CA1040261A
Expired / Lapsed
CA
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Method and apparatus for investigating earth formations
Assignee: Schlumberger Canada Ltd
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Filing: 1974-08-16
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Granted: 1978-10-10
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Expires: 1994-08-16
Abstract
Abstract METHOD AND APPARATUS FOR INVESTIGATING EARTH FORMATIONS ABSTRACT OF THE DISCLOSURE A method and apparatus for determining the dielectric constant of earth formations surrounding a borehole. Elec-tromagnetic energy is injected into the surrounding forma-tions and received at two locations positioned in spaced relation in the borehole. The phase difference between and attenuation of the signals received at the locations are measured. Finally, the dielectric constant associated with formations surrounding the area between the spaced locations is determined by combining the phase measurement with the attenuation measurement.
Inventors
- 👤 Andre Levy
- 👤 Pierre Grimaldi
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-10-29 11:49
CPC Classifications
—
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
102 words
Apparatus for investigating earth formations surrounding a borehole, comprising: (a) means positionable in a borehole for injecting electromagnetic energy into the surrounding formations; (b) first and second receiving means positioned in spaced relation in the borehole; (c) means for measuring the phase difference between signals received at said first and second receiving means; (d) means for measuring the relative attenuation as between signals received at said first and second receiving means; and (e) means for computing the dielectric constant associated with the formations surrounding the area between the first and second receiving locations by combining the phase measurement with the attenuation measurement.
Claim 2
Dependent Claim
102 words
Apparatus for investigating earth formations surrounding a borehole, comprising: (a) means positionable in a borehole for injecting electromagnetic energy into the surrounding formations; (b) first and second receiving means positioned in spaced relation in the borehole; (c) means for measuring the phase difference between signals received at said first and second receiving means; (d) means for measuring the relative attenuation as between signals received at said first and second receiving means; and (e) means for computing the dielectric constant associated with the formations surrounding the area between the first and second receiving locations by combining the phase measurement with the attenuation measurement.
Claim 3
Dependent Claim
66 words
Apparatus as defined by claim 1 wherein the dielectric constant, .epsilon., of the formations of interest is computed in accordance with the relationship . where .beta. and .alpha. are, respectively, phase and attenuation con-stants determined by the phase difference measuring means and the attenuation measuring means, .omega. is the angular frequency of the injected electromagnetic energy, and µ is the magnetic permeability of the surrounding formations.
Claim 4
Dependent Claim
72 words
Apparatus as defined by claim 1 wherein said computing means comprises: (f) means for deriving the quantity, .beta.2, where .beta. is a phase constant determined by the phase difference measuring means; (g) means for deriving the quantity .alpha.2, where .alpha. is an attenuation constant determined by the attenuation measuring means; and (h) means for deriving the quantity .beta.2 - .alpha.2 which is proportional to the dielectric constant of the formations of interest.
Claim 5
Independent Claim
87 words
A method of determining the dielectric constant of formations surrounding the borehole, comprising the steps of: (a) injecting electromagnetic energy into the surrounding formations; (b) receiving energy signals at first and second receiving locations; (c) measuring the phase difference between the signals received at said first and second receiving locations; (d) measuring the relative attenuation as between signals received at said first and second receiving locations; and (e) computing the dielectric constant associated with the formations of interest by combining the phase measurement with the attenuation measurement.
Claim 6
Independent Claim
87 words
A method of determining the dielectric constant of formations surrounding the borehole, comprising the steps of: (a) injecting electromagnetic energy into the surrounding formations; (b) receiving energy signals at first and second receiving locations; (c) measuring the phase difference between the signals received at said first and second receiving locations; (d) measuring the relative attenuation as between signals received at said first and second receiving locations; and (e) computing the dielectric constant associated with the formations of interest by combining the phase measurement with the attenuation measurement.
Claim 7
Dependent Claim
69 words
The method as defined by claim 4 wherein the step of computing the dielectric constant includes the steps of: (f) deriving the quantity .beta.2, where .beta. is a phase constant determined from step (c); (g) deriving the quantity .alpha.2, where .alpha. is an attenuation constant determined from step (d); and (h) deriving the quantity .beta.2 - .alpha.2 which is pro-portional to the dielectric constant of the formations of interest.
Claim 8
Dependent Claim
106 words
Apparatus for investigating earth formations surrounding a borehole, comprising: (a) means positionable in a borehole for injecting electromagnetic energy into the surrounding formations; (b) first and second receiving means positioned in spaced relation in the borehole; (c) means for measuring the phase difference between signals received at said first and second receiving means; (d) means for measuring the relative attenuation as between signals received at said first and second receiving means; and (e) means for generating a signal representative of the dielectric constant associated with the formations surrounding the area between the first and second receiving locations by combining the phase measurement with the attenuation measurement.
Claim 9
Dependent Claim
106 words
Apparatus for investigating earth formations surrounding a borehole, comprising: (a) means positionable in a borehole for injecting electromagnetic energy into the surrounding formations; (b) first and second receiving means positioned in spaced relation in the borehole; (c) means for measuring the phase difference between signals received at said first and second receiving means; (d) means for measuring the relative attenuation as between signals received at said first and second receiving means; and (e) means for generating a signal representative of the dielectric constant associated with the formations surrounding the area between the first and second receiving locations by combining the phase measurement with the attenuation measurement.
Claim 10
Dependent Claim
69 words
Apparatus as defined by claim 5 wherein the signal representative of the dielectric constant, .epsilon., of the formations of interest is generated in accordance with the relationship where .beta. and .alpha. are, respectively, phase and attenuation con-stants determined by the phase difference measuring means and the attenuation measuring means, .omega. is the angular frequency of the injected electromagnetic energy, and µ is the magnetic permeability of the surrounding formations.
Claim 11
Dependent Claim
72 words
Apparatus as defined by claim 6 wherein said generating means comprises: (f) means for deriving the quantity .beta.2, where .beta. is a phase constant determined by the phase difference measuring means; (g) means for deriving the quantity .alpha.2, where a is an attenuation constant determined by the attenuation measuring means; and (h) means for deriving the quantity .beta.2 - .alpha.2 which is proportional to the dielectric constant of the formations of interest.
Claim 12
Independent Claim
91 words
A method of determining the dielectric constant of formations surrounding the borehole, comprising the steps of: (a) injecting electromagnetic energy into the surrounding formations; (b) receiving energy signals at first and second receiving locations; (c) measuring the phase difference between the signals received at said first and second receiving locations; (d) measuring the relative attenuation as between signals received at said first and second receiving locations; and (e) generating a signal representative of the dielectric constant associated with the formations of interest by combining the phase measurement with the attenuation measurement.
Claim 13
Independent Claim
91 words
A method of determining the dielectric constant of formations surrounding the borehole, comprising the steps of: (a) injecting electromagnetic energy into the surrounding formations; (b) receiving energy signals at first and second receiving locations; (c) measuring the phase difference between the signals received at said first and second receiving locations; (d) measuring the relative attenuation as between signals received at said first and second receiving locations; and (e) generating a signal representative of the dielectric constant associated with the formations of interest by combining the phase measurement with the attenuation measurement.
Claim 14
Dependent Claim
68 words
The method as defined by claim 9 wherein the step of generating a signal includes the steps of: (f) deriving the quantity .beta.2, where .beta. is a phase constant determined from step (c); (g) deriving the quantity .alpha.2, where .alpha. is an attenuation constant determined from step (d); and (h) deriving the quantity .beta.2 - .alpha.2 which is pro-portional to the dielectric constant of the formations of interest.
Claim 15
Independent Claim
77 words
A method of determining the dielectric constant of formations surrounding a borehole, comprising the steps of: (a) deriving a quantity representative of the phase constant of the formations at a particular depth of the borehole; (b) deriving a quantity representative of the attenuation constant of the formations at the particular depth of the borehole; and (c) computing the dielectric constant associated with the formations at the particular depth by combining the phase measurement with the attenu-ation measurement.
Claim 16
Independent Claim
77 words
A method of determining the dielectric constant of formations surrounding a borehole, comprising the steps of: (a) deriving a quantity representative of the phase constant of the formations at a particular depth of the borehole; (b) deriving a quantity representative of the attenuation constant of the formations at the particular depth of the borehole; and (c) computing the dielectric constant associated with the formations at the particular depth by combining the phase measurement with the attenu-ation measurement.
Claim 17
Independent Claim
80 words
A method of determining the dielectric constant of formations surrounding a borehole, comprising the steps of: (a) deriving a quantity .beta.2, where .beta. is the phase constant associated with the formations at a particular depth of the borehole; (b) deriving a quantity .alpha.2, where .alpha. is the attenuation constant associated with the formations at the particular depth of the borehole; and (c) computing the quantity .beta.2-.alpha.2 which is proportional to the dielectric constant of the formations at the particular depth.
Claim 18
Independent Claim
80 words
A method of determining the dielectric constant of formations surrounding a borehole, comprising the steps of: (a) deriving a quantity .beta.2, where .beta. is the phase constant associated with the formations at a particular depth of the borehole; (b) deriving a quantity .alpha.2, where .alpha. is the attenuation constant associated with the formations at the particular depth of the borehole; and (c) computing the quantity .beta.2-.alpha.2 which is proportional to the dielectric constant of the formations at the particular depth.
References Cited (Backward Citations)
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