US3930153A
Expired / Lapsed
US
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Measurement of subsurface formation lithology, including composition and fluids, using capture gamma spectroscopy
Assignee: Texaco Inc
•
Filing: 1974-12-12
•
Granted: 1975-12-30
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Expires: 1994-12-12
Abstract
Abstract Gamma ray spectra of earth formations surrounding an open or cased well borehole are obtained by exciting subsurface formation elements around the borehole with neutrons and detecting the gamma ray resulting from capture in the subsurface formation of thermalized neutrons from a capture gamma spectroscopy (C.G.S.) well log source. The spectra of gamma rays so obtained are analyzed to form logs of the elements which contribute significantly to the spectra. From these logs, quantitative measurements of the primary formation parameters of formation water salinity, water saturation, porosity, major matrix components and ratios of formation constituents of the earth formations are obtained.
Inventors
- 👤 Hubert D Scott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:33
CPC Classifications
G; G01; G01V; G01V5/00; G01V5/04; G01V5/08; G01V5/10; G01V5/101; G01V5/102
Claims Analysis
Total Claims: 64
Claim 1
Independent Claim
158 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture crosssection of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining quantitatively the primary formation parameters of the formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 2
Independent Claim
158 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture crosssection of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining quantitatively the primary formation parameters of the formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 3
Dependent Claim
38 words
The method of claim 1, further including the step of: obtaining the macroscopic thermal neutron capture cross-section of the formation surrounding the borehole with a separate logging tool prior to said step of obtaining gamma ray energy spectra.
Claim 4
Dependent Claim
54 words
The method of claim 1, wherein: a. said step of bombarding the earth formation with high energy neutrons comprises bombarding the formation with repetitive pulses of fast neutrons; and b. compensating the unknown gamma ray spectrum for variations in the thermal neutron capture cross-section of materials present in the earth formations surrounding the borehole.
Claim 5
Dependent Claim
25 words
The method of claim 1, wherein: said step of bombarding the earth formation with high energy neutrons comprises continuously bombarding the formation with fast neutrons.
Claim 6
Dependent Claim
26 words
The method of claim 1, further including the step of: forming a record of the obtained quantitative primary formation parameters as a function of borehole depth.
Claim 7
Dependent Claim
26 words
The method of claim 1, wherein: said step of obtaining gamma ray spectra is performed during a single pass of said neutron source through the borehole.
Claim 8
Independent Claim
157 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the water saturation of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 9
Independent Claim
157 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the water saturation of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 10
Dependent Claim
35 words
The method of claim 7, further including the step of: obtaining the porosity of the formation from the quantitative estimate of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 11
Dependent Claim
38 words
The method of claim 7, further including the step of: obtaiNing the salinity of water in the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 12
Dependent Claim
40 words
The method of claim 7, further including the step of: obtaining the volume fractions of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 13
Dependent Claim
39 words
The method of claim 7, further including the step of: obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 14
Dependent Claim
91 words
The method of claim 7, wherein: a. said step of obtaining gamma ray spectra of unknown materials comprises the step of obtaining formation gamma ray spectra for plural depths in the borehole; and b. said step of comparing comprises the step of comparing gamma ray spectra of unknown materials for each of plural depths in the borehole with the standard spectra; and c. said step of obtaining the water saturation of the formation comprises the step of obtaining the water saturation of the earth formations at plural depths in the borehole.
Claim 15
Dependent Claim
59 words
The method of claim 12, and furhter including the steps of: a. selecting a depth in the borehole as being water saturated based on the water saturation value obtained during said step of deriving water saturation; and b. obtaining enhanced water saturation values for other depths of the borehole based on the water saturation value at the selected depths.
Claim 16
Dependent Claim
58 words
The method of claim 12, and further including the steps of: a. selecting a depth in the borehole as being water saturated based on the water saturation value obtained during said step of deriving water saturation; and b. obtaining enhanced salinity values for other depths of the borehole based on the water saturation value at the selected depth.
Claim 17
Dependent Claim
58 words
The method of claim 12, and further including the steps of: a. selecting a depth in the borehole as being water saturated based on the water saturation value obtained during said step of deriving water saturation; and b. obtaining enhanced porosity values for other depths of the borehole based on the water saturation value at the selected depth.
Claim 18
Dependent Claim
61 words
The method of claim 12, and further including the steps of: a. selecting a depth in the borehole as being water saturated based on the water saturation value obtained during said step of deriving water saturation; and b. obtaining enhanced volume fractions of formation constituents for other depths of the borehole based on the water saturation value at the selected depth.
Claim 19
Dependent Claim
60 words
The method of claim 12, and further including the steps of: a. selecting a depth in the borehole as being water saturated based on the water saturation value obtained during said step of deriving water saturation; and b. obtaining enhanced ratios of formation components for other depths of the borehole based on the water saturation value at the selected depth.
Claim 20
Dependent Claim
22 words
The method of claim 7, further including the step of: forming a record of water saturation as a function of borehole depth.
Claim 21
Independent Claim
158 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the salinity of water in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 22
Independent Claim
158 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the salinity of water in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 23
Dependent Claim
35 words
The method of claim 19, further including the step of: obtaining the porosity of the formation from the quantitative estimate of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 24
Dependent Claim
40 words
The method of claim 19, further including the step of: obtaining the volume fractions of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 25
Dependent Claim
39 words
The method of claim 19, further including the step of: obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 26
Dependent Claim
93 words
The method of claim 19, wherein: a. said step of obtaining gamma ray spectra of unknown materials comprises the step of obtaining formation gamma ray spectra for plural depths in the borehole; and b. said step of comparing comprises the step of comparing gamma ray spectra of unknown materials for each of plural depths in the borehole with the standard spectra; and c. said step of obtaining the salinity of water in the formation comprises the step of obtaining the salinity of water in the earth formations at plural depths in the borehole.
Claim 27
Dependent Claim
23 words
The method of claim 19, further including the step of: forming a record of formation water salinity as a function of borehole depth.
Claim 28
Independent Claim
160 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the volume fractions of formation constituents in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 29
Independent Claim
160 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the volume fractions of formation constituents in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 30
Dependent Claim
35 words
The method of claim 25, further including the step of: obtaining the porosity of the formation from the quantitative estimate of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 31
Dependent Claim
39 words
The method of claim 25, further including the step of: obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 32
Dependent Claim
97 words
The method of claim 25, wherein: a. said step of obtaining gamma ray spectra of unknown materials comprises the step of obtaining formation gamma ray spectra for plural depths in the borehole; and b. said step of comparing comprises the step of comparing gamma ray spectra of unknown materials for each of plural depths in the borehole with the standard spectra; and c. said step of obtaining the volume fractions of formation constituents of the formation comprises the step of obtaining the voluMe fractions of formation constituents of the earth formations at plural depths in the borehole.
Claim 33
Dependent Claim
26 words
The method of claim 25, further including the step of: forming a record of the volume fractions of formation constituents as a function of borehole depth.
Claim 34
Independent Claim
156 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the porosity of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 35
Independent Claim
156 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the porosity of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 36
Dependent Claim
39 words
The method of claim 30, further including the step of: obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 37
Dependent Claim
88 words
The method of claim 30, wherein: a. said step of obtaining gamma ray spectra of unknown materials comprises the step of obtaining formation gamma ray spectra for plural depths in the borehole; b. said step of comparing comprises the step of comparing gamma ray spectra of unknown materials for each of plural depths in the borehole with the standard spectra; and c. said step of obtaining the porosity of the formation comprises the step of obtaining the porosity of the earth formations at plural depths in the borehole.
Claim 38
Dependent Claim
21 words
The method of claim 30, further including the step of: forming a record of porosity as a function of borehole depth.
Claim 39
Independent Claim
159 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the ratios of formation constituents of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 40
Independent Claim
159 words
A method for analysis of earth formations surrounding a well borehole wherein the macroscopic thermal neutron capture cross-section of the formations is known, comprising the steps of: a. obtaining standard gamma ray energy spectra of materials postulated to be in formations surrounding a well borehole; b. bombarding the earth formations in the vicinity of the borehole with fast neutrons which are slowed down and thereafter engage in neutron capture reactions with materials in the vicinity of the borehole; c. obtaining gamma ray energy spectra of unknown materials surrounding the well borehole; d. comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and e. obtaining the ratios of formation constituents of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 41
Dependent Claim
95 words
The method of claim 34, wherein: a. said step of obtaining gamma ray spectra of unknown materials comprises the step of obtaining formation gamma ray spectra for plural depths in the borehole; and b. said step of comparing comprises the step of comparing gamma ray spectra of unknown materials for each of plural depths in the borehole with the standard spectra; and c. said step of obtaining the ratios of formation constituents of the formation comprises the step of obtaining the ratios of formation constituents of the earth formations at plural depths in the borehole.
Claim 42
Dependent Claim
21 words
The method of claim 34, further including the step of: forminG a record of ratios as a function of borehole depth.
Claim 43
Dependent Claim
120 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining quantitatively the primary formation parameters of the formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 44
Dependent Claim
120 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining quantitatively the primary formation parameters of the formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 45
Dependent Claim
119 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the water saturation of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 46
Dependent Claim
119 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the water saturation of the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 47
Dependent Claim
34 words
The machine of claim 38, further including: means for obtaining the porosity of the formation from the quantitative estimate of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 48
Dependent Claim
37 words
The machine for claim 38, further including: means for obtaining the salinity of water in the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 49
Dependent Claim
39 words
The machine for claim 38, further including: means for obtaining the volume fractions of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 50
Dependent Claim
42 words
The machine of claim 38, wherein said means for comparing comprises: means for obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 51
Dependent Claim
120 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the salinity of water in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 52
Dependent Claim
120 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the salinity of water in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 53
Dependent Claim
31 words
The machine of claim 43, further including: means for obtaining the porosity of the formation from the quantitative estimate of element composition and the known macroscopic cross-section of the earth formation.
Claim 54
Dependent Claim
39 words
The machine of claim 43, further including: means for obtaining the volume fractions of formation constituents of the earth formation from the quantitative measurE of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 55
Dependent Claim
38 words
The machine of claim 43, further including: means for obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 56
Dependent Claim
122 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the volume fractions of formation constituents in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 57
Dependent Claim
122 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the volume fractions of formation constituents in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 58
Dependent Claim
34 words
The machine of claim 47, further including: means for obtaining the porosity of the formation from the quantitative estimate of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 59
Dependent Claim
38 words
The machine of claim 47, further including: means for obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 60
Dependent Claim
118 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the porosity in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 61
Dependent Claim
118 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the porosity in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 62
Dependent Claim
38 words
The machine of claim 50, further including: means for obtaining the ratios of formation constituents of the earth formation from the quantitative measure of element composition and the known macroscopic thermal neutron capture cross-section of the earth formation.
Claim 63
Dependent Claim
121 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the ratios of formation constituents in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
Claim 64
Dependent Claim
121 words
An automated data processing machine for analyzing earth formations surrounding a well borehole based on standard gamma ray spectra of materials postulated to be in the formation, gamma ray spectra of unknown materials surrounding the well borehole and the known macroscopic thermal neutron capture cross-section of the formation, comprising: a. means for comparing an unknown gamma ray spectrum with a composite weighted mixture of the standard gamma ray spectra to obtain therefrom a quantitative measure of the percentage composition of elements in the vicinity of the borehole; and b. means for obtaining the ratios of formation constituents in the earth formation from the quantitative measure of percentage composition of elements and the known macroscopic thermal neutron capture cross-section of the formation.
References Cited (Backward Citations)
US3739171A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |