Method and apparatus for determining clay counter-ion concentration in shaly sands

Patent · Tue Oct 06 04:00:00 EDT 1987

OSTI ID:5837577

Scala, C

This patent describes a method for determining, in situ, clay counter-ion concentrations in a fluid bearing shaly sand earth formation penetrated by a well borehole, comprising the steps of: (a) detecting in a well borehole at a particular depth level natural gamma radiation emanating from the earth formations penetrated by the borehole as count rate signals. Then separating the detected gamma radiation signals into an energy spectrum of naturally occurring gamma radiation count rate signals as a function of energy and generating signals representative of the energy spectrum of the count rates of naturally occurring gamma radiation at the particular depth level; (b) comparing the representative count rate signals with standard gamma ray energy spectra representative of natural radioactive elements found in the earth formations penetrated by a well borehole. Thereby separating out gamma ray count rates attributable to at least uranium U, thorium Th, and potassium K occurring in the earth formations; (c) measuring the porosity phi of the earth formation at the particular depth level and normalizing the count rates attributable to uranium U and thorium Th at the particular depth level; (d) determining the clay counter ion concentration Q/sub v/ of the earth formations at the particular depth level by using a predetermined functional relationship and obtaining a signal representative of Q/sub v/ at the particular depth level; and, (e) recording the representative clay counter-ion concentration Q/sub v/ signal as a function of borehole depth.

• Assignee: Halliburton Co., Duncan, OK
• Patent Number(s): US 4698500
• OSTI ID: 5837577
• 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
ACTINIDES
ALKALI METALS
CHARGED PARTICLES
CLAYS
COUNTING TECHNIQUES
DESIGN
DETECTION
ELEMENTS
ENERGY SPECTRA
EQUIPMENT
EXPLORATION
EXPLORATORY WELLS
GAMMA DETECTION
GAMMA LOGGING
GEOLOGIC DEPOSITS
IN-SITU PROCESSING
IONS
METALS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NATURAL RADIOACTIVITY
PETROLEUM DEPOSITS
POROSITY
POTASSIUM
PROCESSING
RADIATION DETECTION
RADIOACTIVITY
RADIOACTIVITY LOGGING
RESOURCES
ROCKS
SANDSTONES
SATURATION
SEDIMENTARY ROCKS
SHALES
SIGNALS
SPECTRA
THORIUM
URANIUM
WELL LOGGING
WELL LOGGING EQUIPMENT
WELLS