US3784828A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Determining the location of vertical channels in a wellbore
Assignee: Schlumberger Technology Corp
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Filing: 1971-03-25
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Granted: 1974-01-08
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Expires: 1991-03-25
Abstract
Abstract An illustrative embodiment of the invention shows a radioactive tracer technique for distinguishing vertically flowing liquids in formation fractures from flows through passageways in the cement annulus between the steel casing and the borehole wall. Typically, two radiation detectors of different sensitivities respond to a radioactive tracer that has been discharged into the formation at the well depth of interest. If the tracer material moves in a vertical direction with respect to the injection depth, relatively high count rates from both of the detectors indicate that the tracer is flowing vertically through a fracture in the cement. A relatively low count rate in the less sensitive detector, however, indicates that the vertical flow is taking place away from the casing and at some depth within the formation.
Inventors
- 👤 D Hayes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:34
CPC Classifications
G; G01; G01V; G01V5/00; G01V5/04; G01V5/08
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
179 words
A method of logging cased well bores for determining whether vertical fluid communication paths exterior of the well bore casing are lying either between said well casing and adjacent earth formations or within said earth formations and comprising the steps of: displacing radioactive material laterally through the well casing adjacent an interval which may contain a vertical fluid communication path located at an unknown lateral distance from the axis of said well bore; measuring radioactive radiation along said interval for obtaining at least one radiation measurement indicative of the presence of said radioactive material in either a vertical fluid communication path between said well casing and said earth formations or in a vertical fluid communication path within said earth formation; measuring radioactive radiation energy along said interval for obtaining at least another radiation measurement selectively indicative of the presence of said radioactive material in a vertical fluid communication path between said well casing and said earth formations; and comparing said radiation measurements for determining the position of said vertical fluid communication path in relation to said well bore axis.
Claim 2
Independent Claim
179 words
A method of logging cased well bores for determining whether vertical fluid communication paths exterior of the well bore casing are lying either between said well casing and adjacent earth formations or within said earth formations and comprising the steps of: displacing radioactive material laterally through the well casing adjacent an interval which may contain a vertical fluid communication path located at an unknown lateral distance from the axis of said well bore; measuring radioactive radiation along said interval for obtaining at least one radiation measurement indicative of the presence of said radioactive material in either a vertical fluid communication path between said well casing and said earth formations or in a vertical fluid communication path within said earth formation; measuring radioactive radiation energy along said interval for obtaining at least another radiation measurement selectively indicative of the presence of said radioactive material in a vertical fluid communication path between said well casing and said earth formations; and comparing said radiation measurements for determining the position of said vertical fluid communication path in relation to said well bore axis.
Claim 3
Dependent Claim
41 words
The method of claim 1 further including the step of measuring, before said displacing step, radioactive radiation along said interval for determining the portions of said one radiation measurement and said another radiation measurement respectively resulting from natural background radioactive radiation.
Claim 4
Dependent Claim
36 words
The method of claim 1 further including: successively repeating said measuring steps for determining the lateral position of said vertical fluid communication path in relation to said well bore axis at different depths along said interval.
Claim 5
Independent Claim
184 words
A method of logging cased well bores for determining whether vertical fluid communication paths exterior of the well bore casing are lying either between said well casing and adjacent earth formations or within said earth formations and comprising the steps of: displacing radioactive material laterally through the well casing adjacent an interval which may contain a vertical fluid communication path located at an unknown lateral distance from the axis oF said well bore; measuring the high and low radioactive radiation along said interval for obtaining at least one radiation measurement indicative of the presence of said radioactive material in either a vertical fluid communication path between said well casing and said earth formations or in a vertical fluid communication path within said earth formations; measuring the high radioactive radiation along said interval for obtaining at least another radiation measurement selectively indicative of the presence of said radioactive material in a vertical fluid communication path between said well casing and said earth formations; and comparing said radiation measurements for determining the position of said vertical fluid communication path in relation to said well bore axis.
Claim 6
Independent Claim
184 words
A method of logging cased well bores for determining whether vertical fluid communication paths exterior of the well bore casing are lying either between said well casing and adjacent earth formations or within said earth formations and comprising the steps of: displacing radioactive material laterally through the well casing adjacent an interval which may contain a vertical fluid communication path located at an unknown lateral distance from the axis oF said well bore; measuring the high and low radioactive radiation along said interval for obtaining at least one radiation measurement indicative of the presence of said radioactive material in either a vertical fluid communication path between said well casing and said earth formations or in a vertical fluid communication path within said earth formations; measuring the high radioactive radiation along said interval for obtaining at least another radiation measurement selectively indicative of the presence of said radioactive material in a vertical fluid communication path between said well casing and said earth formations; and comparing said radiation measurements for determining the position of said vertical fluid communication path in relation to said well bore axis.
Claim 7
Dependent Claim
40 words
The method of claim 4 further including the step of measuring, before said displacing step, radioactive radiations along said interval for determining the portions of said one radiation measurement and said other measurement respectively resulting from natural background radioactive radiation.
Claim 8
Dependent Claim
36 words
The method of claim 4 further including: successively repeating said measuring steps for determining the lateral position of said vertical fluid communication path in relation to said well bore axis at different depths along said interval.
Claim 9
Independent Claim
201 words
A method of logging cased well bores for determining whether vertical fluid communication paths exterior of the well bore casing are lying either between said well casing and adjacent earth formations or within said earth formations and comprising the steps of: displacing radioactive material laterally through the well casing adjacent an interval which may contain a vertical fluid communication path located at an unknown lateral distance from the axis of said well bore; measuring the radioactive radiation along said interval for obtaining at least one radiation measurement indicative of the presence of said radioactive material in said vertical fluid communication path; discriminating between the high radioactive radiation and the low radioactive radiation of said measured radioactive radiation for obtaining at least one low radioactive radiation measurement indicative of the presence of said radioactive material in a vertical fluid communication path within said earth formation, and for obtaining at least one high radioactive radiation measurement indicative of the presence of said radioactive material in a vertical fluid communication path between said well casing and said earth formation; and comparing said high and low radioactive radiation measurements for determining the position of said vertical communication path in relation to said well bore axis.
Claim 10
Independent Claim
201 words
A method of logging cased well bores for determining whether vertical fluid communication paths exterior of the well bore casing are lying either between said well casing and adjacent earth formations or within said earth formations and comprising the steps of: displacing radioactive material laterally through the well casing adjacent an interval which may contain a vertical fluid communication path located at an unknown lateral distance from the axis of said well bore; measuring the radioactive radiation along said interval for obtaining at least one radiation measurement indicative of the presence of said radioactive material in said vertical fluid communication path; discriminating between the high radioactive radiation and the low radioactive radiation of said measured radioactive radiation for obtaining at least one low radioactive radiation measurement indicative of the presence of said radioactive material in a vertical fluid communication path within said earth formation, and for obtaining at least one high radioactive radiation measurement indicative of the presence of said radioactive material in a vertical fluid communication path between said well casing and said earth formation; and comparing said high and low radioactive radiation measurements for determining the position of said vertical communication path in relation to said well bore axis.
Claim 11
Dependent Claim
41 words
The method of claim 7 further including the step of measuring, before said displacing step, radioactive radiation along said interval for determining the portions of said high radiation measurement and said low radiation measurement respectively resulting from natural background radioactive radiation.
Claim 12
Dependent Claim
38 words
The method of claim 7 further including: successively repeating said measuring and discriminating steps for determining the lateral position of said vertical fluid communication path in relation to said well bore axis at different depths along said interval.
References Cited (Backward Citations)
US3251993A
Cited
US3406284A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |