Formation density logging using multiple detectors and sources

Patent · Tue Jun 24 04:00:00 EDT 1986

OSTI ID:5401314

Coope, D F

A device is described for use in a borehole traversing an earth formation comprising: gamma ray emitting means the means emitting collimated gamma ray beams along a first set of at least three trajectories, the trajectories projecting in an azimuthally symmetric pattern about the longitudinal axis of the device, intersecting at a first point on the axis of the device, and intersecting a first circle located in a sample of the formation to be measured; first gamma ray detecting means oriented to receive emitted gamma rays scattered from at least three locations within the formation sample along a second set of at least three trajectories, the trajectories projecting in an azimuthally symmetric pattern about the axis of the device intersecting a second point on the axis of the device and intersecting the first circle; and means for determining a first product of the counting rates of gamma rays received by the first detecting means from each of the at least three trajectories as scattered from each of the at least three locations within the formation sample. The first product is indicative of the average density of the formation sample.

• Assignee: NL Industries, Inc., New York, NY
• Patent Number(s): US 4596926
• OSTI ID: 5401314
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
440101 -- Radiation Instrumentation-- General Detectors or Monitors & Radiometric Instruments
440400 -- Well Logging Instrumentation
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
47 OTHER INSTRUMENTATION
AZIMUTH
BOREHOLES
CAVITIES
DENSITY
DETECTION
EQUIPMENT
GAMMA DETECTION
GAMMA-GAMMA LOGGING
GEOLOGIC DEPOSITS
MEASURING INSTRUMENTS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
PETROLEUM DEPOSITS
PHYSICAL PROPERTIES
RADIATION DETECTION
RADIATION DETECTORS
RADIOACTIVITY LOGGING
RESERVOIR ROCK
RESOURCES
SCATTERING
SYMMETRY
TRAJECTORIES
WELL LOGGING
WELL LOGGING EQUIPMENT