Method of reconstituting seismic data

• US 4,751,655 A
• Filed: 06/11/1986
• Issued: 06/14/1988
• Est. Priority Date: 06/11/1986
• Status: Expired due to Fees

• Current Assignee: Amoco Corporation Chicago Illinois
• Original Assignee: Amoco Corporation (BP PLC)
• Inventors: Peacock, Kenneth L.
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): Goldman, David C.
• Application Number:
  US06/872,994
• Time in Patent Office: 734 Days
• Field of Search: 364/572, 364/577, 364/481, 364/421, 364/724, 364/487, 346/33 C, 367/74, 367/21, 367/38, 367/43, 367/47, 367/68, 367/66, 367/64, 367/28-29, 324/77 R, 324/77 CS, 328/54, 328/53, 328/165, 328/167
• US Class Current: 702/189
• CPC Class Codes: G01V 1/32 Transforming one recording into another or one representation into another
• CPC Class Codes: G01V 2210/40 Transforming data representation for pre-filtering purposes G01V2210/20
• CPC Class Codes: H03H 17/02 Frequency selective networks digital computers for complex mathematical operations G06F17/10

Abstract

At least two methods of reconstituting the original form of a time/amplitude trace, such as seismic data, are disclosed wherein the seismic data has been rectified by a scanner to produce a signal representative of a hardcopy display of the trace. One of the methods comprises selecting a time window of a certain duration, obtaining a measurement of the predominant period within the selected positive components of the signal, and filtering the signal with a bandpass filter having a range of about F/2 to about 3F/2, where F equals the reciprocal of the predominant period of the signal.

Claims

1. A method of reconstituting a time/amplitude trace, which has been rectified by a scanner to produce a signal representative of a hardcopy display of the time/amplitude trace, comprising:

(a) selecting a time window of a certain duration;

(b) obtaining a measurement of a predominant period of the signal within the selected time window; and

(c) filtering the signal with a bandpass filter having a range of about F/2 to about 3F/2, where F equals the reciprocal of the predominant period of the signal.

2. The method of claim 1 wherein step (b) comprises counting positive components within the selected time window.

3. The method of claim 1 wherein step (c) comprises a band-limited interpolator to restore missing portions of the signal.

4. A method of reconstituting a time/amplitude trace, which has been rectified by a scanner to produce a signal representative of a hardcopy display of the time/amplitude trace, comprising:

(a) selecting positive components of the signal;

(b) determining which positive components of (a) have been amplitude clipped;

(c) rejecting determined amplitude clipped components; and

(d) interpolating nonrejected positive components of the signal to reconstitute the time/amplitude trace.

5. The method of claim 4 whereien step (d) includes using cubic-spline interpolation.

6. The method of claim 4 and including a step (e) which comprises bandpass filtering the signal of (d).

7. A method of reconstituting a time/amplitude trace, comprising:

(a) passing an optical scanner device across a time/amplitude trace of a seismic section to produce a signal for the time/amplitude trace

(b) selecting positive components of the signal

(c) determining which of the positive components of the signal have been amplitude clipped and rejecting all components of the signal that have been amplitude clipped; and

(d) interpolating nonrejecting positive components of the signal to reconstitute the time/amplitude trace.