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OrangeBasin
Post and Pre Salt plays are proven from Kwanza, Congo and Santos, Campos basins northward.
Whilst basins to the south are Salt free.
Q. Are all the plays in South Atlantic dependent on the presence of salt?
Q. So are there any sources,reservoirs or structures in theOrange Basin?
Walvis ridge
Q. Why do we need to establish the Hydrocarbon case for the Orange River Basin?
• Existing projects:
• Namcor Brokered data – 11,000km
• Veritas acquired data – 11,000km
• TGS Walvis JV data – 13,000km
• 2012 data – 16,000 km new data:• Orange Basin survey 50/50
ownership 8,165 km, • Luderitz Basin survey - 5,300 km• North Luderitz – 1,000 km acquired• AMIS S Walvis acquired –1,500 km
• Existing MC2D data test reprocessing• Phase 1 – 3 lines complete• Phase 2 - approx 4,000km
underway
Study Dataset
Basins with Source, Reservoir and Structure…
Yet only16 wells
7 into Kudu
500,000 km2
Hydrocarbon Play proven in the Barremian to Hauterivian in the 1.5 TCF Kudu gas field
Kabeljou Well (Petrobras/BP/Chariot) found Mature source
Oil Discoveries in Orange BasinIn South Africa
Orange River Basin
300km line
Post Rift
Pre Rift
Syn Rift
W E
Orange Basin Seismic
Hinge Rift Graben
Outer High
BUU
SDRs
Geological significance of gravity variations
Free air gravity
Hinge zone= reduced sedimentthickness
Break-Up-Unconformity (BUU)
Syn-Rift
Syn‐Rift Play
Syn Rift: Neocomian to Hauterivian Source Rock (Bucomazi Fm equiv)
Inboard Play system: Oil prone, extends up the margin, proven in Orange River Basin.
Pre BUU plays
SDR PlayOut-board SDR play
“Kudu” Barremian Aolian sst interbedded with Flood basalts
Pre BUU plays
BUU
Namibia: PSDM stack section. (Depth)
Structure : Depth Conversion
BUU
Outboard High
SDRs in 4-way dip closed structures; frequent along the margin
Pre BUU plays
140‐120 ma The South Atlantic: Hauterivian to Early Aptian
Extent of Aptian Depositional Evaporite Facies
(after Borsato et. al. 2012)
Orange
Ezanga, Loeme Salts
Pre BUU plays
Syn Rift Grabens – depositing lacustrine source rocks ( East African Rift Analogue)
Ariri, Alagoas Salts
Extent of Aptian Depositional Evaporite Facies
(after Borsato et. al. 2012)
Orange
Pre BUU plays
Late Aptian Syn‐rift – LIP Volcanism producing flood basalts of the SDR Phase.
Transition from SDR to MORB type Ocean Floor Basalt
“Transitional” Crust: Peneplaned marine transgressionMORB ocean floor basalt
Out-board high
Subsidence
MarineTransgression
Pre BUU plays
USGS 2006 after Tissot 1980
Wells Demonstrate Cenomanian-Turonian Source Rocks
Kabeljou Well (Petrobras/BP/Chariot) reportedly found Mature Cenomanian/ Turonian source
1: Syn Rift sequence:Inboard High Out Board HighHalf Graben trapsSDR traps
2: Post Rift sequence: Onlaps to Out Board HighDrape over Out Board High
3: Deltaic sedimentalogical Plays:Deepwater fansChannels
4: Deltaic Gravity playsTilted Fault BlocksSlumpsSlumps strat targets
Traps and plays
Conclusion
Conclusion
• Exciting area Very underexplored
• Source, Reservoir and structures, present in Pre-Break up Unconformity sequence
• Several Sources, Reservoir and structures, present in Post-Break up Unconformity sequence
• Large database of existing and new data
• The Presence of salt is not required for valid exploration plays on this margin.