lake albert rift basin – exploration...
TRANSCRIPT
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 1
INTERIM RESULTS - 06
Lake Albert Rift Basin – Exploration Campaign
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 2
Lake Albert Rift Basin Exploration - Presentation Outline
Lake Albert Rift Basin Geology
• Regional setting• What is a Rift Basin?• Petroleum system• Early exploration history
Current Exploration Campaign• Acreage• Basin-wide strategy
Building blocks for threshold export volume• Prospect funnel• Building blocks
Exploration Summary• Strategy• Resource volumes
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 3
INTERIM RESULTS - 06
Lake Albert Rift Basin Geology
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 4
Regional Setting: East Africa Rift System
• Linked intra-continental Rift Basins
• 3500 km long, 50-150km wide
• Two dominant trends; eastern and western branch
• Eastern branch, initiated Early Miocene (20 Ma), is more volcanic
• Western branch, initiated during Late Miocene (10 Ma), contains lakes e.g. Lake Malawi, Lake Tanganyika and Lake Albert
ARABIAN PLATE
AFRICAN PLATE
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 5
Regional Setting: Topography, rivers & lakes
Courtesy Chris Scholz, Syracuse University
DRC
Uganda
Lake Albert(140 km by 40 km)
LakeEdward Ruwenzori
(16,761 ft)permanent snow
Nile Valley
30o 31o 32o 33o 34o
3o
2o
1o
0
-1o
-2o
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 6
Image © Research Machines plc
Rift Basins
• Separation of tectonic plates above deep-seated plumes of magma
• Brittle upper crust is faulted creating traps for oil
• Earthquake activity
• Magma feeds volcanoes
• Rift valleys form and are filled by lakes and sediments
• Heat and burial matures organic rich shales which expel oil into reservoir sands
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 7
Earthquakes and Volcanoes in East Africa Rift System
• Earthquakes influence lake water levels, topography and sedimentation• Volcanoes influence heat flow, oil source rock maturation and CO2
Depth in KmMagnitude1
66
Depth in KmMagnitude1
66
Depth in KmMagnitude1
66
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 8
Lake Albert Rift Basin Shales: Source Rocks
1200
1100
1000
900
800
700
600
500
400
300
200
100
M M
ioce
neU
Mio
cene
-Plio
cene
Low
er M
ioce
ne to
Plio
cene
Wak
iFor
mat
ion
Kls
egiF
orm
atio
nK
also
Form
atio
n
Qua
rtern
ary
Ear
ly P
leis
toce
ne
m
Waki-1 (1937)
“Asphaltic oil” at 1173 m
6-7% organic content in bituminous shale below
750m with some extractable oil
Turaco-1 (2001)
Shallow section:
Land plant dominated potentially gas generating source rock
Generally immature
Deeper section:
Amorphous algal dominated oil generating source rock
Generally mature
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 9
Lake Albert Rift Basin Source Rock Kitchen
• Lake Albert bathymetry map mimics depth to source rock kitchen
DEEP
KaisoTonya
ButiabaSHALLOW
DRC
UGANDA
migration paths
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 10
Lake Albert Rift Basin Natural Oil Seeps and Slicks
Mswa
Kasenyi
Kibiro
Hohwa Oil Sands
Paraa
Kibuku
Kabyosi
Oil seepsSAR slicks
Hohwa oil impregnated
sandstone Kaiso-Tonya
Naturaloil film on Nile at Paraa
• Abundant surface oil seeps (no sulphur, waxy, 30-34˚ API in wells)• “Synthetic Aperture Radar” (SAR) slicks on lake
Kibuku Oil Seep
SemlikiOil Seep in crushed basementat KabyosiKaiso–Tonya
Kibiro Oil Seep Butiaba
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 11
Lake Albert Rift Basin Environments of Deposition
Braidplain - beaches
Rift scarp cut by wadis
Delta with associated reservoir facies
Incised channel System. Main input
point in basin
Active fault system
Apron fan
Small Incised channel system
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 12
Lake Albert Rift Basin Reservoirs
• Diverse environments of deposition○ Scree / apron fans○ River channels○ Deltas○ Beaches and bars○ Submarine fans
• Generally thick well sorted sandstones
• Good porosities (27-32%)
• Good permeability (200-8,000 mD)
• High flow rates (800-4,500 bopd)
• Multiple pay zones
• Upside reservoirs○ Thin beds below resolution of wireline logs○ Weathered basement / ‘granite wash’
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 13
Lake Albert Rift Basin Lacustrine Shale Seals
SEAL
SEAL
SEAL
SEAL
Laterally extensive shalesdeposited in lakes provide
top seals to reservoirs
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 14
Trap Types in Lake Albert Rift basin
• Structural folds and noses trapped against rift boundary faults
○ Proved by Waraga / Mputa / Kingfisher –sealed against basement – de-risked
○ Present all along basin bounding faults
• Upthrown and Downthrown fault traps
• Upside play in fractured / weathered basement (yet to be successfully flow tested)
Sandstone (reservoir)
Shale (source rock / seal)
Basement (seal) Oil Gas
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 15
Trap Types in Lake Albert Rift basin
• Channel sand stratigraphic traps in buried valleys incised into basement
• Demonstrated at Mputa 2
• Kaiso Tonya 3D will show distribution of these incised valleys and channel sands
Sandstone (reservoir)
Shale (source rock / seal)
Basement (seal) Oil Gas
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 16
Trap Types in Lake Albert Rift basin
• Nearshore material traps associated with major basin faults
• Basin noses trapped against basement
• Submarine fans & stratigraphic traps
• Shallow simple folds offshore, some with amplitude anomalies
• Tilted fault blocks and horsts below the lake and in Butiaba-Paraa
Sandstone (reservoir)
Shale (source rock / seal)
Basement (seal) Oil Gas
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 17
Trap Types in Lake Albert Rift basin
Sandstone (reservoir)
Shale (source rock / seal)
Basement (seal) Oil Gas
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 18
Uganda PEPD Vision
• Over some 20 years visionary Ugandan leaders and geologists recognised the oil potential of the Lake Albert Rift Basin
• Foresight based on○ Fundamental surface geology○ Surveying and mapping○ Sampling of seeps○ Interpretation of Waki-1 (1938)○ Analogue basins
• Young earth scientists developed in Uganda and at Universities overseas
• Consequence of vision and affirmative early plans and actions means the PEPD is a very capable technical partner
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 19
Tullow/Energy Africa : Uganda activity and investment history
Farm in Block 3
Farm in Block 2
2D acquiredOver Block 3
2D acquiredOver
Lake Albert
Turaco-1 Drilled
Turaco-2 DrilledGas discovery
2D acquiredOver
Kasio-Tonya
3D survey acquired
Over Turaco
Turaco-3 Drilled
Co2 discovery
2D acquiredOver
Kingfisher
Block 1 signed
Mputa-1 Drilled
Oil discovery
Mputa-2 Drilled
Oil discovery
Nzizi-1 Drilled
Oil discovery
Kingfisher-1 Drilled
Oil discovery
Seismic campaign
Mputa-3 Drilled
Oil discovery
Mputa-4 Drilled
Oil discovery
Nzizi-2 DrilledOil discovery
NgassaDrilling
2001$3.4m
2002$3.4m
2003$5.5m
2004$17.0m
2005$11.1m
2006$44.6m
2007>$100m
Kingfisher-1 Tested
Seismic campaign
Blo
ck 3
Blo
ck 2
Blk
1
Waraga-1 Drilled
Oil discovery
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 20
INTERIM RESULTS - 06
Current Exploration Campaign
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 21
Basin-wide strategy• Leverage knowledge and influence• Swiftly test billion barrel basin potential• Scaled development options
Hardman deal• Increases influence and materiality• 100% and operatorship of Block 2
World-class basin potential• Eight wells : Eight successes• First oil & gas flow tested in Uganda• Highly productive reservoirs, 33º API
Challenges• Landlocked (1,300km from ocean)• Establish reserves threshold for export• Balancing long & short term goals
Uganda - Leading position in the Lake Albert Rift Basin
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 22
Lake Albert Rift
3D Seismic
Ngassa
Kaiso-Tonya Discoveries
Kingfisher
Onshore targets (2008-09) Oil seeps
Uganda DRC Alluvial Fan
Rift Scarp
Low sinuosity channels
Semiliki Delta
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 23
Uganda - Preparing for commerciality in Block 2 (100%)
Kaiso-Tonya area
• 3D seismic – expect complete end Nov 2007• Nzizi-2 & Mputa-3 drilled, Mputa-4 drilling• Early production sanction expected in Q4 2007• First oil targeted for 2009
Butiaba area
• 2D seismic near completion, structures identified• Light rig tender ongoing• 3+ exploration wells being prepared for 2008
Exploration of large lake structures
• Significantly de-risked by Kingfisher-1• Rig contracted to drill Ngassa-1 and Kingfisher-2• Ngassa-1 expected to spud in October 2007• Lake drilling solution for 2008 being evaluated
Block 2 – Ngassa & Lake• 3D seismic (Kaiso Tonya)• 1 Ngassa well (2007)• Lake survey & rig tender
Block 2 - Butiaba• 2D Seismic (2007)• 2-4 wells (2008)
Block 2 – Kaiso-Tonya• 3D (500km2) seismic• 3 onshore wells (2007)• Early Production System
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 24
Uganda – Extending success into Blocks 1 & 3A (50%)
Block 1
• Cooperation with Tullow operated seismic• 2D seismic ongoing, structures identified• Light rig tender ongoing• 1-2 exploration wells being prepared for 2008
Block 3A
• 3D seismic acquired over Kingfisher-1 discovery
• Processing started and 3D interpretation planned
• Kingfisher-2 expected to spud in Q1 2008• Pelican planned for H2 2008
Block 1• 2D Seismic (2007)• 1-2 wells (2008)
Block 3A• 3D/2D Seismic• Kingfisher-1 Well (2007)• Kingfisher-2 well (2008)
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 25
INTERIM RESULTS - 06
Building blocks for threshold export volume
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 26
Lake Albert Rift Basin Lead & Prospect Funnel
CurrentWave
(1H 08)
NextWave
(2H 08)
EmergingWave (09)
Drilling
Ngassa
MputaNziziKingfisherWaragaKaiso-T 3DKingFisher 3D4D Modelling
Butiaba-Paraa leads
Offshore leads
2D Seismic
Butiaba-Paraa
prospects
Waki-up-dip
Upsideplays
Offshore follow-up
DRC
2D Seismic
100-250 mmbo(pre-3D)
Appraisal
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 27
Building blocks for threshold export volume
• Kaiso Tonya (Waraga / MPuta / Nzizi)
• Butiaba-Paraa (another Kaiso-Tonya? Waki-up-dip / Songo)
• Nearshore material prospects (Kingfisher / Ngassa)
• Lake prospects (Pelican / Ntera)
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 28
Kaiso Tonya geological models – 200 MMbo upside potential
Increasing understanding through appraisal• Reservoir: distribution and quality• Net Pay: upside in thin beds and weathered
basement• Column Height: Definition of hydrocarbon
contacts• 3D expected to firm up models
Pre-appraisal model (35+ MMbo)• More isolated volumes
○ No alluvial fans○ Isolated channels○ Shoreline deposits
• More wells required to develop field
Possible alternative model (100+ MMbo)• More connected volumes
○ Alluvial fans○ Channels extend to lakeshore○ No shoreline deposits
• Wells in good communication
NziziMputa
NziziMputa
Pre-appraisal model
Possible alternative model
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 29
Building blocks for threshold export volume
• Kaiso Tonya (Waraga / MPuta / Nzizi)
• Butiaba-Paraa (another Kaiso-Tonya? Waki-up-dip / Songo)
• Nearshore material prospects (Kingfisher / Ngassa)
• Lake prospects (Pelican / Ntera)
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 30
• Residual gravity anomalies reveal several structures
• Structures have been confirmed by seismic data and will be tested by exploration drilling
• Compares well with Kaiso-Tonya and Sudan where major oil fields coincide with gravity highs
Residual gravity anomaly map of EA2, showing distribution of gravity highs oil seepages and well locations
Butiaba: gravity survey
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 31
Butiaba: further upside potential in Block 2
Building 2008 Programme
• Waki-1 (1938)○ Up-dip potential
• Block-1 & 2 Synergies○ Coordinated seismic & drilling○ Rig tender closing
• Onshore & Nearshore○ Accessible prospects○ Benign terrain
Block 2Infill Seismic
Planned
Block 22D Seismic
Acquired in 2007
Another Kaiso-Tonya? Tullow Interest – 100%Another Kaiso-Tonya? Tullow Interest – 100%
Seismic cross sections
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 32
Butiaba: Waki up-dip
SW
TD at 1232m in basement 2km
WakiWaki-2
Amplitude anomaly
Waki-2 >300m vertically up dip
1173m Sand found with oil –no test
NE
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 33
SW NE
Butiaba: Multiple structural traps along basin boundary fault
0.5
1.0
1.5
Waki-18
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 34
Building blocks for threshold export volume
• Kaiso Tonya (Waraga / MPuta / Nzizi)
• Butiaba-Paraa (another Kaiso-Tonya? Waki-up-dip / Songo)
• Nearshore material prospects (Kingfisher / Ngassa)
• Lake prospects (Pelican / Ntera)
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 35
High Impact Lake Prospects: Kingfisher & Ngassa
2007 – 2008 Nearshore Programme
• Nabors 221 Rig
○ On-site for October spud○ Ngassa-1 90 day well○ Contingent testing
• Ngassa risk reduction
○ Nzizi-2 gas○ Mputa-3 sands○ Kingfisher reservoirs / seals
• First step towards realizing potential of Lake Albert prospects
○ Lake-bed coring initiated for rig tendering
○ Drilling H2 2008
Well Trajectory
MidSecondaryObjectives
DeepPrimary
Objectives
ShallowSecondaryObjectives
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 36
Kingfisher Discovery, Lake Albert Rift
Top Kisegi
M’Puta EQ
Top Kakara
Top Oluka
Top Nyabusosi
Top Nyaburogo
KF-1
Base Kakara
Base Miocene
KF-1ST
Secondaryobjective
Primary objective
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 37
TD 1- 3600mSRD
N’Gassa-1 wellProjectedSP 2417
Penetrates highamplitude section
Good shallow closurePossible oil shows
Penetrates the primary target
Penetrates Secondary target
20”
13 3/8”
9 5/8”
7”
90
450
700
300
1km
EXPECTED LITHOLOGIES
Ngassa-A Well – Spud October 2007
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 38
Building blocks for threshold export volume
• Kaiso Tonya (Waraga / MPuta / Nzizi)
• Butiaba-Paraa (another Kaiso-Tonya? Waki-up-dip / Songo)
• Nearshore material prospects (Kingfisher / Ngassa)
• Lake prospects (Pelican / Ntera)
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 39
Ngassa – Nose extends from nearshore to offshore
Seismic Line
shown next
Ngassa – follow-on target – amplitude supported
Ngassa nose currently being drilled
Ngassa downthrownPlay (Kingfisher
analogue)
HLA0
3-00
6
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 40
Ngassa– follow on potential offshore
Amplitude support for presence of hydrocarbons in Lake Albert
Common Amplitude Termination (‘CAT’)
Additional amplitude with CAT
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 41
Closure at multiple
stratigraphichorizons
Ntera West
Ntera East
Ntera offshore prospect Block 2
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 42
INTERIM RESULTS - 06
Exploration Summary
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 43
Strategy
• Establish working petroleum system in frontier basin and at low cost○ Integrate a minimal set of gravity, geological and 2D seismic surveys○ Drill shallow wells at Waraga and MPuta
• Extend lead inventory through modern gravity and 2D sesimic surveys
• Map and mature leads into prospects and procure appropriate rigs
• Drill out prospect inventory to establish pipeline threshold volumes
• Appraise discoveries through 3D seismic and appraisal drilling
• High resolution subsurface modelling
• Early production system and reservoir connectivity testing
SlideTullow Oil plc – Uganda Analyst Visit – October 2007 44
Resource volumes
• Current assessment of basin volumes discovered: 100-250 mmbo
• Building blocks have potential to reach pipeline threshold volume○ Kaiso Tonya (Waraga / MPuta / Nzizi)
○ Alternative geological model 100 mmbo (200 mmbo P10 including speculative upside plays)
○ Butiaba-Paraa (Waki-up-dip / Songo)○ Another Kaiso-Tonya?
○ Nearshore material prospects (Kingfisher / Ngassa)○ Each multi-100s mmbo prospects
○ Lake prospects (Pelican / Ntera)
○ Currently 25 undrilled leads and prospects
• Basin has billion barrel potential – 80% unexplored