Patent US4671379A successfully refreshed from Google Patents.
US4671379A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for generating seismic waves
Assignee: Petrophysical Services Inc
•
Filing: 1985-09-03
•
Granted: 1987-06-09
•
Expires: 2005-09-03
Abstract
Abstract A method and apparatus for generating a seismic wave in a borehole in the earth is disclosed. A portion of the borehole, which may be the bottom of the hole or any other point along its length, is selected as the site for seismic wave generation. A device is provided to oscillate the borehole fluid in a selected portion of the borehole to establish a resonant standing pressure wave of desired frequency within the fluid. The wave is maintained by continuing to supply energy to the fluid to replace losses due to fluid friction, structural losses and radiated acoustic energy. The standing wave thus created is radiated through the borehole wall into the earth and is eventually received by seismic detectors located on the surface.
Inventors
- 👤 William S. Kennedy
- 👤 Stephen J. Blumenkranz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:11
CPC Classifications
G; G01; G01V; G01V1/00; G01V1/003; G01V1/005; G01V1/02; G01V1/133; G01V1/135; Y; Y10; Y10S; Y10S181/00; Y10S181/40; Y10S181/401
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
107 words
A method for creating seismic waves in the earth from a borehole comprising the steps of: (a) providing first and second end means in said borehole, said first and second end means being vertically spaced apart a preselected distance to define a borehole space therebetween; (b) providing a fluid in said borehole space; (c) exciting said fluid into oscillation within the borehole space between said first and second end means, said fluid being oscillated at a frequency sufficient to create and maintain a resonant standing pressure wave between said first and second end means; and (d) varying the resonant frequency of oscillation over a range of frequencies.
Claim 2
Independent Claim
107 words
A method for creating seismic waves in the earth from a borehole comprising the steps of: (a) providing first and second end means in said borehole, said first and second end means being vertically spaced apart a preselected distance to define a borehole space therebetween; (b) providing a fluid in said borehole space; (c) exciting said fluid into oscillation within the borehole space between said first and second end means, said fluid being oscillated at a frequency sufficient to create and maintain a resonant standing pressure wave between said first and second end means; and (d) varying the resonant frequency of oscillation over a range of frequencies.
Claim 3
Dependent Claim
32 words
The method of claim 1 wherein said fluid is excited in a pulsating fashion at a frequency selected to establish resonance in the borehole space between said first and second end means.
Claim 4
Dependent Claim
26 words
The method of claim 1 wherein said preselected distance is determined and varied so as to provide resonant frequencies in a frequency useful for seismic signals.
Claim 5
Dependent Claim
21 words
The method of claim 3 wherein said preselected distance is one-half the wavelength of said resonant frequencies useful for seismic signals.
Claim 6
Dependent Claim
24 words
The method of claim 3 wherein said preselected distance is one quarter of the wavelength of a preselected resonant frequency useful for seismic signals.
Claim 7
Independent Claim
25 words
The method of either of claims 3 or 4 wherein said resonant frequency is in the range of about 10 Hz to about 200 Hz.
Claim 8
Independent Claim
84 words
An apparatus for generating a seismic wave in a borehole containing a fluid comprising: (a) a pair of end means positioned in said borehole and separated from each other by a preselected vertical distance; (b) means communicating with the fluid in said borehole space between said end means for inducing oscillations in said fluid whereby the fluid within said space generates a resonant standing pressure wave; and (c) means for varying the resonant frequency of oscillation of said fluid over a range of frequencies.
Claim 9
Independent Claim
84 words
An apparatus for generating a seismic wave in a borehole containing a fluid comprising: (a) a pair of end means positioned in said borehole and separated from each other by a preselected vertical distance; (b) means communicating with the fluid in said borehole space between said end means for inducing oscillations in said fluid whereby the fluid within said space generates a resonant standing pressure wave; and (c) means for varying the resonant frequency of oscillation of said fluid over a range of frequencies.
Claim 10
Dependent Claim
23 words
The apparatus of claim 7 wherein at least one of said end means includes a compressible volume in communication with said oscillatory fluid.
Claim 11
Dependent Claim
14 words
The apparatus of claim 8 wherein said compressible volume comprises a gas filled bladder.
Claim 12
Dependent Claim
20 words
The apparatus of claim 9 wherein said gas is selected from the group comprising hydrogen, helium, methane, air, and nitrogen.
Claim 13
Dependent Claim
10 words
The apparaturs of claim 10 wherein said gas is helium.
Claim 14
Independent Claim
33 words
The apparatus of any of claims 7 through 11 wherein said means for varying the resonant frequency comprises means for moving at least one of said end means with respect to the other.
Claim 15
Independent Claim
20 words
The apparatus of any of claims 7 through 11 wherein said fluid located in said borehole space is drilling mud.
Claim 16
Dependent Claim
22 words
The apparatus of claim 7 wherein at least one of said end means is in rigid fluid tight contact with said borehole.
Claim 17
Dependent Claim
32 words
The apparatus of claim 14 wherein one of said end means is in rigid fluid tight contact with said borehole and the other of said end means includes a compressible gas bladder.
Claim 18
Independent Claim
119 words
An apparatus for use in a borehole containing fluid for generating a seismic wave in the earth, said apparatus comprising: (a) first and second end means positioned in said borehole and separated from each other by a predetermined vertical distance, said first and second end means each including a compressible gas filled bladder; (b) connecting means between said first and second end means and including a central portion; (c) means housed within said central portion for inducing oscillations in said fluid between said first and second end means, whereby the oscillations of said drilling fluid generate a resonant standing pressure wave; and (d) means for varying the resonant frequency of oscillation of said fluid over a range of frequencies.
Claim 19
Independent Claim
119 words
An apparatus for use in a borehole containing fluid for generating a seismic wave in the earth, said apparatus comprising: (a) first and second end means positioned in said borehole and separated from each other by a predetermined vertical distance, said first and second end means each including a compressible gas filled bladder; (b) connecting means between said first and second end means and including a central portion; (c) means housed within said central portion for inducing oscillations in said fluid between said first and second end means, whereby the oscillations of said drilling fluid generate a resonant standing pressure wave; and (d) means for varying the resonant frequency of oscillation of said fluid over a range of frequencies.
Claim 20
Dependent Claim
52 words
The apparatus of claim 16 wherein said means for inducing oscillations comprises a moveable diaphragm in contact on one side thereof with said fluid and in fluid communication on the other side thereof with a reciprocable piston, whereby the reciprocating motion of said piston causes a corresponding displacement of said moveable diaphragm.
Claim 21
Dependent Claim
45 words
The apparatus of claim 16 wherein said means for varying the resonant frequency comprises means for moving said first and second end means relative to each other whereby the natural resonant frequency of the fluid column therebetween may be varied over a range of frequencies.
Claim 22
Independent Claim
121 words
An apparatus for generating a seismic wave in the earth from a borehole containing fluid, said apparatus comprising: (a) first non-compressible end means positioned in said borehole in fluid tight position; (b) second end means vertically spaced from said first end means in said borehole, said second end means including a compressible gas bladder facing said first end means; (c) means located in said first end means for exciting said borehole fluid into oscillation between said first and second end means at a frequency of oscillation sufficient to create and maintain a resonant standing pressure wave between said first and second end means; and (d) means for varying the resonant frequency of oscillation of said fluid over a range of frequencies.
Claim 23
Independent Claim
121 words
An apparatus for generating a seismic wave in the earth from a borehole containing fluid, said apparatus comprising: (a) first non-compressible end means positioned in said borehole in fluid tight position; (b) second end means vertically spaced from said first end means in said borehole, said second end means including a compressible gas bladder facing said first end means; (c) means located in said first end means for exciting said borehole fluid into oscillation between said first and second end means at a frequency of oscillation sufficient to create and maintain a resonant standing pressure wave between said first and second end means; and (d) means for varying the resonant frequency of oscillation of said fluid over a range of frequencies.
Claim 24
Dependent Claim
61 words
The apparatus of claim 19 wherein said means for exciting said borehole fluid comprises at least one moveable diaphragm mounted in said first end means in contact with said borehole fluid on one side thereof and in fluid communication with a reciprocable piston on the other side thereof, whereby reciprocation of said piston causes a corresponding displacement of said moveable diaphragm.
Claim 25
Dependent Claim
33 words
The apparatus of claim 16 wherein said means for varying the resonant frequency comprises an elastic sleeve fitted about at least a portion of said connecting means and means for inflating said sleeve.
Claim 26
Dependent Claim
27 words
The apparatus of claim 9 wherein said means for inducing oscillations in said fluid comprises means for oscillating at least a portion of said gas filled bladder.
Claim 27
Dependent Claim
37 words
The method of claim 3 wherein said preselected distance is one-quarter of the wavelength of said resonant frequencies useful for seismic signals and wherein said first end means is in rigid fluid tight contact with said borehole.
References Cited (Backward Citations)
US2281751A
Cited
US2433746A
Cited
US2451797A
Cited
US3221833A
Cited
US3349867A
Cited
US3730269A
Cited
US3718205A
Cited
US3909776A
Cited
US4040003A
Cited
US3997021A
Cited
US4033429A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-08 | 1990-12-08 | 1991-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-08 | 1994-12-08 | 1995-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-08 | 1998-12-08 | 1999-06-09 | $7700.00 | Window Closed / Lapsed |