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US2728047A
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Methods and apparatus for logging spontaneous potentials in wells
Assignee: Schlumberger Well Surveying Corp
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Filing: 1952-06-13
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Granted: 1955-12-20
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Expires: 1972-06-13
Abstract
No abstract record available.
Inventors
- 👤 Doll Henri-Georges
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:09
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/20; G01V3/24
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB597026A
Cited
US2442383A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-12-19 | 1959-06-20 | 1959-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-12-19 | 1963-06-20 | 1963-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-12-19 | 1967-06-20 | 1967-12-20 | $7700.00 | Window Closed / Lapsed |