Main Categories of Data

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• A. Borehole Related Data

  
  

  2.1 The following categories of geological samples originating from offshore wells are available for viewing, studying and analysis at the Petroleum Agency SA offices in Bellville:

  • Cores
  • Cuttings
  • Sidewall Cores
  • Microscope Slides

  Cores and geological samples originating from onshore boreholes are available from the Council for Geosciences in Pretoria.
  
  2.2 Geophysical Logs is available in digital TIFF format for printing or in original DLIS-, TLIS- or LIS or LAS Format.
  
  2.3 All well related reports can be supplied in digital TIFF or PDF format including related diagrams that was generated at the time of drilling the well.
  
  2.4 A Geological Well Completion Report normally contains a number of well related diagrams including but not limited to:

  2.4.1 A geophysical base log on scale of 1:500 (called a geological composite log). This log typically displays gamma ray, sonic interval velocity, deep and intermediate penetration resistivity, caliper, and in some cases self potential logs as well as a lithological interpretation.
  
  2.4.2 A litholog is based on the interpretation of borehole cores, side-wall cores and cuttings as well as dip meter and other geophysical logs, micropaleontology, petrography and geochemical data and reports. They attempt to integrate all relevant information to provide an optimal interpretation of sedimentological facies and depositional environments.
  
  2.4.3 Synthetic Seismogram
  
  2.4.4 Overpressure Detection Log

   

• B. Seismic Data

  
  

  A complete map and listing of seismic lines can be supplied for each seismic survey in the area of interest.
  
  Processed seismic data can be provided in digital TIFF format images and/or as digital processed SEGY format files for the majority of surveys.
  
  Survey field data acquired in 1976 and later years are stored on digital tape in original acquired format (SEGA, SEGB, SEGC and SEGD format).
  
  The chargeable length of seismic line will be calculated on the basis of the actual length of the whole line.
  
  Navigation data in digital ASCII format can be supplied free of charge with the purchase of seismic lines.
  
  Raw migrated seismic data are available for data processed from 1984 onwards. Some raw stack data are available for lines processed between 1981 to 1983. 
  
  Survey acquisition and processing reports are available and listed as Technical Reports.
  
  Separate listings can be provided for:

  • seismic lines (per length), seismic images, processed seismic SEGY data and field data.

• C. Magnetic Data

  
  

  A list of available gravity and magnetic data can be provided on request including:

  • Raw total magnetic field
  • Leveled total magnetic field
  • Reduced to pole total magnetic field (gridded)

• D. Technical Reports

  
  

  All relevant technical reports that are available and categorized  as follows:

  1. Well Reports:  These are borehole specific reports that includes Recommendation Reports for wells that have not been drilled
  2. Regional Reports: The offshore area is divided into West, South and East Coast Regional Reports.
     Blocks 1-6 West Coast
     Blocks 7-14 South Coast
     Blocks 15-18 East Coast
     Reports dealing with two or more blocks are set out under the heading Regional Reports.
  3. Offshore General Reports - reports dealing with more than one region or that are of general relevance to the offshore are set out separately.
  4. Onshore technical reports are available for exploration activities being carried out in the late 1960’s in the Karoo, Zululand and Algoa basins.