US3590228A
Expired / Lapsed
US
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Methods and apparatus for processing well logging data
Assignee: Schlumberger Technology Corp
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Filing: 1967-10-02
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Granted: 1971-06-29
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Expires: 1987-10-02
Abstract
Abstract The particular embodiments described herein as illustrative of the invention describe a technique for processing well-logging measurements to provide more meaningful information as to earth formation conditions. In this regard, measurements of sonic travel time, bulk density, and neutron derived porosity of the earth formations are combined to provide certain lithology indices. These lithology indices are then utilized to identify the major lithological constituents of any given formation. Once the major lithological constituents are identified, the percentages of the lithological constituents and porosity of a formation can be accurately calculated.
Inventors
- 👤 Jack A Burke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:31
CPC Classifications
G; G01; G01V; G01V11/00; G01V11/002
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
85 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of the sonic travel time, bulk density, and hydrogen content of an adjoining formation; b. computing with a machine certain lithology indices from said derived measurements, said indices being indicative of which constituents are present in a formation; and c. recording said lithology indices as a function of borehole depth for subsequent use in interpreting the derived measurements.
Claim 2
Independent Claim
85 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of the sonic travel time, bulk density, and hydrogen content of an adjoining formation; b. computing with a machine certain lithology indices from said derived measurements, said indices being indicative of which constituents are present in a formation; and c. recording said lithology indices as a function of borehole depth for subsequent use in interpreting the derived measurements.
Claim 3
Dependent Claim
73 words
The method of claim 1 wherein said lithology indices are where Delta tF is the sonic travel time of the interstitial fluid, Delta t is the measured sonic travel time of the formation, Rho B is the measured bulk density of the formation, Rho F is the interstitial fluid density, HF is the hydrogen index of the formation interstitial fluid, and phi N is the measured porosity derived from the hydrogen content measurement.
Claim 4
Dependent Claim
36 words
means responsive to the generated signals for a plurality of depth levels for indicating which one of the sets of lithological constituents defines the greatest number of computed M,N sets to identify the major lithological constituents.
Claim 5
Dependent Claim
36 words
means responsive to the generated signals for a plurality of depth levels for indicating which one of the sets of lithological constituents defines the greatest number of computed M,N sets to identify the major lithological constituents.
Claim 6
Dependent Claim
20 words
counting the computed sets of lithology indices defined by each set of lithological constituents over a given depth interval; and
Claim 7
Dependent Claim
20 words
counting the computed sets of lithology indices defined by each set of lithological constituents over a given depth interval; and
Claim 8
Dependent Claim
50 words
comparing the number of computed lithology indices sets M,N for each of the plurality of sets of lithological constituents to determine which set of lithological constituents defines the greatest number of computed lithology indices sets M,N over said given depth interval to identify the major lithological constituents of the formation.
Claim 9
Dependent Claim
50 words
comparing the number of computed lithology indices sets M,N for each of the plurality of sets of lithological constituents to determine which set of lithological constituents defines the greatest number of computed lithology indices sets M,N over said given depth interval to identify the major lithological constituents of the formation.
Claim 10
Independent Claim
90 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of the sonic travel time, bulk density and hydrogen content of an adjoining formation; b. computing with a machine certain lithology indices from said derived measurements, said indices being representative of which constituents are present in a formation; and c. using said computed lithology indices to identify at least a portion of the lithological constituents that are present in any given investigated formation.
Claim 11
Independent Claim
90 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of the sonic travel time, bulk density and hydrogen content of an adjoining formation; b. computing with a machine certain lithology indices from said derived measurements, said indices being representative of which constituents are present in a formation; and c. using said computed lithology indices to identify at least a portion of the lithological constituents that are present in any given investigated formation.
Claim 12
Dependent Claim
72 words
The method of claim 3 wherein said lithology indices are: where Delta tF is the sonic travel time of the interstitial fluid, Delta t is the measured sonic travel time of the formation, Rho B is the measured bulk density of the formation, Rho F is the interstitial fluid density, HF is the hydrogen index of the formation interstitial fluid, and phi N is the measured porosity from the measured hydrogen content.
Claim 13
Dependent Claim
59 words
The method of claim 4 wherein each lithological constituent has a unique set of lithology indices and the step of using said lithology indices to identify the lithological constituents comprises comparing the numerical relationship between the computed lithology indices and the unique lithology indices for the various lithological constituents to identify the major lithological logical constituents in the formation.
Claim 14
Dependent Claim
26 words
The method of claim 5 and further including the step of computing the percentage of bulk volume contributed by the identified major lithological constituents and porosity.
Claim 15
Dependent Claim
70 words
The method of claim 4 wherein each lithological constituent has a unique set of lithology indices, the lithology indices are computed over a given depth interval, and the step of using said lithology indices to identify the lithological constituents comprises comparing the numerical relationship between the lithology indices for the various lithological constituents and a plurality of the computed lithology indices to identify the major lithological constituents of the formation.
Claim 16
Dependent Claim
25 words
The method of claim 7 wherein the step of comParing the relationship between lithology indices to identify the major lithological constituents comprises the steps of:
Claim 17
Dependent Claim
26 words
The method claim 8 and further including the step of computing the bulk volume of the formation contributed by the identified major lithological constituents and porosity.
Claim 18
Dependent Claim
78 words
The method of claim 9 and further including the steps of: a. deriving measurements of the electrical resistivity of first and second radial portions of the formation; b. converting the first and second resistivity measurements into measurements indicating the amount of conductive fluid in the respective formation portions; and c. comparing the computed porosity and the converted resistivity measurements to obtain indications of the amounts of the different types of fluids that may be present in the formation.
Claim 19
Dependent Claim
78 words
Apparatus for processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. means for deriving a plurality of measurements representative of the acoustic travel time, bulk density, and hydrogen content of an adjoining formation; b. means for computing certain lithology indices from said derived measurements, said indices being indicative of which constituents are present in a formation; and c. means for recording said lithology indices as a function of borehole depth.
Claim 20
Dependent Claim
78 words
Apparatus for processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. means for deriving a plurality of measurements representative of the acoustic travel time, bulk density, and hydrogen content of an adjoining formation; b. means for computing certain lithology indices from said derived measurements, said indices being indicative of which constituents are present in a formation; and c. means for recording said lithology indices as a function of borehole depth.
Claim 21
Dependent Claim
87 words
The apparatus of claim 11 wherein said plurality of derived measurements are combined by said computing means to produce said lithology indices M and N in accordance with the expressions: where Delta tF is the sonic travel time of the interstitial fluid, Rho F is the interstitial fluid density, HF is the hydrogen index of the formation interstitial fluid, Delta t is the measured sonic travel time, Rho B is the measured bulk density, and phi N is a measurement of porosity from the hydrogen content measurement.
Claim 22
Dependent Claim
78 words
Apparatus for processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. means for deriving a plurality of measurements representative of the sonic travel time, bulk density, and hydrogen content of an adjoining formation; b. means for computing certain lithology indices from said derived measurements, said indices being indicative of which constituents are present in a formation; and c. means responsive to said lithology indices for identifying the major lithological constituents.
Claim 23
Dependent Claim
78 words
Apparatus for processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. means for deriving a plurality of measurements representative of the sonic travel time, bulk density, and hydrogen content of an adjoining formation; b. means for computing certain lithology indices from said derived measurements, said indices being indicative of which constituents are present in a formation; and c. means responsive to said lithology indices for identifying the major lithological constituents.
Claim 24
Dependent Claim
88 words
The apparatus of claim 13 wherein said plurality of derived measurements are combined by said computing means to compute said lithology indices M and N in accordance with the expressions: where Delta tF is the sonic travel time of the interstitial fluid, Rho F is the interstitial fluid density, HF is the hydrogen index of the formation interstitial fluid, Delta t is the measured sonic travel time, Rho B is the measured bulk density, and phi N is a measurement of porosity derived from the measured hydrogen content.
Claim 25
Dependent Claim
52 words
The apparatus of claim 14 wherein each lithological constituent has a unique set of lithology indices and the means for identifying the major lithological constituents includes means for comparing the computed lithology indices with the unique lithology indices for the lithological constituents and generating a signal indicative of the major lithological constituents.
Claim 26
Dependent Claim
59 words
The apparatus of claim 15 and further including means responsive to the generated signal indicative of the major lithological constituents and the measurements representative of sonic travel time Delta t, neutron derived porosity phi N, and bulk density Rho B for generating signals representative of the percentages of bulk volume contributed by the identified major lithological constituents and porosity.
Claim 27
Dependent Claim
26 words
The apparatus of claim 14 wherein each lithological constituent has a unique set of lithology indices and the means for identifying the major lithological constituents includes:
Claim 28
Independent Claim
107 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of the sonic travel time, bulk density and hydrogen content of an adjoining formation; b. generating signals representative of the sonic travel time, density, and hydrogen index of the interstitial fluid; c. combining with a machine said derived measurements and generated signals in a certain relationship to produce at least one lithology indicia representative of which lithological constituents are present in a formation; d. recording said lithology indicia as a function of the depth at which said measurements were derived.
Claim 29
Independent Claim
107 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of the sonic travel time, bulk density and hydrogen content of an adjoining formation; b. generating signals representative of the sonic travel time, density, and hydrogen index of the interstitial fluid; c. combining with a machine said derived measurements and generated signals in a certain relationship to produce at least one lithology indicia representative of which lithological constituents are present in a formation; d. recording said lithology indicia as a function of the depth at which said measurements were derived.
Claim 30
Independent Claim
107 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of a plurality of characteristics of an adjoining formation; b. computing with a machine lithology indices from said derived measurements, said indices being representative of which constituents are present in a formation; and c. comparing with a machine the relationship of said computed lithology indices to the unique lithology indices for the lithological constituents of a plurality of sets of such lithological constituents and generating a signal representative of which set of lithological constituents best defines said computed lithology indices.
Claim 31
Independent Claim
107 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of a plurality of characteristics of an adjoining formation; b. computing with a machine lithology indices from said derived measurements, said indices being representative of which constituents are present in a formation; and c. comparing with a machine the relationship of said computed lithology indices to the unique lithology indices for the lithological constituents of a plurality of sets of such lithological constituents and generating a signal representative of which set of lithological constituents best defines said computed lithology indices.
Claim 32
Dependent Claim
62 words
The method of claim 19 and further including the steps of repeating the steps of deriving, computing, and comparing for a plurality of depth levels in a borehole, counting the number of computed lithology indices which are defined by each set of lithological constituents, and producing a signal representative of which set of constituents defines the greatest number of computed lithology indices.
Claim 33
Independent Claim
110 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of a plurality of characteristics of an adjoining formation; b. computing with a machine lithology indices from said derived measurements, said indices being representative of which constituents are present in a formation; and c. generating an output signal indicative of whether the computed indices arE within certain limits defined by unique lithology indices for a set of lithological constituents whereby the presence of said set of lithological constituents in a formation will be indicated if said computed indices are within said certain limits.
Claim 34
Independent Claim
110 words
A method of machine processing well-logging data derived from apparatus lowered in a borehole for investigating subsurface earth formations, comprising: a. deriving a plurality of measurements representative of a plurality of characteristics of an adjoining formation; b. computing with a machine lithology indices from said derived measurements, said indices being representative of which constituents are present in a formation; and c. generating an output signal indicative of whether the computed indices arE within certain limits defined by unique lithology indices for a set of lithological constituents whereby the presence of said set of lithological constituents in a formation will be indicated if said computed indices are within said certain limits.
Claim 35
Dependent Claim
84 words
The method of claim 21 wherein the step of generating an output signal includes using said computed lithology indices to determine if said computed indices are within limits defined by mathematical expressions giving the connections between the sets of unique indices for each lithological constituent of said set of constituents, and generating said output signal in a state to indicate that the formation under investigation is made up of at least said set of lithological constituents if said computed indices are within said limits.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |