Guidelines and Partial List of Information Required for Pore Pressure Prediction

Prepared by BPI Baird Petrophysical for Our Clients.  Actual data shall be identified and agreed to between BPI and Client for the specific well and data available. Scales, quantities and selected data required will vary based on what is available at the time.

MAPS

1.      Digital or paper basemap, copies of structural maps, scales preferred: 1"=8000' or 1:100,000

*** Note regarding paper maps. We can use any form of map, paper or electronic; the scales need to reflect detail.

EXISTING OFFSET AND NEARBY WELL LOGS AND DATA

2.     One-inch (1"= 100 ft) paper electric logs, with resistivity and conductivity on a linear scale, for at least three (3) offset control wells (if available and appropriate) that penetrated the expected formations and on both sides of major faulting.  In addition to paper prints, LAS files, if available. More than three offset wells may be required if available.  Criteria for offset wells:

a.      Control wells not nearest the proposed location but along the same geologic trend, or for offshore, at the same water depth

b.     Control wells nearest the proposed drilling location, one to three wells drilled deep enough to be of value

3.     1=1000 ft and 1"=100 ft gamma ray and acoustic (sonic) logs for the same offsets.  For the 1"=1000 ft, the data should be smoothed to an order to be readable. LAS files, if available are preferred.

4.     Bulk density log from at least one of the same offset wells.  If possible the log should be integrated to determine the relationship of overburden gradient vs. depth.

5.     If available at least one sonic waveform analysis to include both compressional and shear velocities.  

*** Note regarding paper prints and digits (LAS): Accuracy is important: We prefer to have paper prints of all logs in addition to LAS (CLAS, LIS, BIT, ASCII) so that we can review the log headers for other information and to confirm the accuracy of the digitized logs.

SCOUT TICKETS, DAILY DRILLING REPORTS AND WELL DATA

6.     Scout tickets, mud logs and detailed drilling summaries for the offset wells above.  Daily drilling reports (morning reports) if detailed drilling summaries are not readily available.

7.     Any virgin BHP (bottom hole pressure) and current BHP information from any formations for the wells above.  RFT's, MDT's, FT's or other direct measurements of BHP.  

*** Note regarding paper reports: We accept paper or electronic forms of drilling reports and pressure data.

2D CROSS-SECTIONS AND 2D and 3D SEISMIC DATA

8.     Any cross-sections that are available and appropriate. Usually one strike and dip line are adequate. The purpose is to review the offset wells structure and stratigraphy and to trace the formations to be drilled away from the prospect into the basinal areas around the prospect's structure.

9.     Half scale (2.5"/sec or 5 cm/sec) interpreted 2D seismic lines, or 3D ARB lines which tie the proposed location to the offset control wells. Display should include wiggle, variable area in addition to displays used for prospect review. Electronic image files may be substituted for paper plot (call Baird to discuss).

10. Seismic base map showing the location of the offset wells, the proposed location and the seismic lines provided.

11. Time depth conversion table or chart for the area.

12. Pre-stack seismic data analysis. 2D-SIVA (cross-sections of semi-logarithmic Seismic ITT) curves from seismic velocity analysis or inversion for the offset wells at a scale of 1"=1000 ft (or 1=2000), with interval transit time plotted semi-log with 5" per log cycle.

In the absence of accurate and reliable 2D-SIVA curves, then the data and the means to create them.  This usually means raw seismic data tapes with observer data sheets and tape listing of shotpoints and field files on the tapes provided.  Usually 10 to 20 kilometers of 2D seismic data is required for each offset well. For 3D data, we prefer to go back to shot ordered field data to recover unprocessed seismic velocity information.

13. Similar 2D-SIVA curves for the proposed location.  If the well is directional then two or three SIVA curves may be necessary to cover the well path and to analyze separated fault blocks, areas away from the well and areas immediately around the well.

Again, if accurate and reliable SIVA curves are not available then the raw seismic data tapes are required in order to prepare and analyze the velocity trends at the proposed location.  Seismic gather tapes, trace sequential demultiplexed tapes or field tapes, prints of sections and support data:

a.      Preferred format is uncorrected gathers on tape or disk media in SEGY format, with geometry in the trace headers, when available.  Must provide processing details including any phase corrections, statics, velocity corrections and special processing details.  Baird must approve any processing provided.  Specifically data that retains and/or improves the minute detail of interval velocities are required.

b.     Include two or three lines over the proposed well location with the line length long enough to get off structure into syncline and non-faulted basinal areas.

c.      Include one or two lines over each control well.  These will be used to calibrate and study the drilling, logging, geologic and geophysical effects of normal and abnormal pressure.

d.     Include a base map showing the shotpoint locations and CDP/CMP numbering.

e.      Include any velocity analyses and/or velocity studies performed/available.

*** Data may be provided in electronic paper form. Usually the most expeditious form is preferred. We work with both electronic images and paper data.

GEOLOGIC PROSPECT INFORMATION

14. Geologic description of the prospect:

a.      Geologic age of each interval.

b.     Lithologic tops.

c.      Type of faulting (depositional, post-depositional) and anticipated depths.

d.     Environment (river channels, beaches)

e.      Targets and dimensions.

f.       Water depth.

g.      Primary and secondary objectives.

15. Paleo data and correlations.

SHALLOW HAZARDS REPORT

16. Shallow hazards report, if available. High resolution data prints and digital SEGY media may be requested/required.  

MISCELLANEOUS DATA

17. Temperature data, including log headings, mud logger and driller flowline temperature curves.

18. Any gravity maps and magnetic field measurement maps.

19. Well location coordinates

20. Well surface location water depth, for offshore wells

21. Existing well plan including preliminary mud weight and casing program, directional survey, proposed TD.

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