US3843881A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detection of elements by irradiating material and measuring scattered radiation at two energy levels
Assignee: Phillips Petroleum Co
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Filing: 1973-01-11
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Granted: 1974-10-22
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Expires: 1993-01-11
Abstract
Abstract Metals and other elements are detected in a material by irradiating the material with high energy radiation. Scattered radiation from the material is measured by two pulse height analyzers set at two different energy levels in the region of Compton scattering. The ratio of the measured radiation at the two energy levels is indicative of the presence of the elements.
Inventors
- 👤 H Barton
- 👤 P Gray
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:51
CPC Classifications
G; G01; G01V; G01V5/00; G01V5/04; G01V5/08; G01V5/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
165 words
The method of detecting the presence of metals in subterranean formations comprising moving through a formation to be analyzed a source of electromagnetic radiation of an energy level greater thaN the energy level of X-rays emitted by the metals to be detected, moving a radiation detector through the formation adjacent the source but shielded therefrom so as to measure radiation emitted from the formation as a result of the formation being irradiated from the source, establishing a first signal representative of the radiation received by the detector at a first energy level in the region of Compton scattered radiation from the formation, establishing a second signal representative of the radiation received by the detector at a second energy level in the region of Compton scattered radiation from the formation, said two energy levels being approximately the two peak energy levels of scattered radiation from the formation, respectively, whereby a comparison of the two signals provides information regarding the presence of metal ore in the formation.
Claim 2
Independent Claim
165 words
The method of detecting the presence of metals in subterranean formations comprising moving through a formation to be analyzed a source of electromagnetic radiation of an energy level greater thaN the energy level of X-rays emitted by the metals to be detected, moving a radiation detector through the formation adjacent the source but shielded therefrom so as to measure radiation emitted from the formation as a result of the formation being irradiated from the source, establishing a first signal representative of the radiation received by the detector at a first energy level in the region of Compton scattered radiation from the formation, establishing a second signal representative of the radiation received by the detector at a second energy level in the region of Compton scattered radiation from the formation, said two energy levels being approximately the two peak energy levels of scattered radiation from the formation, respectively, whereby a comparison of the two signals provides information regarding the presence of metal ore in the formation.
Claim 3
Dependent Claim
32 words
The method of claim 1, further comprising dividing the first signal by the second signal to establish a third signal representative of the ratio of the first signal to the second signal.
Claim 4
Dependent Claim
26 words
The method of claim 2, further comprising recording the third signal as a function of the distance the source and detector are moved through the formation.
Claim 5
Dependent Claim
57 words
The method of claim 3, further comprising locating the source and detector at a region of the formation where the third signal is indicative of the presence of metal and measuring selectively radiation received at the detector at energy levels below the Compton scattering region to determine which metal ore or ores are present in the formation.
Claim 6
Dependent Claim
10 words
The method of claim 1 wherein the source comprises mercury-203.
Claim 7
Dependent Claim
10 words
The method of claim 1 wherein the source comprises iodine-125.
Claim 8
Dependent Claim
10 words
The method of claim 1 wherein the source is americium-241.
Claim 9
Independent Claim
132 words
The method of detecting the presence of elements in a material which comprises irradiating the material with electromagnetic radiation at an energy level greater than the energy level of X-rays emitted by the elements to be detected, detecting radiation emitted from the material as a result of the irradiation, establishing a first signal representative of the detected radiation at a first energy level in the region of Compton scattered radiation from the material, establishing a second signal representative of the detected radiation at a second energy level in the region of Compton scattered radiation from the material, said two energy levels being approximately the two peak energy levels of scattered radiation from the material, respectively, and establishing a third signal representative of the ratio of the first signal to the second signal.
Claim 10
Independent Claim
132 words
The method of detecting the presence of elements in a material which comprises irradiating the material with electromagnetic radiation at an energy level greater than the energy level of X-rays emitted by the elements to be detected, detecting radiation emitted from the material as a result of the irradiation, establishing a first signal representative of the detected radiation at a first energy level in the region of Compton scattered radiation from the material, establishing a second signal representative of the detected radiation at a second energy level in the region of Compton scattered radiation from the material, said two energy levels being approximately the two peak energy levels of scattered radiation from the material, respectively, and establishing a third signal representative of the ratio of the first signal to the second signal.
Claim 11
Dependent Claim
16 words
The method of claim 8, further comprising recording a signal representative of the total radiation detected.
References Cited (Backward Citations)
US3453433A
Cited
US3521064A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-21 | 1978-04-22 | 1978-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-21 | 1982-04-22 | 1982-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-21 | 1986-04-22 | 1986-10-22 | $7700.00 | Window Closed / Lapsed |