US3617867A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for well logging utilizing resonance
Assignee: Texaco Inc
•
Filing: 1953-07-17
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Granted: 1971-11-02
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Expires: 1973-07-17
Abstract
Abstract 1. In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, and detecting the resulting input of energy from the alternating magnetic field to the nuclei.
Inventors
- 👤 Gerherd Herzog
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:17
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/32
Claims Analysis
Total Claims: 113
Claim 1
Independent Claim
81 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, and detecting the resulting input of energy from the alternating magnetic field to the nuclei.
Claim 2
Dependent Claim
81 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, and detecting the resulting input of energy from the alternating magnetic field to the nuclei.
Claim 3
Dependent Claim
86 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms of a petroleum hydrocarbon, and detecting the resulting input of energy from the alternating magnetic field to the nuclei when the petroleum hydrocarbon is present in the region.
Claim 4
Dependent Claim
86 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms of a petroleum hydrocarbon, and detecting the resulting input of energy from the alternating magnetic field to the nuclei when the petroleum hydrocarbon is present in the region.
Claim 5
Dependent Claim
94 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent one portion of the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, detecting the resulting input of energy from the alternating magnetic field to the nuclei, and repeating the foregoing steps at another portion of the well.
Claim 6
Dependent Claim
94 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent one portion of the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, detecting the resulting input of energy from the alternating magnetic field to the nuclei, and repeating the foregoing steps at another portion of the well.
Claim 7
Dependent Claim
87 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the bottom of the well as drilling proceeds, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, and detecting the resulting input of energy from the alternating magnetic field to the nuclei.
Claim 8
Dependent Claim
87 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the bottom of the well as drilling proceeds, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, and detecting the resulting input of energy from the alternating magnetic field to the nuclei.
Claim 9
Dependent Claim
89 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in substance sought for in the region, and detecting the resulting input of energy from the alternating magnetic field to the nuclei when the substance is present in the region.
Claim 10
Dependent Claim
89 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in substance sought for in the region, and detecting the resulting input of energy from the alternating magnetic field to the nuclei when the substance is present in the region.
Claim 11
Dependent Claim
86 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance sought in the earth adjacent the well, and detecting the condition of nuclear resonance which results when said Substance is present in said region.
Claim 12
Dependent Claim
86 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance sought in the earth adjacent the well, and detecting the condition of nuclear resonance which results when said Substance is present in said region.
Claim 13
Dependent Claim
22 words
Process according to claim 6 in which the width of the frequency band in which the condition of resonance occurs is determined.
Claim 14
Dependent Claim
20 words
Process according to claim 6 in which the relaxation time of the nuclei from said condition of resonance is determined.
Claim 15
Dependent Claim
95 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, detecting the resulting input of energy from the alternating magnetic field to the nuclei, and measuring the frequency of the alternating magnetic field when said input of energy occurs.
Claim 16
Dependent Claim
95 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, detecting the resulting input of energy from the alternating magnetic field to the nuclei, and measuring the frequency of the alternating magnetic field when said input of energy occurs.
Claim 17
Dependent Claim
130 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region a first alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the first alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, detecting the resulting input of energy from the first alternating magnetic field to the nuclei, and modulating the DC magnetic field by superimposing upon it a second alternating magnetic field of relatively low frequency so as to sweep back and forth through the condition of nuclear resonance which occurs when frequency of the first alternating magnetic field is tuned to said nuclei
Claim 18
Dependent Claim
130 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in a region including earth adjacent the well, simultaneously producing in the same region a first alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the first alternating magnetic field being tuned to the resonance frequency for nuclei of atoms present in a substance contained in the region, detecting the resulting input of energy from the first alternating magnetic field to the nuclei, and modulating the DC magnetic field by superimposing upon it a second alternating magnetic field of relatively low frequency so as to sweep back and forth through the condition of nuclear resonance which occurs when frequency of the first alternating magnetic field is tuned to said nuclei
Claim 19
Dependent Claim
23 words
Process according to claim 10 in which the width of the frequency band at which the condition of nuclear resonance occurs is determined.
Claim 20
Dependent Claim
20 words
Process according to claim 10 in which the relaxation time for the nuclei from the condition of resonance is measured.
Claim 21
Dependent Claim
90 words
In well logging, the improvement which comprises subjecting the well at a plurality of different depths to the simultaneous actions of a unidirectional magnetic field and an oscillating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, tuning the oscillating magnetic field to the resonance frequency for the nuclei of hydrogen atoms present in a petroleum compound, and detecting at said plurality of depth the input of energy which occurs from the oscillating magnetic field to the nuclei when the latter are encountered.
Claim 22
Dependent Claim
90 words
In well logging, the improvement which comprises subjecting the well at a plurality of different depths to the simultaneous actions of a unidirectional magnetic field and an oscillating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, tuning the oscillating magnetic field to the resonance frequency for the nuclei of hydrogen atoms present in a petroleum compound, and detecting at said plurality of depth the input of energy which occurs from the oscillating magnetic field to the nuclei when the latter are encountered.
Claim 23
Dependent Claim
90 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, and detecting energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field.
Claim 24
Dependent Claim
90 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, and detecting energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field.
Claim 25
Dependent Claim
94 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, and detecting the magnitude of the energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field.
Claim 26
Dependent Claim
94 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, and detecting the magnitude of the energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field.
Claim 27
Dependent Claim
102 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth aDjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, detecting energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field, and measuring the relaxation time of the nuclei from the condition of resonance.
Claim 28
Dependent Claim
102 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth aDjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, detecting energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field, and measuring the relaxation time of the nuclei from the condition of resonance.
Claim 29
Dependent Claim
96 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, modulating the unidirectional magnetic field, and detecting energy exchange between the alternating magnetic field and substances in the earth within the modulated unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field.
Claim 30
Dependent Claim
96 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the unidirectional magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, modulating the unidirectional magnetic field, and detecting energy exchange between the alternating magnetic field and substances in the earth within the modulated unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field.
Claim 31
Dependent Claim
102 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the DC magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, and measuring the energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field, the energy exchange being measured with respect to its frequency dependence.
Claim 32
Dependent Claim
102 words
In well logging, the improvement which comprises producing a unidirectional magnetic field in the earth adjacent the well, simultaneously producing in the region in which the DC magnetic field is present an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, this component being relatively weak with respect to the unidirectional magnetic field, and measuring the energy exchange between the alternating magnetic field and substances in the earth within the unidirectional magnetic field and containing nuclei in resonance with the alternating magnetic field, the energy exchange being measured with respect to its frequency dependence.
Claim 33
Dependent Claim
111 words
In apparatus for well logging, the combination which comprises a logging head adapted to be moved along a well bore, a magnet in the head for producing a unidirectional magnetic field in material around the well bore, means disposed in the head for producing an alternating magnetic field in the region of the unidirectional magnetic field and having a component of its vector transverse to that of the unidirectional magnetic field, an adjustable radio-frequency signal generator connected to the means for producing the alternating magnetic field, and means for detecting the input of energy from the alternating magnetic field to the material under a condition of nuclear resonance for the material.
Claim 34
Dependent Claim
111 words
In apparatus for well logging, the combination which comprises a logging head adapted to be moved along a well bore, a magnet in the head for producing a unidirectional magnetic field in material around the well bore, means disposed in the head for producing an alternating magnetic field in the region of the unidirectional magnetic field and having a component of its vector transverse to that of the unidirectional magnetic field, an adjustable radio-frequency signal generator connected to the means for producing the alternating magnetic field, and means for detecting the input of energy from the alternating magnetic field to the material under a condition of nuclear resonance for the material.
Claim 35
Dependent Claim
47 words
Apparatus according to claim 19 provided with a coil disposed in the head and with its axis substantially parallel to that of the unidirectional field and means for applying a low-frequency alternating current to the coil to cause the condition of nuclear resonance to be attained periodically.
Claim 36
Dependent Claim
65 words
Apparatus according to claim 19 provided with a coil disposed in the head and with its axis substantially parallel to that of the unidirectional magnetic field, means for applying a low-frequency alternating current to the coil to cause the condition of nuclear resonance to be attained periodically, and means for measuring the width of the frequency band in which the condition of resonance is attained.
Claim 37
Dependent Claim
52 words
Apparatus according to claim 19 provided with a coil disposed in the head for modulating the unidirectional magnetic field, means for applying a low-frequency alternating current to said coil to cause the condition of nuclear resonance to be attained periodically, and means for measuring the relaxation time from the condition of resonance.
Claim 38
Dependent Claim
114 words
In apparatus for well logging, the combination which comprises a logging head adapted to be moved along a well bore, a bar magnet in the head with its axis in the direction of the bore for producing a unidirectional magnetic field in material around the bore, A coil disposed in the head for producing an alternating magnetic field in the region of the unidirectional magnetic field and having a component of its vector transverse to that of the unidirectional magnetic field, an adjustable radio-frequency signal generator connected to the coil, and means for detecting the input of energy from the alternating magnetic field to the material under conditions of nuclear resonance for the material.
Claim 39
Dependent Claim
114 words
In apparatus for well logging, the combination which comprises a logging head adapted to be moved along a well bore, a bar magnet in the head with its axis in the direction of the bore for producing a unidirectional magnetic field in material around the bore, A coil disposed in the head for producing an alternating magnetic field in the region of the unidirectional magnetic field and having a component of its vector transverse to that of the unidirectional magnetic field, an adjustable radio-frequency signal generator connected to the coil, and means for detecting the input of energy from the alternating magnetic field to the material under conditions of nuclear resonance for the material.
Claim 40
Dependent Claim
126 words
In apparatus for well logging, the combination which comprises a logging head adapted to be moved along a well bore, a permanent bar magnet disposed in the head in the direction of the well bore and having a magnetic moment sufficient to produce a unidirectional magnetic field in material adjacent the well bore, means disposed in the head for producing an alternating magnetic field in the region of the unidirectional magnetic field and having a component of its vector transverse to that of the unidirectional magnetic field, an adjustable radio-frequency signal generator connected to the means for producing the alternating magnetic field, and means for detecting the input of energy from the alternating magnetic field to the material under conditions of nuclear resonance in the material.
Claim 41
Dependent Claim
126 words
In apparatus for well logging, the combination which comprises a logging head adapted to be moved along a well bore, a permanent bar magnet disposed in the head in the direction of the well bore and having a magnetic moment sufficient to produce a unidirectional magnetic field in material adjacent the well bore, means disposed in the head for producing an alternating magnetic field in the region of the unidirectional magnetic field and having a component of its vector transverse to that of the unidirectional magnetic field, an adjustable radio-frequency signal generator connected to the means for producing the alternating magnetic field, and means for detecting the input of energy from the alternating magnetic field to the material under conditions of nuclear resonance in the material.
Claim 42
Dependent Claim
110 words
Apparatus for well logging which comprises means for producing a unidirectional magnetic field in a region including earth adjacent the well, means for simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the means for producing the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms of a predetermined type, and means including apparatus for detecting the resulting input of energy from the alternating magnetic field to the nuclei for providing a comparison of the relaxation times for the nuclei of said atoms at a plurality of locations in the well.
Claim 43
Dependent Claim
110 words
Apparatus for well logging which comprises means for producing a unidirectional magnetic field in a region including earth adjacent the well, means for simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the means for producing the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms of a predetermined type, and means including apparatus for detecting the resulting input of energy from the alternating magnetic field to the nuclei for providing a comparison of the relaxation times for the nuclei of said atoms at a plurality of locations in the well.
Claim 44
Dependent Claim
21 words
The apparatus of claim 25 wherein the alternating magnetic field is tuned to the resonance frequency for protons of hydrogen atoms.
Claim 45
Dependent Claim
82 words
Apparatus for well logging comprising means for producing a unidirectional magnetic field in a region including earth adjacent the well, means for simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, means for producing the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms of a predetermined type, and means for detecting the intensity of the nuclear resonance which results in said region.
Claim 46
Dependent Claim
82 words
Apparatus for well logging comprising means for producing a unidirectional magnetic field in a region including earth adjacent the well, means for simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, means for producing the alternating magnetic field being tuned to the resonance frequency for nuclei of atoms of a predetermined type, and means for detecting the intensity of the nuclear resonance which results in said region.
Claim 47
Dependent Claim
18 words
The apparatus of claim 27 further including means for periodically varying the strength of the unidirectional magnetic field.
Claim 48
Dependent Claim
18 words
The apparatus of claim 27 further including means for periodically varying the frequency of the alternating magnetic field.
Claim 49
Dependent Claim
31 words
The apparatus of claim 27 further including means for frequency modulating the alternating magnetic field at a modulation period which is less than the relaxation time of the nuclei being investigated.
Claim 50
Dependent Claim
149 words
Apparatus for well logging comprising means for producing a unidirectional magnetic field in a region including formations adjacent the well bore, generator means for simultaneously producing in the same region a frequency-modulated alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the carrier frequency of the generator means being tuned to the resonance frequency for nuclei of hydrogen atoms, receiving means for producing an indication of the amplitude of alternating signals, means for providing a reference alternating signal from the generator means, means for providing an alternating signal having an amplitude which varies with the intensity of the nuclear resonance which results in said region, and means for causing said alternating signals to be applied alternately to the input of the receiving means so that the receiving means provides an indication of the difference between the amplitudes of the two signals.
Claim 51
Dependent Claim
149 words
Apparatus for well logging comprising means for producing a unidirectional magnetic field in a region including formations adjacent the well bore, generator means for simultaneously producing in the same region a frequency-modulated alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the carrier frequency of the generator means being tuned to the resonance frequency for nuclei of hydrogen atoms, receiving means for producing an indication of the amplitude of alternating signals, means for providing a reference alternating signal from the generator means, means for providing an alternating signal having an amplitude which varies with the intensity of the nuclear resonance which results in said region, and means for causing said alternating signals to be applied alternately to the input of the receiving means so that the receiving means provides an indication of the difference between the amplitudes of the two signals.
Claim 52
Dependent Claim
59 words
The apparatus of claim 31 wherein the carrier frequency of the generator means is frequency-modulated through a band width which is approximately equal to the frequency of the carrier divided by the quality factor of the receiving means, and wherein the modulation period is substantially less than the relaxation time of the nuclei of the hydrogen atoms being investigated.
Claim 53
Dependent Claim
98 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including the formations adjacent the well bore, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the strength of the unidirectional magnetic field and the frequency of the alternating magnetic field being adjusted to cause nuclei of atoms of a certain type in the region to resonate at locations spaced predetermined distances from the well bore, and detecting the response of the nuclei to the magnetic fields.
Claim 54
Dependent Claim
98 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including the formations adjacent the well bore, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the strength of the unidirectional magnetic field and the frequency of the alternating magnetic field being adjusted to cause nuclei of atoms of a certain type in the region to resonate at locations spaced predetermined distances from the well bore, and detecting the response of the nuclei to the magnetic fields.
Claim 55
Dependent Claim
32 words
The method of claim 33 wherein the strength of the unidirectional magnetic field in said region is varied so that the response of the nuclei to the magnetic fields can be detected.
Claim 56
Dependent Claim
29 words
The method of claim 33 wherein the frequency of the alternating magnetic field is varied so that the response of the nuclei to the magnetic fields can be detected.
Claim 57
Dependent Claim
27 words
The method of claim 33 wherein the alternating magnetic field is frequency-modulated and the modulation period is less than the relaxation time of the nuclei being investigated.
Claim 58
Dependent Claim
103 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including formations adjacent the well bore, simultaneously producing in the same region an oscillating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the frequency of the oscillating magnetic field and the strength of the unidirectional magnetic field being proportioned to cause nuclei of hydrogen atoms in the region to resonate, varying one of the magnetic fields to vary the locations in the region at which the nuclei resonate, and detecting the response of the nuclei to the magnetic fields.
Claim 59
Dependent Claim
103 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including formations adjacent the well bore, simultaneously producing in the same region an oscillating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the frequency of the oscillating magnetic field and the strength of the unidirectional magnetic field being proportioned to cause nuclei of hydrogen atoms in the region to resonate, varying one of the magnetic fields to vary the locations in the region at which the nuclei resonate, and detecting the response of the nuclei to the magnetic fields.
Claim 60
Dependent Claim
76 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including formations adjacent the well bore, simultaneously producing in the same region a frequency-modulated radio frequency magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the radio frequency field being tuned to the resonance frequency for nuclei of hydrogen atoms, and detecting the intensity of the nuclear resonance which results in said region.
Claim 61
Dependent Claim
76 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including formations adjacent the well bore, simultaneously producing in the same region a frequency-modulated radio frequency magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the radio frequency field being tuned to the resonance frequency for nuclei of hydrogen atoms, and detecting the intensity of the nuclear resonance which results in said region.
Claim 62
Dependent Claim
45 words
The method of claim 38 further including the step of varying the amplitude of the radio frequency field to ascertain the signal strength required to saturate the formations in said region, thereby providing a measure of the relaxation time of the nuclei in the region.
Claim 63
Dependent Claim
132 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including the formations adjacent the well bore, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the strength of the unidirectional magnetic field and the frequency of the alternating magnetic field being adjusted to cause nuclei of hydrogen atoms to resonate at locations spaced predetermined distances from the well bore, detecting the intensity of the nuclear resonance which results in said region, and varying the amplitude of the alternating magnetic field to ascertain the signal strength required to saturate the formations in said region, thereby providing an indication of the relaxation times of the nuclei of hydrogen atoms in the region.
Claim 64
Dependent Claim
132 words
In well logging, the improvement which comprises producing a nonhomogeneous unidirectional magnetic field in a region including the formations adjacent the well bore, simultaneously producing in the same region an alternating magnetic field having a component of its vector transverse to that of the unidirectional magnetic field, the strength of the unidirectional magnetic field and the frequency of the alternating magnetic field being adjusted to cause nuclei of hydrogen atoms to resonate at locations spaced predetermined distances from the well bore, detecting the intensity of the nuclear resonance which results in said region, and varying the amplitude of the alternating magnetic field to ascertain the signal strength required to saturate the formations in said region, thereby providing an indication of the relaxation times of the nuclei of hydrogen atoms in the region.
Claim 65
Dependent Claim
74 words
In a method of iNvestigating wells drilled into the earth, the steps of establishing a substantially constant magnetic field in earth formation traversed by a well, simultaneously establishing in said formation at an angle to said constant field an alternating magnetic field at a frequency substantially equal to the frequency of precession of nuclei of an element embodying magnetic properties and comprising said formation, and obtaining indications of the relaxation time of said nuclei.
Claim 66
Dependent Claim
74 words
In a method of iNvestigating wells drilled into the earth, the steps of establishing a substantially constant magnetic field in earth formation traversed by a well, simultaneously establishing in said formation at an angle to said constant field an alternating magnetic field at a frequency substantially equal to the frequency of precession of nuclei of an element embodying magnetic properties and comprising said formation, and obtaining indications of the relaxation time of said nuclei.
Claim 67
Dependent Claim
104 words
A well logging apparatus comprising an elongated instrument adapted to be moved through a well bore along its principal axis including means for producing a unidirectional magnetic field having flux lines which pass through a region located along the principal axis of the instrument outside the tool, means for simultaneously producing an alternating magnetic field coincident with and having a component of its vector transverse to that of the unidirectional magnetic field, the means for producing an alternating magnetic field being tuned to the resonance frequency for nuclei of predetermined atoms, and means for detecting the response of said nuclei to the magnetic fields.
Claim 68
Dependent Claim
104 words
A well logging apparatus comprising an elongated instrument adapted to be moved through a well bore along its principal axis including means for producing a unidirectional magnetic field having flux lines which pass through a region located along the principal axis of the instrument outside the tool, means for simultaneously producing an alternating magnetic field coincident with and having a component of its vector transverse to that of the unidirectional magnetic field, the means for producing an alternating magnetic field being tuned to the resonance frequency for nuclei of predetermined atoms, and means for detecting the response of said nuclei to the magnetic fields.
Claim 69
Dependent Claim
125 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a unidirectional magnetic field, coil means mounted in one arm of an impedance bridge and disposed so as to subject said nuclei to an alternating magnetic field directed at an angle to said unidirectional field, a source of constant frequency alternating current connected to energize said bridge, means for periodically sweeping the amplitude of said unidirectional field through a range including at least one value for which Larmor precession of said nuclei will occur, and means for providing indications of energy absorbed from said alternating field.
Claim 70
Dependent Claim
125 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a unidirectional magnetic field, coil means mounted in one arm of an impedance bridge and disposed so as to subject said nuclei to an alternating magnetic field directed at an angle to said unidirectional field, a source of constant frequency alternating current connected to energize said bridge, means for periodically sweeping the amplitude of said unidirectional field through a range including at least one value for which Larmor precession of said nuclei will occur, and means for providing indications of energy absorbed from said alternating field.
Claim 71
Dependent Claim
105 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material at a selected level in a well to a polarizing magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said polarized magnetic field, varying at least one of two quantities including the amplitude of said polarizing field and the frequency of said alternating field through a range including a value for which Larmor precession of selected nuclei will be sustained, producing a signal representative of said Larmor precession of nuclei, and obtaining indications of said signal.
Claim 72
Dependent Claim
105 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material at a selected level in a well to a polarizing magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said polarized magnetic field, varying at least one of two quantities including the amplitude of said polarizing field and the frequency of said alternating field through a range including a value for which Larmor precession of selected nuclei will be sustained, producing a signal representative of said Larmor precession of nuclei, and obtaining indications of said signal.
Claim 73
Dependent Claim
37 words
A method as defined in claim 44 in which indications are obtained of an effect caused by the Larmor precession of the nuclei only during a selected portion of the range through which said quantity is varied.
Claim 74
Dependent Claim
36 words
A method as defined in claim 44 in which the range through which said one quantity is varied is greater than a line width, and indications are obtained of the energy absorbed from said alternating field.
Claim 75
Dependent Claim
37 words
A method as defined in claim 44 in which the range through which said one quantity is varied is less than a line width and dispersion-type indications are obtained of the energy absorbed from said alternating field.
Claim 76
Dependent Claim
129 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in a well to a polarizing magnetic field, second magnet means mounted in fixed relation to said first magnet means for subjecting said nuclei to an alternating magnetic field directed at an angle to said polarizing field, means for varying at least one of two quantities including the amplitude of said polarizing field and the frequency of said alternating field through a range including a value for which Larmor precession of selected nuclei will be sustained, means providing a Signal representative of said Larmor precession of nuclei, and means providing indications of said signal.
Claim 77
Dependent Claim
129 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in a well to a polarizing magnetic field, second magnet means mounted in fixed relation to said first magnet means for subjecting said nuclei to an alternating magnetic field directed at an angle to said polarizing field, means for varying at least one of two quantities including the amplitude of said polarizing field and the frequency of said alternating field through a range including a value for which Larmor precession of selected nuclei will be sustained, means providing a Signal representative of said Larmor precession of nuclei, and means providing indications of said signal.
Claim 78
Dependent Claim
40 words
Apparatus as defined in claim 48 in which said signal providing means comprises coil means disposed in inductive relation to magnetic field components normal to a plane defined by the intersecting axes of said polarizing field and said alternating field.
Claim 79
Dependent Claim
109 words
In a method of determining the magnetic resonance properties of that portion of material located at a predetermined depth beneath the surface of said material, the steps of applying a substantially constant divergent magnetic field between spaced-apart locations on said surface whereby said field decreases in intensity with the distance behind said surface, applying an alternating magnetic field perpendicularly to said constant field in said material and at a frequency equal to the resonance precession frequency of selected paramagnetic particles in a constant field of the particular intensity of said constant field at the predetermined depth of said portion, and obtaining indications of the magnetic resonance in said particles.
Claim 80
Dependent Claim
109 words
In a method of determining the magnetic resonance properties of that portion of material located at a predetermined depth beneath the surface of said material, the steps of applying a substantially constant divergent magnetic field between spaced-apart locations on said surface whereby said field decreases in intensity with the distance behind said surface, applying an alternating magnetic field perpendicularly to said constant field in said material and at a frequency equal to the resonance precession frequency of selected paramagnetic particles in a constant field of the particular intensity of said constant field at the predetermined depth of said portion, and obtaining indications of the magnetic resonance in said particles.
Claim 81
Dependent Claim
112 words
In apparatus for geophysical exploration in wells drilled into the earth, the combination of an enclosure adapted to be lowered into a well, means in said enclosure for producing a substantially constant magnetic field in a region including an earth formation in situ traversed by the well, coil means in said enclosure for producing an alternating field in said region at an angle to said constant field and at a frequency appropriate to produce gyromagnetic resonance, and electrical means cooperating with said constant magnetic field and with said coil means for obtaining indications of relaxation times of gyromagnetic precession of nuclei embodying magnetic properties and comprising molecules of material in said region.
Claim 82
Dependent Claim
112 words
In apparatus for geophysical exploration in wells drilled into the earth, the combination of an enclosure adapted to be lowered into a well, means in said enclosure for producing a substantially constant magnetic field in a region including an earth formation in situ traversed by the well, coil means in said enclosure for producing an alternating field in said region at an angle to said constant field and at a frequency appropriate to produce gyromagnetic resonance, and electrical means cooperating with said constant magnetic field and with said coil means for obtaining indications of relaxation times of gyromagnetic precession of nuclei embodying magnetic properties and comprising molecules of material in said region.
Claim 83
Dependent Claim
139 words
In apparatus for geophysical exploration in wells drilled into the earth, the combination of an enclosure adapted to be lowered into a well, means for producing a nuclear magnetic resonance condition in a region of the earth in situ adjacent the well, said means including magnetic means having opposite poles on opposite sides of said enclosure longitudinally of the axis of the well for establishing a substantially constant magnetic field in a region including an earth formation traversed by the well, coil means in said enclosure for establishing an alternating magnetic field in said region at an angle to said constant field, and electrical means cooperating with said constant magnetic field and with said coil means for obtaining indications of relaxation times of gyromagnetic resonance precession of nuclei embodying magnetic properties and comprising molecules of material in said region.
Claim 84
Dependent Claim
139 words
In apparatus for geophysical exploration in wells drilled into the earth, the combination of an enclosure adapted to be lowered into a well, means for producing a nuclear magnetic resonance condition in a region of the earth in situ adjacent the well, said means including magnetic means having opposite poles on opposite sides of said enclosure longitudinally of the axis of the well for establishing a substantially constant magnetic field in a region including an earth formation traversed by the well, coil means in said enclosure for establishing an alternating magnetic field in said region at an angle to said constant field, and electrical means cooperating with said constant magnetic field and with said coil means for obtaining indications of relaxation times of gyromagnetic resonance precession of nuclei embodying magnetic properties and comprising molecules of material in said region.
Claim 85
Dependent Claim
88 words
Apparatus for geophysical exploration in wells drilled into the earth comprising a well-logging instrument adapted to be passed through the well, said instrument including the combination of means for subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of gyromagnetic precession in certain elementary particles which may be present in said formation and means for detecting gyromagnetic precession in said formation due to said magnetic field condition, as an indication of the presence of said elementary particles.
Claim 86
Dependent Claim
88 words
Apparatus for geophysical exploration in wells drilled into the earth comprising a well-logging instrument adapted to be passed through the well, said instrument including the combination of means for subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of gyromagnetic precession in certain elementary particles which may be present in said formation and means for detecting gyromagnetic precession in said formation due to said magnetic field condition, as an indication of the presence of said elementary particles.
Claim 87
Dependent Claim
101 words
In a method of geophysical exploration in wells drilled into the earth the steps of subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of nuclear magnetic precession in certain nuclei embodying gyromagnetic properties which may be present in said formation and detecting nuclear magnetic precession in said formation due to said magnetic field condition to derive a signal which is indicative of the relaxation time for said nuclei as an indication of the presence of said nuclei, and recording a log of the signal derived from the detected precession.
Claim 88
Dependent Claim
101 words
In a method of geophysical exploration in wells drilled into the earth the steps of subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of nuclear magnetic precession in certain nuclei embodying gyromagnetic properties which may be present in said formation and detecting nuclear magnetic precession in said formation due to said magnetic field condition to derive a signal which is indicative of the relaxation time for said nuclei as an indication of the presence of said nuclei, and recording a log of the signal derived from the detected precession.
Claim 89
Dependent Claim
33 words
A method as defined in claim 54 wheRein the detected precession indicates the relaxation times for a plurality of different substances comprising material in said formation and having like nuclei embodying magnetic properties.
Claim 90
Dependent Claim
15 words
A method as defined in claim 55 wherein said different substances are oil and water.
Claim 91
Dependent Claim
83 words
In a method of geophysical exploration in wells drilled into the earth, the steps of subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of gyromagnetic precession in certain elementary particles which may be present in said formation and detecting gyromagnetic precession of elementary particles in said formation due to said magnetic field condition, as an indication of the presence of said elementary particles, and recording a log of the detected response.
Claim 92
Dependent Claim
83 words
In a method of geophysical exploration in wells drilled into the earth, the steps of subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of gyromagnetic precession in certain elementary particles which may be present in said formation and detecting gyromagnetic precession of elementary particles in said formation due to said magnetic field condition, as an indication of the presence of said elementary particles, and recording a log of the detected response.
Claim 93
Dependent Claim
120 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a substantially constant magnetic field, second magnet means mounted in fixed relation to said first magnet means for subjecting said nuclei to a second magnetic field directed at an angle to said constant magnetic field, frequency modulated oscillator means connnected to energize said second magnet means with alternating current in a range of frequencies including the Larmor precession frequency for selected nuclei, and means for detecting gyromagnetic precession produced in said material due to the fields produced by said magnet means.
Claim 94
Dependent Claim
120 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a substantially constant magnetic field, second magnet means mounted in fixed relation to said first magnet means for subjecting said nuclei to a second magnetic field directed at an angle to said constant magnetic field, frequency modulated oscillator means connnected to energize said second magnet means with alternating current in a range of frequencies including the Larmor precession frequency for selected nuclei, and means for detecting gyromagnetic precession produced in said material due to the fields produced by said magnet means.
Claim 95
Dependent Claim
34 words
Bore hole investigating apparatus as defined in claim 58 together with means for exhibiting a trace of the output of said detecting means in time relation to the frequency modulation of said oscillator means.
Claim 96
Dependent Claim
86 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material in situ at a selected level in the well to a substantially constant magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said constant field and oscillating at a frequency substantially equal to the Larmor precession frequency of said nuclei, providing a signal representative of said Larmor precession of the nuclei, and obtaining indications of said signal.
Claim 97
Dependent Claim
86 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material in situ at a selected level in the well to a substantially constant magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said constant field and oscillating at a frequency substantially equal to the Larmor precession frequency of said nuclei, providing a signal representative of said Larmor precession of the nuclei, and obtaining indications of said signal.
Claim 98
Dependent Claim
27 words
A method as defined in claim 60 in which the nuclei having magnetic properties comprise substances in the solid matter beyond the boundary wall of the borehole.
Claim 99
Dependent Claim
29 words
A method as defined in claim 60 in which indications are obtained of the energy absorption from said alternating magnetic field resulting from said Larmor precession of the nuclei.
Claim 100
Dependent Claim
82 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material at a selected level in a well to a substantially constant magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said constant field, sweeping the frequency of said alternating field through a range including the Larmor precession frequency of said nuclei, and obtaining indications of the energy absorbed from said alternating magnetic field.
Claim 101
Dependent Claim
82 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material at a selected level in a well to a substantially constant magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said constant field, sweeping the frequency of said alternating field through a range including the Larmor precession frequency of said nuclei, and obtaining indications of the energy absorbed from said alternating magnetic field.
Claim 102
Dependent Claim
91 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material at a selected level in a well to a first unidirectional magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said first field, sweeping the amplitude of said first field through a range including a value for which Larmor precession of selected nuclei will be sustained, providing a signal representative of said Larmor precession of nuclei, and obtaining indications of said signal.
Claim 103
Dependent Claim
91 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties and comprising material at a selected level in a well to a first unidirectional magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said first field, sweeping the amplitude of said first field through a range including a value for which Larmor precession of selected nuclei will be sustained, providing a signal representative of said Larmor precession of nuclei, and obtaining indications of said signal.
Claim 104
Dependent Claim
85 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties anD comprising material at different depths in a well to a substantially constant magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said constant field, sweeping the frequency of said alternating field through a range including the Larmor precession frequency of said nuclei, and obtaining indications at said different depths of the energy absorbed from said alternating magnetic field.
Claim 105
Dependent Claim
85 words
In a method for investigating a well drilled into the earth, the steps of subjecting nuclei having magnetic properties anD comprising material at different depths in a well to a substantially constant magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field directed at an angle to said constant field, sweeping the frequency of said alternating field through a range including the Larmor precession frequency of said nuclei, and obtaining indications at said different depths of the energy absorbed from said alternating magnetic field.
Claim 106
Dependent Claim
97 words
In apparatus for investigating a borehole drilled into the earth, means for producing gyromagnetic precession of elementary particles in material comprising the combination of magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a unidirectional magnetic field, means mounted in fixed relation to said first magnet means for subjecting said nuclei to electromagnetic wave energy at an angle to said unidirectional field, and means providing indications of nuclear magnetic resonance produced in said nuclei by said means for producing gyromagnetic precession.
Claim 107
Dependent Claim
97 words
In apparatus for investigating a borehole drilled into the earth, means for producing gyromagnetic precession of elementary particles in material comprising the combination of magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a unidirectional magnetic field, means mounted in fixed relation to said first magnet means for subjecting said nuclei to electromagnetic wave energy at an angle to said unidirectional field, and means providing indications of nuclear magnetic resonance produced in said nuclei by said means for producing gyromagnetic precession.
Claim 108
Dependent Claim
114 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a substantially constant magnetic field, second magnet means mounted in fixed relation to said first magnet means for subjecting said nuclei to an alternating magnetic field directed at an angle to said constant magnetic field, means for sweeping the frequency of said alternating magnetic field through a range including the Larmor precession frequency for selected nuclei, and means providing indications of the energy absorbed from said alternating field due to Larmor precession of said nuclei.
Claim 109
Dependent Claim
114 words
In apparatus for investigating a borehole drilled into the earth, the combination of first magnet means mounted for movement through the borehole and disposed so as to subject nuclei having magnetic properties and comprising material in the well to a substantially constant magnetic field, second magnet means mounted in fixed relation to said first magnet means for subjecting said nuclei to an alternating magnetic field directed at an angle to said constant magnetic field, means for sweeping the frequency of said alternating magnetic field through a range including the Larmor precession frequency for selected nuclei, and means providing indications of the energy absorbed from said alternating field due to Larmor precession of said nuclei.
Claim 110
Dependent Claim
100 words
In a method of exploring for minerals in the earth, the steps of subjecting nuclei having magnetic properties and comprising minerals in situ in the earth to a polarizing magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field at an angle to said constant magnetic field, varying one of two quantities including the amplitude of said polarizing field and the frequency of said alternating field through a range including a value for which Larmor precession of selected nuclei will be sustained, providing a signal representative of said Larmor precession of the nuclei, and obtaining indications of said signal.
Claim 111
Dependent Claim
100 words
In a method of exploring for minerals in the earth, the steps of subjecting nuclei having magnetic properties and comprising minerals in situ in the earth to a polarizing magnetic field, simultaneously subjecting said nuclei to an alternating magnetic field at an angle to said constant magnetic field, varying one of two quantities including the amplitude of said polarizing field and the frequency of said alternating field through a range including a value for which Larmor precession of selected nuclei will be sustained, providing a signal representative of said Larmor precession of the nuclei, and obtaining indications of said signal.
Claim 112
Dependent Claim
82 words
In a method of geophysical exploration in wells drilled into the earth, the steps of subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of nuclear magnetic resonance in certain nuclei which may be present in said formation, detecting said detectable condition of nuclear magnetic resonance due to said magnetic field condition, as an indication of the presence of said certain nuclei, and providing a signal indication of the detected response.
Claim 113
Dependent Claim
82 words
In a method of geophysical exploration in wells drilled into the earth, the steps of subjecting earth formations in situ adjacent the well to a magnetic field condition adapted to produce a given detectable condition of nuclear magnetic resonance in certain nuclei which may be present in said formation, detecting said detectable condition of nuclear magnetic resonance due to said magnetic field condition, as an indication of the presence of said certain nuclei, and providing a signal indication of the detected response.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |