Continuous data seismic system

• US 6,188,962 B1
• Filed: 06/25/1998
• Issued: 02/13/2001
• Est. Priority Date: 06/25/1998
• Status: Expired due to Term

• Current Assignee: Reflection Marine Norge AS
• Original Assignee: Western Atlas International Incorporated (Northrop Grumman Corporation)
• Inventors: Morgan, Paul McDonald, Guyton, William Alfred, Williamson, Kenneth Graeme
• Primary Examiner(s): McElheny, Jr., Donald E.
• Application Number:
  US09/104,905
• Time in Patent Office: 964 Days
• Field of Search: 702/14, 702/16, 702/17, 702/18, 367/6, 367/76, 367/77, 367/16, 367/20, 367/117
• US Class Current: 702/14
• CPC Class Codes: G01V 1/003 Seismic data acquisition in general, e.g. survey design G01V1/3808, G01V1/42 take precedence
• CPC Class Codes: G01V 1/24 Recording seismic data

Abstract

A system for seismic data acquisition has been invented having, in certain aspects, one or multiple distributed data acquisition subsystems that are independent of energy source controller and/or of navigation system operation. Thus the distributed acquisition system(s) do not require a complicated and burdensome interface to the energy source controller or navigation systems. The seismic data acquisition system supplies a continuous flow of data which is buffered within a centralized data repository for short term storage until required by non-real-time processes. A seismic data acquisition method has been invented that replaces conventional closely coupled interaction between seismic acquisition systems and the energy source controller and the navigation systems by utilizing GPS time stamps on both the data as well as cycling events of the energy source controller and/or navigation systems to insure precise association of seismic data with cycling events. By continuously acquiring data with no interruption in the acquired data flow, association with energy source or navigation events may be accomplished at a latter point in time and not in the real-time operation of the acquisition subsystem.

Claims

1. A seismic data system comprising:

at least one seismic energy source having a GPS start time controlled by a seismic navigation system;

a seismic data acquisition subsystem for acquiring seismic precursor data, the precursor data comprising seismic reflections generated by the at least one seismic source;

GPS apparatus for providing current GPS time; and

an interface for continuously transmitting acquired seismic data and current GPS time to a data server, wherein the seismic data acquisition subsystem is operable independently of the GPS event start time for at least one seismic source.

2. A seismic data system comprising:

at least one seismic data acquisition subsystem for continuously acquiring seismic data generated by a seismic source having a GPS start time controlled by a seismic navigation system, the seismic data comprising reflected precursor data;

GPS apparatus for providing current GPS time tags for seismic data acquired by the at least one seismic data acquisition subsystem; and

an interface for continuously transmitting acquired seismic data and associated GPS information to a recording system wherein the at least one seismic data acquisition subsystem is operable for acquiring seismic precursor data and transmitting data to a data server, independently of the GPS event start time.

3. A seismic data acquisition system comprising:

a seismic navigation system for controlling a GPS start time for at least one seismic energy source;

a plurality of seismic data acquisition subsystems for acquiring seismic data, GPS apparatus for associating a GPS time tag to seismic data acquired by at least one of the seismic data acquisition systems;

at least one of the seismic data acquisition subsystems operable independently of the start time of the seismic source;

a data server subsystem for intermediate storage and retrieval of seismic data acquired by the seismic data acquisition subsystems, the data server subsystem able to use the GPS time tags as an identifying parameter for the acquired seismic data for storage and retrieval;

an event processor for non-real-time association of GPS time tagged acquired seismic data with corresponding GPS time tagged cycling event times;

an operator console for configuration, control, and real time monitoring of seismic data acquisition subsystems; and

the seismic data acquisition subsystems further comprising acquisition apparatus for continuously acquiring seismic data without associated dead time related to seismic energy source events initiated by the at least one seismic energy source.

4. A data reduction method comprising the steps of:

continuously recording geophysical seismic data independent of a GPS start time for a seismic event;

continuously recording the current GPS time along with the continuously recorded geophysical seismic data as GPS time stamp information; and

selecting a portion of the continuously recorded geophysical data recorded between a first earlier GPS time and a second later GPS time wherein the data record selected comprises a reconstruction of data recorded before and after the seismic event.

5. A seismic data method for acquiring and processing seismic data with a seismic data system comprising a plurality of seismic data acquisition subsystems operable independently of signals from a seismic navigation subsystem controlling an energy source start time and operable asynchronously with respect to the seismic navigation system, the method comprising the steps of:

continuously acquiring seismic data independently of the energy source GPS start time with the plurality of seismic data acquisition subsystems; and

continuously transmitting the acquired data to a server system.

6. The method of claim 5 wherein the seismic data system includes apparatus for applying current GPS time tagging information to the acquired seismic data and to energy source events, the method further comprising the steps of:

tagging the acquired seismic data with current GPS time; and

tagging signals representative of the energy source events with current GPS time.

7. The method of claim 6 wherein the seismic data system includes an event processor for real-time association of the current time tags to seismic events of the seismic data system and for non-real-time association of GPS time tagged acquired seismic data with corresponding GPS time tagged cycling events, the method further comprising the step of:

associating GPS tagged acquired seismic data with the GPS tagged signals.

8. The method of claim 7 further comprising the step of:

conducting the association of GPS tagged acquired seismic data with GPS tagged signals in non-real-time.

9. The method of claim 5 wherein the seismic data system includes the steps of:

applying GPS tagging information to acquired seismic data and to navigation system events;

GPS tagging the acquired seismic data; and

GPS tagging signals representative of the navigation system events.

10. The method of claim 9 wherein the seismic data system includes an event processor for real-time association of the GPS time tags acquired seismic data to cycling events of the seismic data system and for non-real-time association of GPS time tagged acquired seismic data with corresponding GPS time tagged cycling events and the method further comprising associating GPS tagged acquired data with the GPS tagged signals.

11. The method of claim 10 further comprising conducting the association of GPS tagged acquired seismic data with GPS tagged signals in non-real-time.

12. A method for acquiring seismic data comprising:

generating seismic data with a seismic energy system having a seismic energy source;

controlling a seismic energy source GPS start time with a seismic navigation system;

navigating the seismic energy system with a seismic navigation system;

continuously acquiring seismic data generated by the seismic energy system with a data acquisition system;

receiving current GPS time with a data system reception apparatus in the data acquisition system; and

selectively recording seismic data independently of the seismic navigation system GPS start time.

13. The seismic data method of claim 12 wherein the data acquisition system continuously acquires seismic data independently of signals from the seismic navigation system.

14. The method of claim 13 further comprising:

continuously transmitting seismic data acquired by the data acquisition system to a data server from the data acquisition system.

15. The method of claim 13 further comprising:

assembling on a tape recorder a seismic record including seismic data acquired by the data acquisition system, the assembly performed by a processing apparatus for assembly of a seismic record including at least a selected portion of the seismic data acquired by the data acquisition subsystem between a first GPS time and a second GPS time, the assembly occurring at a time later than a time of acquisition of the seismic data.

16. The method of claim 13 further comprising a step with an event processor for real-time association of the GPS time tags acquired seismic data to cycling events of the seismic data system and for non-real-time association of GPS time tagged acquired seismic data with corresponding GPS time tagged cycling events, and wherein said assembling occurs at a time later than a time of acquisition of the seismic data by the at least one seismic data acquisition subsystem, the method further comprising assembling a seismic record on a tape recorder with the event processor with a portion of selected acquired seismic data at a time later than a time of acquisition of the seismic data.

17. The method of claim 16 wherein the event processor further comprises processing apparatus for re-establishing time synchronization of acquired seismic data with events independent of the at least one seismic data acquisition subsystem, the method further comprising

re-establishing time synchronization of the acquired seismic data with the events independent of the plurality of seismic data acquisition subsystems.

18. The method of claim 17 wherein the re-establishing is done by interpolating to estimate a seismic data value for acquired seismic data relative to a time of specific cycling events.

19. A seismic data system comprising:

at least one seismic energy source, having a GPS start time controlled by a seismic navigation system;

at least one seismic data acquisition subsystem for acquiring seismic precursor data, the seismic precursor data comprising seismic reflections generated by at least one seismic source;

GPS apparatus for providing current GPS time;

the at least one seismic data acquisition subsystem for continuously acquiring seismic data and current GPS time, independent of the GPS start time of the seismic energy source; and

an interface for continuously transmitting acquired seismic data and GPS time from the data acquisition subsystem to a data server.

20. The seismic data system of claim 19 wherein the the at least one seismic data acquisition subsystem is operable independently of GPS time signals from the seismic navigation system.

21. The seismic data system of claim 19 wherein the at least one seismic data acquisition subsystem comprises a plurality of seismic data acquisition subsystems.

22. The seismic data system of claim 19 wherein an event processor, independent of the at least one data acquisition system uses the GPS time tags as an identifying parameter for the acquired seismic data for retrieving data from the data server.

23. The seismic data system of claim 22 wherein the event processor performs non-real-time association of GPS time tagged acquired seismic data with corresponding GPS time tagged cycling events.

24. The seismic data system of claim 23 wherein the event processor further comprises a processing apparatus for assembling on a single volume, a seismic record relative to GPS time tagged acquired seismic data.

25. The seismic data system of claim 23 wherein the event processor further comprises a processing apparatus for re-establishing time synchronization of acquired seismic data with seismic events.

26. The seismic data system of claim 25 wherein said re-establishing is done by temporal interpolation filtering between two GPS time tagged seismic data acquisition samples temporally surrounding a specific time requested by the event processor to estimate a seismic data value for acquired seismic GPS data at the specific time of specific cycling events.

27. The seismic data system of claim 19 further comprising:

an operator console for configuration, control, and real time monitoring of the at least one seismic data acquisition subsystem or a seismic sensor.

28. The seismic data system of claim 19 wherein the seismic data acquisition subsystem further comprises an acquisition apparatus with a master oscillator phase locked to a GPS disciplined clock.

29. A The seismic data system of claim 19 wherein the at least one seismic data acquisition subsystem further comprises an acquisition apparatus for continuously acquiring seismic data without associated dead time related to seismic energy source events initiated at GPS event start times by the at least one seismic energy source.

30. The seismic data system of claim 19 wherein the seismic data acquisition subsystem further comprises an acquisition apparatus for continuously acquiring seismic data without associated dead time related to navigation system events of the seismic navigation system.

31. The seismic data system of claim 19 further comprising:

a processor for performing real time monitoring one of the at least one seismic data acquisition subsystem or a seismic sensor.