US3921732A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detecting geopressured subterranean formations during drilling of a well
Assignee: ConocoPhillips Co
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Filing: 1974-06-03
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Granted: 1975-11-25
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Expires: 1994-06-03
Abstract
Abstract A method of determining lithology changes in a well during drilling operations. Abnormal formation pressure, generally geopressure, and hydrocarbon-containing environments in subterranean rock strata can be detected before drilling into the same by making aqueous slurries of samples of the formation being drilled and observing and comparing the color characteristics of the liquid recovered from the filtration of such slurries.
Inventors
- 👤 Edward B Reynolds
- 👤 Donald M Pert
- 👤 Aldo M Zanier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:10
CPC Classifications
E; E21; E21B; E21B49/00; E21B49/005
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
87 words
A method for detecting changes in properties and characteristics of a subterranean formation during drilling operations comprising: a. drilling a well in a subterranean formation utilizing a circulating drilling fluid; b. periodically collecting formation samples from increasing depths; c. preparing filtrates of aqueous slurries of said formation samples; d. determining a color characteristic of said filtrates prepared from aqueous slurries of said formation samples taken from increasing depths; and e. when said color characteristic of said filtrates begins to change rapidly with depth, instituting controlled drilling procedures.
Claim 2
Independent Claim
87 words
A method for detecting changes in properties and characteristics of a subterranean formation during drilling operations comprising: a. drilling a well in a subterranean formation utilizing a circulating drilling fluid; b. periodically collecting formation samples from increasing depths; c. preparing filtrates of aqueous slurries of said formation samples; d. determining a color characteristic of said filtrates prepared from aqueous slurries of said formation samples taken from increasing depths; and e. when said color characteristic of said filtrates begins to change rapidly with depth, instituting controlled drilling procedures.
Claim 3
Dependent Claim
24 words
The method of claim 1 where the change in formation properties and characteristics is the change from a nonhydrocarbon-containing formation to a hydrocarbon-containing formation.
Claim 4
Dependent Claim
20 words
The method of claim 1 wherein the determination of a color characteristic is carried out visually using a color chart.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein the sample of the formation is made up of cuttings.
Claim 6
Dependent Claim
24 words
The method of claim 1 wherein the change in formation properties and characteristics is a change from a normally-pressured formation to an abnormally-pressured formation.
Claim 7
Dependent Claim
13 words
The method of claim 5 wherein the abnormally-pressured formation is a geopressured formation.
References Cited (Backward Citations)
US2214674A
Cited
US2883856A
Cited
US3373440A
Cited
US3409092A
Cited
US3628131A
Cited
US3722606A
Cited
US3766993A
Cited
US3766994A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |