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Patent US2749503A successfully refreshed from Google Patents.
US2749503A
Expired / Lapsed
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Electrical logging in non-conductive drilling liquids
Assignee: Schlumberger Well Surveying Corp
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Filing: 1951-11-28
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Granted: 1956-06-05
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Expires: 1971-11-28
Abstract
No abstract record available.
Inventors
- 👤 Doll Henri-Georges
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:27
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/20; G01V3/24
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
87 words
A METHOD OF LOGGING A BOREHOLE CONTAINING SUBSTANTIALLY NON-CONDUCTIVE LIQUID IN WHICH FINELY DIVIDED SOLIDS ARE SUSPENDED, THE FILTRATE FROM SAID LIQUID TENDING TO INVADE PERMEABLE FORMATIONS TRAVERSED BY THE BOREHOLE AND LEAVE A HIGHLY RESISTIVE MUD CAKE ON THE WALL THEREOF, COMPRISING THE STEPS OF SLIDING AN ELECTRODE ALONG THE WALL OF THE BOREBOLE IN ENGAGEMENT THEREWITH AND OVER ANY MUD CAKE THAT MAY BE PRESENT, AND DETECTING THE MUD CAKE IN TERMS OF THE CAPACITIVE REACTANCE BETWEEN THE ELECTRODE AND THE FORMATION BEHIND THE SAME.
Claim 2
Independent Claim
87 words
A METHOD OF LOGGING A BOREHOLE CONTAINING SUBSTANTIALLY NON-CONDUCTIVE LIQUID IN WHICH FINELY DIVIDED SOLIDS ARE SUSPENDED, THE FILTRATE FROM SAID LIQUID TENDING TO INVADE PERMEABLE FORMATIONS TRAVERSED BY THE BOREHOLE AND LEAVE A HIGHLY RESISTIVE MUD CAKE ON THE WALL THEREOF, COMPRISING THE STEPS OF SLIDING AN ELECTRODE ALONG THE WALL OF THE BOREBOLE IN ENGAGEMENT THEREWITH AND OVER ANY MUD CAKE THAT MAY BE PRESENT, AND DETECTING THE MUD CAKE IN TERMS OF THE CAPACITIVE REACTANCE BETWEEN THE ELECTRODE AND THE FORMATION BEHIND THE SAME.
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) | 1959-06-05 | 1959-12-05 | 1960-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-06-05 | 1963-12-05 | 1964-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-06-05 | 1967-12-05 | 1968-06-05 | $7700.00 | Window Closed / Lapsed |