US3864969A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Station measurements of earth formation thermal conductivity
Assignee: Texaco Inc
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Filing: 1973-08-06
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Granted: 1975-02-11
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Expires: 1993-08-06
Abstract
Abstract An illustrative embodiment of the invention provides two methods for making station measurements of earth formation thermal conductivity. In one method the formation is heated for a predetermined length of time to elevate its temperature. The rate of decay of temperature back to ambient is then measured and used to derive an indication of the thermal conductivity. In the second method the formation is heated by a constant output heat source and its rate of temperature increase is measured and used to derive an indication of the thermal conductivity. These measurements may be used to distinguish hydrocarbon bearing formations from water bearing formations.
Inventors
- 👤 Jr Harry D Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:22
CPC Classifications
G; G01; G01N; G01N25/00; G01N25/18; E; E21; E21B; E21B47/00; E21B47/06; E21B47/07; G01V; G01V9/00; G01V9/005
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
208 words
A method for thermally logging a well borehole to obtain indications of a quantity functionally related to the thermal conductivity of earth formations in the vicinity of the borehole, comprising the steps of: positioning a well logging sonde having a source of thermal energy and a longitudinally spaced therefrom temperature sensitivE transducer in position adjacent a formation whose thermal properties are to be obtained so that said source of thermal energy defines the position of a measurement station; activating said source of thermal energy for a predetermined length of time to impart a quantity of thermal energy into said formation sufficient to increase the temperature thereof at said measurement station to a value elevated above that of its ambient borehole condition; deactivating said source of thermal energy and moving said well logging sonde to position said temperature sensitive transducer at said measurement station; measuring the temperature of the earth formations at said measurement station at two points in time separated by an amount sufficient to allow a decrease in temperature of said earth formations; and combining said two time spaced temperature measurements according to a predetermined relationship to derive an indication of a quantity functionally related to the thermal conductivity of the earth formations at said measurement station.
Claim 2
Independent Claim
208 words
A method for thermally logging a well borehole to obtain indications of a quantity functionally related to the thermal conductivity of earth formations in the vicinity of the borehole, comprising the steps of: positioning a well logging sonde having a source of thermal energy and a longitudinally spaced therefrom temperature sensitivE transducer in position adjacent a formation whose thermal properties are to be obtained so that said source of thermal energy defines the position of a measurement station; activating said source of thermal energy for a predetermined length of time to impart a quantity of thermal energy into said formation sufficient to increase the temperature thereof at said measurement station to a value elevated above that of its ambient borehole condition; deactivating said source of thermal energy and moving said well logging sonde to position said temperature sensitive transducer at said measurement station; measuring the temperature of the earth formations at said measurement station at two points in time separated by an amount sufficient to allow a decrease in temperature of said earth formations; and combining said two time spaced temperature measurements according to a predetermined relationship to derive an indication of a quantity functionally related to the thermal conductivity of the earth formations at said measurement station.
Claim 3
Dependent Claim
66 words
The method of claim 1 wherein said combining step is performed according to the relationship Delta T N . K/C2 where Delta T is the temperature decrease measured at said two separated time points, K is the earth formation thermal conductivity, C is the specific heat of the formation, and N is a predetermined calibration constant characteristic of the well logging sonde and the borehole geometry.
Claim 4
Dependent Claim
83 words
The method of claim 1 wherein said source of thermal energy is located longitudinally spaced above said temperature sensitive transducer and said sonde is moved upwardly in the borehole subsequent to the step of activating said source of thermal energy and all of the steps of the measurements are repeated at a plurality of selected borehole depth levels and the results recorded to provide a log of station measurements of said quantity functionally related to thermal conductivity as a function of borehole depth.
References Cited (Backward Citations)
US3807227A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-10 | 1978-08-12 | 1979-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-10 | 1982-08-12 | 1983-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-10 | 1986-08-12 | 1987-02-11 | $7700.00 | Window Closed / Lapsed |