Western Bredasdorp Basin: Prospects for Petroleum Exploration

1. PETROLEUM EXPLORATION AND PRODUCTION ACTIVITIES IN SOUTH AFRICA • Onshore: • 18 companies and their subsidiaries • about 40 ERs • 3 TCPs • about 100 applications Offshore: 8 international and 2 local companies active in 21 concessions with 7 areas under application Onshore - CBM, Shale gas Offshore – conventional oil and gas

2. Western Bredasdorp Basin OPEN ACREAGE Jacques Roux September 2010

3. Outline • Historic and geological overview • Structural evolution of open acreage • Prospects in the Southern Sub-basin • Summary of prospectivity

4. Historic and geological overview

5. Western Bredasdorp Basin exploration opportunities

6. Stratigraphic pinch-out against Central High • P50 estimate of STOIIP = 129 Mmbbl • Volumetrics based on closing contour within open acreage PROSPECT P6: RINKHALS LEAD Mass-flow Hauterivian structure overlying 5At1

7. Structural evolution of open acreage

8. I.Mid-Jurassic to Valanginian:SYNRIFT I PHASE II. Late Valanginian to Hauterivian: SYNRIFT II PHASE III.Hauterivian to Aptian: TRANSITIONAL (EARLY DRIFT) PHASE IV.Albian to Maastrichtian: DRIFT PHASE V.Paleocene to Present Day:UPPER DRIFT PHASE Schematic illustration of the structural evolution of the Western Bredasdorp Basin

9. Lower part of Synrift II isopach (Late-Valanginian toEarly-Hauterivian succession) 5At1 truncates 1At1 Pinch-out of 5At1-to-6At1 sequence against 1At1 The Arniston Half-graben experienced further deepening with slope deposits comprising interbedded sandstone and claystone as intersected in the D-B1 well. The Southern Sub-basin seems less developed, but several bright seismic anomalies suggest possible basin floor fan development.

10. Upper part of Synrift II isopach (Hauterivian succession) 5At1 truncates 1At1 The Arniston Half-graben as well as the Southern Sub-basin indicate major thickening resulting from subsidence of these depocentres during this Synrift II stage, which favoured the deposition of Hauterivian age oil-prone source rocks as intersected in the Arniston Half-graben.

11. Early drift isochron (Late Hauterivian-to-Mid Aptian succession) Shelf-edge Base of slope Proven oil to wet-gas prone source rocks and basin floor fan development in the Southern Sub-basin as was the case in producing Central Bredasdorp Basin.

12. Prospects in Southern Sub-basin

13. Prospect P3: Updip potential at Mid Hauterivian level

14. Updip potential of D-A1 well

15. Assumptions: 10% porosity, 15m ave net pay, 70% oil saturation 75% formation factor Upside potential (STOIIP) = 88 MMbbl Prospect P3: Updip potential at Mid Hauterivian level

16. Prospect P17: Hauterivian bff in Southern Sub-basin

17. E Area of bright seismic anomaly covers 9.1 km² • Assumptions: • 20% porosity • 30m ave net pay • 70% oil saturation • Most likely estimate STOIIP • = 62 MMbbl E’ Prospect P17: Depth map to top of 5A basin floor fan

18. E’ E 13At1 Top of Prospect P17 6At1 5At1 Basement Top synrift Prospect P17: Hauterivian basin floor fan

19. F K’ K F’ Prospects P11 & P12: Hauterivian fans within the Southern Sub-basin

20. K’ K • Assumptions: • 20% porosity, • 30m ave net pay, • 70% oil saturation • 0.75 formation factor Areal closure of trap …= 16.9 km² (P11) • …= 4.9 km² (P20) • Most likely estimate P11: • 112 MMbbl in place • Most likely estimate P20: • 31 MMbbl in place Prospect P11 Prospect P20 6At1 5At1 Top synrift Basement Prospects P11 and P20: Basin floor fans within the Southern Sub-basin

21. F F’ Seafloor 15At1 Projected Prospect 4 13At1 13Amfs Top synrift Prospect P11 6At1 5At1 Basement Hauterivian oil-prone source Migration route Source rocks and potential migration routes within the Southern Sub-basin

22. J J’ Prospect P4: Barremian age closure

23. Prospect P4: Depth map to top of Barremian target J’ Top of target onlaps exposed Synrift I red and green claystones Domal closure =11.9 km² • Assumptions: • 20% porosity, • 15m ave net pay, • 70% oil saturation • 0.8 formation factor • Domal closure = 11.8 km² • Upside estimate of domal trap: • = 124 MMbbl in place • Most likely estimate =41 MMbbl STOIIP J

24. Prospect P4: Seismic profile illustrating domal trap and charge

25. Prospect P4: Aptian prospects

26. Assumptions: • 20% porosity, • 30m ave net pay, • 70% oil saturation • 0.75 formation factor Areal closure of trap …= 11.7 km² (P18) • …= 7.7 km² (P19) • Most likely estimate P18: • 77 MMbbl in place • Most likely estimate P19: • 51 MMbbl in place Prospect P18 N N’ M Prospect P19 Open acreage Block 9 M’ Prospects P18 and P19: TWT map to top of target

27. Prospect P18: Seismic profile illustrating Aptian channel feature Gamma ray Φ= 25%, good permeability assured by secondary Φ; 36m Nett Ssts Inner shelf Ssts, minor Clsts N’ N 13At1 13At1 Aptian unconformity Transitional interbeds comprising red Clsts, Sltsts and Ssts Φ= 20-25%, 24m Nett Ssts 13Amfs Channel sandstones reflects a soft seismic signal 13At1

28. Summary of prospectivity

29. Summary of prospectivity • 21 prospects delineated • Proven oil & wet-gas prone source rocks • Short migration routes and effective charge • Oil expulsion throughout the Tertiary • Geological risk low on all aspects except seal • Central High area affected by intrusion activity 55 million years ago • Proven reservoir rocks • Potential hydrocarbon accumulations associated with bright spots