from compensated formation logs by geometrical response matching  
A method for determining the compensated density of a subsurface geological formation wherein the effect of borehole rugosity is reduced or eliminated utilizes the differences in the vertical...
4982086 Method of porosity determination in porous media by x-ray computed tomography  
A method for porosity determination in porous media such as earth and rock core samples by x-ray computed tomography in which a sample of the porous medium is scanned after saturation with a first...
4926044 Thermal decay time logging method and apparatus  
A novel neutron burst timing, detection, and calculation method and apparatus are disclosed for a Thermal Decay Time Logging System. A neutron bursting regime is provided which includes a short...
4910397 Pulsed neutron porosity logging  
A borehole logging tool employing a pulsed neutron source and a pair of spaced-apart epithermal neutron detectors is lowered into a borehole traversing a subsurface formation. The formation is...
4894534 Logging apparatus and method  
Downhole measuring apparatus includes a gamma radiation source and at least two pairs of radiation detectors carried by a housing so that radiation may be emitted from the source and scattered by...
4705944 Formation density logging while drilling  
A gamma ray density sub and method useful for measurement-while-drilling applications utilizing a gamma ray source and detector located on the rotating sub and computation of the product of the...
4698501 System for simultaneous gamma-gamma formation density logging while drilling  
A system for logging subterranean formations for the determination of formation density by using gamma radiation. Gamma ray source and detection means are disposed within a housing adapted for...
4697078 Method for quality control of counting logs  
A generalized computer-based system and method for acquisition of nuclear well logging data. A feature of the present invention is the ability to provide time distribution spectra over the entire...
4668863 Neutron logging time spectral data acquisition system and method  
A generalized computer-based system and method for acquisition of nuclear well logging data, including downhole generation of spectral information. A downhole instrument traverses a borehole...
4656354 Method for induced gamma ray logging  
A generalized computer-based system and method for acquisition of nuclear well logging data. A feature of the present invention is the ability to provide time distribution spectra over the entire...
4645927 Clay type and volume evaluation  
Methods for the determination of clay types and/or clay volumes of an earth formation are disclosed. Information as to the hydroxyl type of the clay minerals is obtained from the difference between...
4638158 Gamma ray measurement of earth formation properties using a position sensitive scintillation detector  
A well logging system for measuring the radial density distribution of earth formations in the vicinity of a well borehole is provided. The system utilizes a single position sensitive gamma ray...
4604522 Method and apparatus for logging a borehole employing dual radiation detectors  
The disclosure relates to a method and apparatus for logging a borehole. A sonde having a source of penetrating radiation and at least two longitudinally-spaced radiation detectors is passed within...
4524273 Method and apparatus for gamma ray well logging  
A radioactive logging source carried by a logging tool injects gamma rays into the formation. A detector generates a pulse for each gamma ray incident upon the detector having an amplitude...
4423323 Neutron logging method and apparatus for determining a formation characteristic free of environmental effects  
A method for determining porosity or other formation characteristic of a sub-surface geological formation traversed by a borehole is claimed. A neutron logging tool is passed through the borehole...
4302669 Neutron thermalization time logging  
Method and apparatus for pulsed neutron logging employing detectors of different energy-dependent sensitivities to neutrons at energy levels less than the chemical binding energy of hydrogen in...
4283624 Epithermal neutron decay logging  
Method and apparatus for epithermal neutron decay logging wherein the formation under investigation is irradiated with bursts of fast neutrons which are moderated therein to form a population of...
4266126 Pulsed radiation decay logging  
Methods and apparatus for radioactive well logging in which the formation is irradiated with bursts of primary radiation and the resulting secondary radiation is measured during a plurality of time...
4251724 Method and apparatus for determination of temperature, neutron absorption cross section and neutron moderating power  
A nuclear method and apparatus determines the temperature of a medium by injecting fast neutrons into the medium and detecting returning slow neutrons in three first energy ranges by producing...
Matches 1 - 50 out of 114 1 2 3 >