Method of radioactive well logging

Patent · Tue Aug 15 04:00:00 EDT 1989

OSTI ID:5394262

Gadeken, L L; Smith, Jr, H D

This patent describes a method for determining the relative amount of a low energy isotope in a steel casing lined well bore relative to the amount of the isotope outside the casing. Wherein the isotope is a relatively low energy gamma ray emitting isotope which tags the liquid phase of fracturing material which has been hydraulically injected from the well bore into the surrounding earth formations and has migrated into the borehole. The method comprising the steps of: detecting the intensity of gamma radiation from the tracer distributed in the borehole and the surrounding earth formations by a gamma ray detector; separating the gamma ray intensity data into an observed energy spectrum of detected gamma rays; obtaining from the observed energy spectrum count rates of gamma radiation in an energy region associated with gamma radiation emitted by relatively low energy tracer in at least two relatively low energy ranges; combining count rates to obtain an observed photoelectric ratio of count rates in the second energy range to count rates in the first energy range; obtaining count rates of radiation in all the energy regions associated with gamma radiation emitted by the low energy tracer and processing the count rates to obtain the total elemental concentration of the low energy tracer in the borehole and the formation; and determining the amount of the low energy tracer in the borehole relative to the amount of the low energy tracer outside the casing from the observed photoelectric ratio of low energy tracer, the total observed concentration of the low energy tracer, and low energy photoelectric ratios calibrated for the tracer in the borehole and in the formation, respectively.

• Assignee: Halliburton Logging Services, Inc., Houston, TX
• Patent Number(s): US 4857729
• Application Number: PPN: US 7184742A
• OSTI ID: 5394262
• 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
COUNTING TECHNIQUES
EXPLORATION
GAMMA LOGGING
GEOLOGIC DEPOSITS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
PETROLEUM DEPOSITS
RADIOACTIVITY LOGGING
RESOURCES
WELL LOGGING