Background subtraction system for pulsed neutron logging of earth boreholes

Patent · Mon Nov 03 23:00:00 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
• Country of Publication: United States
• Language: English

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