Method and apparatus for determining aluminum concentration in earth formations
AssigneeBaker Hughes Incorporated
InventorsRichard R. Pemper, Pingjun Guo
Life of this patent
Estimating the term…
Abstract
Elemental analysis of an earth formation (including Aluminum) is obtained using measurements from a gamma ray logging tool. The inelastic spectrum of Aluminum is determined from measurements made in a water tank. From the elemental analysis, an estimate of the mineralogy of the formation is made treating the problem as one of Linear Programming (maximizing an objective function subject to equality and/or inequality constraints.
Claims22
A method of analyzing an earth formation, the method comprising:
- a) conveying a tool into the earth formation;
- b) irradiating the formation with the tool;
- c) detecting gamma rays resulting from interaction of the irradiation of the formation;
- and
- d) using an inelastic spectrum of Aluminum (Al) for estimating from a spectrum of the gamma rays an elemental concentration of Al in the formation.
An apparatus for evaluating an earth formation, the apparatus comprising:
- a) a tool configured to be conveyed in a borehole in the earth formation, the tool including:
- (A) a radiation source configured to irradiate the earth formation, and
- (B) at least one detector configured to detect gamma rays resulting from interaction of the irradiation with the earth formation;
- and b) a processor configured to:
- (C) determine a spectrum of the detected gamma rays, and
- (D) use an inelastic spectrum of aluminum (Al) to estimate from the determined spectrum an elemental concentration of Al in the formation.
A computer readable medium used with an apparatus for evaluating an earth formation, the apparatus comprising:
- a) a tool configured to be conveyed in a borehole in the earth formation, the tool including:
- (A) a radiation source configured to irradiate the earth formation, and
- (B) at least one detector configured to detect gamma rays resulting from interaction of the irradiation with the earth formation;
- the medium comprising instructions which enable a processor to
- (b) determine a spectrum of the detected gamma rays;
- and
- (c) use an inelastic spectrum of aluminum (Al) to estimate from the determined spectrum an elemental concentration of Al in the earth formation.
Dependencies are inferred from the claim text.