Patent US3736556A successfully refreshed from Google Patents.
US3736556A
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Method and apparatus for increasing seismic signal-to-noise ratio
Assignee: Halliburton Geophysical Services Inc
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Filing: 1971-09-08
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Granted: 1973-05-29
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Expires: 1991-09-08
Abstract
Abstract An improved technique for enhancing the signal-to-noise ratio in the automatic processing of seismic data is provided according to the present invention. Signals from horizontally and vertically oriented geophones, representing two functions of time, are separately recorded. The product of these two signals is formed as a signal representative of a third function of time. The product signal thus formed is then used in various ways as an ''''enhancement function'''' signal, to attenuate noise components and enhance seismic signal components. One technique for utilizing the enhancement function signal involves half-wave rectifying the enhancement function signal and then multiplying the rectified signal by the original signal from the vertically oriented geophone. Another technique involves using the enhancement function signal to produce a gating signal to cancel the original output signal from the vertically oriented geophone whenever the enhancement function signal is other than negative.
Inventors
- 👤 F Barr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:46
CPC Classifications
G; G01; G01V; G01V1/00; G01V1/28; G01V1/284
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
237 words
A seismic data processing method comprising the steps of: a. Placing a first geophone in a position such that it is principally sensitive to energy received from a horizontal direction; b. placing a second geophone near said first geophone, such that it is principally sensitive to energy received from a vertical direction; c. receiving signals from the earth in said first and second geophones; d. recording the outputs of said first and second geophones as signals representative of first and second functions of time, respectively; e. multiplying said signal representative of a first function of time by said signal representative of a second functiOn of time to produce a signal representative of a third function of time; f. positive half-wave rectifying said signal representative of a third function of time to produce a signal representative of a fourth function of time; g. multiplying said signal representative of a fourth function of time by said signal representative of a second function of time to produce a signal representative of a fifth function of time; and h. filtering said signal representative of a fifth function of time to remove therefrom frequency components higher than the seismological range of interest, to produce a signal representative of a sixth function of time; said signal representative of a sixth function of time having a higher ratio of seismic signal to seismic noise than said signal representative of a second function of time.
Claim 2
Dependent Claim
237 words
A seismic data processing method comprising the steps of: a. Placing a first geophone in a position such that it is principally sensitive to energy received from a horizontal direction; b. placing a second geophone near said first geophone, such that it is principally sensitive to energy received from a vertical direction; c. receiving signals from the earth in said first and second geophones; d. recording the outputs of said first and second geophones as signals representative of first and second functions of time, respectively; e. multiplying said signal representative of a first function of time by said signal representative of a second functiOn of time to produce a signal representative of a third function of time; f. positive half-wave rectifying said signal representative of a third function of time to produce a signal representative of a fourth function of time; g. multiplying said signal representative of a fourth function of time by said signal representative of a second function of time to produce a signal representative of a fifth function of time; and h. filtering said signal representative of a fifth function of time to remove therefrom frequency components higher than the seismological range of interest, to produce a signal representative of a sixth function of time; said signal representative of a sixth function of time having a higher ratio of seismic signal to seismic noise than said signal representative of a second function of time.
Claim 3
Dependent Claim
54 words
The method according to claim 1 wherein said placing steps are performed such that the sensitivity axis of said first geophone is inclined at an angle to a horizontal plane, and the sensitivity axis of said second geophone is inclined at an angle to a vertical plane, said axes being perpendicular to each other.
Claim 4
Dependent Claim
28 words
The method according to claim 1, wherein said placing of said first geophone is such that a shot point lies on the sensitivity axis of said first geophone.
Claim 5
Independent Claim
95 words
A method of processing seismic signals in the presence of seismic noise, comprising the steps of: a. Generating first and second signals respectively representative of waves received from a generally horizontal direction and a generally vertical direction; b. multiplying the first signal by the second signal to produce a third signal; c. removing the negative components of the third signal to produce a fourth signal; and d. multiplying the fourth signal by the second signal, thereby producing a fifth signal in which the seismic signals have been enhanced and the seismic noise has been attenuated.
Claim 6
Independent Claim
95 words
A method of processing seismic signals in the presence of seismic noise, comprising the steps of: a. Generating first and second signals respectively representative of waves received from a generally horizontal direction and a generally vertical direction; b. multiplying the first signal by the second signal to produce a third signal; c. removing the negative components of the third signal to produce a fourth signal; and d. multiplying the fourth signal by the second signal, thereby producing a fifth signal in which the seismic signals have been enhanced and the seismic noise has been attenuated.
Claim 7
Dependent Claim
25 words
The method according to claim 4, further comprising the step of removing from the fifth signal frequency components higher than the seismological range of interest.
Claim 8
Dependent Claim
18 words
The method according to claim 5 wherein said removing step is accomplished by band-pass filtering said fifth signal.
Claim 9
Dependent Claim
29 words
The method according to claim 4, further comprising the step of recording the first and second signals before said step of multiplying said first signal by said second signal.
Claim 10
Independent Claim
93 words
A method of processing signals representative of geophysical data, comprising the steps of: a. Generating first and second signals respectively representative of waves received from a generally horizontal direction and a generally vertical direction; b. multiplying the first signal by the second signal to produce a third signal; c. removing the negative components of the third signal to produce a fourth signal; and d. multiplying the fourth signal by the second signal to produce a fifth signal, said fifth signal having a higher seismic signal to seismic noise ratio than said second signal.
Claim 11
Independent Claim
93 words
A method of processing signals representative of geophysical data, comprising the steps of: a. Generating first and second signals respectively representative of waves received from a generally horizontal direction and a generally vertical direction; b. multiplying the first signal by the second signal to produce a third signal; c. removing the negative components of the third signal to produce a fourth signal; and d. multiplying the fourth signal by the second signal to produce a fifth signal, said fifth signal having a higher seismic signal to seismic noise ratio than said second signal.
Claim 12
Dependent Claim
25 words
The method according to claim 8, further comprising the step of removing from the fifth signal frequency components higher than the seismological range of interest.
Claim 13
Dependent Claim
19 words
The method according to claim 9 wherein said removing step is accomplished by band-pass filtering of said fifth signal.
Claim 14
Dependent Claim
29 words
The method according to claim 8, further comprising the step of recording the first and second signals before said step of multiplying said first signal by said second signal.
Claim 15
Dependent Claim
118 words
Apparatus for processing seismic signals in the presence of seismic noise, comprising; a. a first geophone mounted so as to be principally sensitive to energy received from a horizontal direction; b. a second geophone mounted so as to be principally sensitive to energy received from a vertical direction; c. first multiplying means, for multiplying the output signal of said first geophone by the output signal of said second geophone; d. means for positive half-wave rectifying the oUtput of said first multiplying means; e. second multiplying means, for multiplying the output of said half-wave rectifying means by the output of said second geophone; and f. means for filtering undesired higher-frequency components from the output of said second multiplying means.
Claim 16
Dependent Claim
118 words
Apparatus for processing seismic signals in the presence of seismic noise, comprising; a. a first geophone mounted so as to be principally sensitive to energy received from a horizontal direction; b. a second geophone mounted so as to be principally sensitive to energy received from a vertical direction; c. first multiplying means, for multiplying the output signal of said first geophone by the output signal of said second geophone; d. means for positive half-wave rectifying the oUtput of said first multiplying means; e. second multiplying means, for multiplying the output of said half-wave rectifying means by the output of said second geophone; and f. means for filtering undesired higher-frequency components from the output of said second multiplying means.
Claim 17
Dependent Claim
19 words
Apparatus according to claim 12, further comprising means for recording the output signals of said first and second geophones.
Claim 18
Dependent Claim
145 words
A seismic data processing method comprising the steps of: a. Placing a first geophone in a position such that it is principally sensitive to energy received from a horizontal direction; b. placing a second geophone near said first geophone, such that it is principally sensitive to energy received from a vertical direction; c. receiving signals from the earth in said first and second geophones; d. recording the outputs of said first and second geophones as signals representative of first and second functions of time, respectively; e. multiplying said signal representative of a first function of time by said signal representative of a second function of time to produce a signal representative of a third function of time; f. cancelling said signal representative of a second function of time during time intervals when said signal representative of a third function of time is other than positive.
Claim 19
Dependent Claim
145 words
A seismic data processing method comprising the steps of: a. Placing a first geophone in a position such that it is principally sensitive to energy received from a horizontal direction; b. placing a second geophone near said first geophone, such that it is principally sensitive to energy received from a vertical direction; c. receiving signals from the earth in said first and second geophones; d. recording the outputs of said first and second geophones as signals representative of first and second functions of time, respectively; e. multiplying said signal representative of a first function of time by said signal representative of a second function of time to produce a signal representative of a third function of time; f. cancelling said signal representative of a second function of time during time intervals when said signal representative of a third function of time is other than positive.
Claim 20
Dependent Claim
28 words
The method according to claim 14, further comprising the step of removing, from the signal remaining after said cancelling step, frequencies higher than the seismological range of interest.
Claim 21
Dependent Claim
18 words
The method according to claim 15 wherein said removing step is accomplished by band-pass filtering said remaining signal.
Claim 22
Dependent Claim
91 words
Apparatus for processing seismic signals in the presence of seismic noise, comprising: a. a first geophone mounted so as to be principally sensitive to energy received from a horizontal direction; b. a second geophone mounted so as to be principally sensitive to energy received from a vertical direction; c. means for multiplying the output signal of said first geophone by the output signal of said second geophone; d. means for cancelling the output of said second geophone during time intervals when the output of said multiplying means is other than positive.
Claim 23
Dependent Claim
91 words
Apparatus for processing seismic signals in the presence of seismic noise, comprising: a. a first geophone mounted so as to be principally sensitive to energy received from a horizontal direction; b. a second geophone mounted so as to be principally sensitive to energy received from a vertical direction; c. means for multiplying the output signal of said first geophone by the output signal of said second geophone; d. means for cancelling the output of said second geophone during time intervals when the output of said multiplying means is other than positive.
Claim 24
Dependent Claim
19 words
Apparatus according to claim 17, further comprising means for recording the output signals of said first and second geophones.
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) | 1976-05-28 | 1976-11-27 | 1977-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-28 | 1980-11-27 | 1981-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-28 | 1984-11-27 | 1985-05-29 | $7700.00 | Window Closed / Lapsed |