Background subtraction system for pulsed neutron logging of earth boreholes

Patent · Tue Nov 04 00:00:00 EST 1980

OSTI ID:6433009

Hertzog, R C

The composition of an earth formation is investigated by repetitively irradiating the formation with bursts of fast neutrons and generating an inelastic energy spectrum from gamma ray counts detected during first time intervals which are contemporaneous with the bursts. A second energy spectrum is generated from gamma ray counts detected during second time intervals which immediately follow respective first time intervals. Gamma ray counts comprising the second spectrum are thereafter subtracted from the gamma ray counts comprising the inelastic spectrum to provide an inelastic energy spectrum with reduced background.

• Assignee: Schlumberger Technology Corp
• Patent Number(s): US 4232220
• OSTI ID: 6433009
• Resource Relation: Patent File Date: Filed date 4 May 1979
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
47 OTHER INSTRUMENTATION
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
NEUTRON-GAMMA LOGGING
BACKGROUND RADIATION
OIL WELLS
BOREHOLES
FAST NEUTRONS
BARYONS
CAVITIES
ELEMENTARY PARTICLES
FERMIONS
HADRONS
NEUTRON LOGGING
NEUTRONS
NUCLEONS
RADIATIONS
RADIOACTIVITY LOGGING
WELL LOGGING
WELLS
020200* - Petroleum- Reserves
Geology
& Exploration
440400 - Well Logging Instrumentation
400103 - Radiometric & Radiochemical Procedures- (-1987)