EXPLORATION. Johan Sverdrup Discovery. Classification: Internal

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1 EXPLORATION Johan Sverdrup Discovery Classification: Internal

2 Exploration What is exploration? Scale Perspective What type of data do we use? Basic exploration geology What makes a successful prospect? Prospect and Play Analysis Evaluating Volume and risk prognosis Statoil Exploration process Classification: Internal Classification: Classification: Internal Internal

3 Exploration Visualising and testing the subsurface Geology and geophysics Creativity Big scale operations, seismic and drilling Business process Commercial Valuation Risk Assessment Contracts and negotiations Element of luck?

4 Global basin play - prospect reservoir 100 s km 5 km Classification: Internal Status: Draft

5 DATA Gravity Data Field or outcrop data Satellite Data Aerial Surveys i.e Gravity / Magnetics / Bathymetry / Electromagnetics Field work Modern analogues 3D Seismic & bathymetry data Seismic Data - $$$$ 3D Seismic Depth Imaging Well Data - $$$$ Well Data - Wireline Logs Seismic and Well Data Classification: Internal Status: Draft

6 New perspectives Changed assumptions Observation/Event Photo: Marco Fulle

7 Datasets : Seismic Acquisition On land At Sea Vibroseis Air Guns Classification: Internal Status: Draft

8 2D Seismic Acquisition P = Pressure waves S = Shear waves Source Single streamer with hydrophones Survey lines often kms apart Seismic section Classification: Internal Status: Draft

9 2D Seismic Acquisition Regional basin scale surveys. -5 to 20 km line spacing, -50 to 200plus km lines -Used to: -Interpret structural trends -Basin modelling Semi regional block wide surveys -1 to 4 km line spacing -5 to 50 km lines -Used for: Text -Mapping prospective structures Classification: Internal Status: Draft

10 2D regional seismic line across the North Sea sedimentary basin 10 km TGS-NOPEC Millennium Atlas Classification: Internal Classification: Classification: Internal Internal Ahmadi et. al 2003

11 2D Seismic Acquisition Geoseismic Section Classification: Internal Status: Draft

12 3D Seismic Acquisition Close spacing between streamers (10s m apart) allowing data to be represented as seismic cubes Principle of 3D acquisition Seismic cube Classification: Internal Status: Draft

13 3D Seismic Acquisition Flat Spot - Interface between Oil and water Regional mapping & play analysis (prospect generation) Seismic & geological interpretation at prospect level, ending up in volume & risk analysis (prospect evaluation) G a s s O l j e Helps to understand complex geology Classification: Internal Status: Draft

14 BASIC PRINCIPLES OF EXPLORATION GEOLOGY What are the main ingredients for a successful prospect? SOURCE RESERVOIR SEAL TRAP STRUCTURA L SPILL-POINT Classification: Internal Status: Draft

15 Index Source Presence of oil seeps at surface may be a good indication that there is an active petroleum system in the subsurface Classification: Internal

16 Stratigraphy - History of depositional environments Youngest Oldest Stuart Heggie Classification: Internal Classification: Classification: Internal Internal

17 SOURCE ROCKS - Decaying organic matter (terrestrial vegetation, plankton, algae, bacteria... ) Helge Løseth Classification: Internal

18 SOURCE ROCK What is it? Organic matter and clay / rock fragments Maturation Migration Charge Preservation What do we need to know? Depositional setting Type of organic material Depth of burial / age Temperature gradient in area Composition of rock, Total Organic Carbon content Classification: Internal Status: Draft

19 Kerogen types 23 - Classification: Internal

20 Maturation of organic material Kerogen types 24 - Classification: Internal

21 RESERVOIR ROCKS - Porous Rocks (sandstones, limestones) Sandstone Classification: Internal Classification: Classification: Internal Internal

22 RESERVOIR Types of reservoirs Clastic - Aolian, Marine, Fluvial, Lacustrine etc Carbonate Depositional Setting Geometry Distribution Quality Processes that control erosion and deposition Chemical, Glacial, Wind, Rivers, Waves, Tides, Gravity In exploration we need to calculate where the reservoir was in the past by using what we see today... Classification: Internal Status: Draft

23 CLASTIC RESERVOIRS : Aolian Sandstones Classification: Internal Classification: Classification: Internal Internal

24 CLASTIC RESERVOIRS : Alluvial fans and deltas Classification: Internal Classification: Classification: Internal Internal

25 CLASTIC RESERVOIRS : Fluvial (river) Sandstones Classification: Internal Classification: Classification: Internal Internal

26 CARBONATE RESERVOIRS : Corals, reefs and shell debris are main components in carbonate reservoir rocks Classification: Internal Classification: Classification: Internal Internal

27 RESERVOIRS : From outcrop to model From seismic data Classification: Internal Classification: Classification: Internal Internal

28 Reservoir Properties (Clastics) Oil and gas in pore space between sand grains Porosity = Volume of pore space Volume of rock Porosity decreases with increasing burial depth Temperature most important factor. Porosity drops off dramatically when temperature reaches C Quartz overgrowth SiO 2 Snøhvit, at 2401m. Pure sandstone. Mostly quartz grains little quartz overgrowths. Grain size ca 0.25mm. Porosity ca 20% Permeability ca 700mD. Pore space Classification: Internal Classification: Classification: Internal Internal

29 SEAL : Impermeable rock (i.e Shale, Mudstones, salt) Sands tone Mud, Shale Sandstone Sandstone Decaying Org.matter Classification: Internal Classification: Classification: Internal Internal

30 TRAP - Geological features that focus and trap hydrocarbons under the seal Helge Løseth Classification: Internal Classification: Classification: Internal Internal

31 TRAP TYPES ANTICLINAL TRAPS SALT DIAPIR TRAPS Plan view FAULT TRAPS

32 Classification: Internal Classification: Internal TRAP TYPES

33 TRAP TYPES SEISMIC SECTIONS Classification: Internal Status: Draft

34 PROSPECT ANALYSIS : Volumetric Input data Area Hydrocarbon saturation Degree of fill, S hc Depth Oil shrinkage / Reservoirthickness Formation volume factor Gross rock volume Net to Gross Porosity Gas-oil-ratio GRV x N/G x Phi Results x Shc x 1/Fvf x RF = Recoverable oil/gas Gross Rock Volume x Net to gross x porosity x hydrocarbon saturations x formation volume factor x recovery factor Classification: Internal Classification: Internal

35 Basin, play and prospect interrelationship Reservoir Source Seal Classification: Internal

36 PLAY RISK : Critical Risk Maps (Traffic Light Maps) SEAL RESERVOIR SOURCE Individual Components : Seal Reservoir Source Green area: Favourable Yellow area: uncertain Red area: Unfavourable Classification: Internal Classification: Internal

37 PLAY RISK : Critical Risk Maps (Traffic Light Maps) Reservoir + Source = + Seal Green area: Favourable Yellow area: uncertain Red area: Unfavourable Classification: Internal Classification: Internal

38 P(Prospect) P(Play) PROSPECT ANALYSIS : Risking Probability Evaluation Example : P(Reservoir) P(res) = 0,7 P(Seal) P(seal) = 0,9 P(play) = 0,38 Chance for a working P(Source) P(source)= 0,6 play (somewhere) P(Reservoir) P(Trap) P(res) = 0,9 P(trap) = 0,6 P(prospect) = 0,43 Chance for a prospect success P(Source) P(source/charge)=0,8 Given that the play works P(Discovery) P(discovery) = 0,16 Classification: Internal Classification: Classification: Internal Internal

39 Probability PROSPECT ANALYSIS : Volumetric output from Montecarlo simulation Minimum Most likely Maximum (Parameters) P90 Probability Distribution Mean P10 Monte Carlo simulate in GeoX Min Ma P90 Mean P10 (risked and unrisked) Volume (million barrels oil) Classification: Internal Classification: Classification: Internal Internal

40 Technical & economical evaluation Exploration / development drilling Drilling costs Geological/geophysical evaluation Volumes & probabilities EXPECTED NET PRESENT VALUE KPI s Sensitivity analysis Reservoir evaluation Recoverable resources Reservoir quality Production profile No. of wells Facilities design Cost estimation Schedule Transport solution Economic assumptions Price Inflation & exchange rate Taxation Discount rate Tariffs Classification: Internal Classification: Internal

41 THE EXPLORATION VALUE CHAIN Requirements for DGA: Approval to develop a business opportunity Requirements for DGB: Approval to negotiate Requirements for DGC: Decision to access a new exploration opportunity Requirements for APx: Approval to initiate well planning Requirements for APy: Approval to commit to drilling a well Requirements for APz: Approval to start appraisal of a discovery Requirements for DG0: Approval to enter the feasibility phase Classification: Internal

42 Ideas - Creativity Basin evaluation DGA THE EXPLORATION FUNNEL DGB/C DG0 Bid round evaluation Basin 1 New Venture Group Licence evaluation Prospect maturation Prospect drilling Discoveries Basin 2 New Venture Group Discoveries maturing to DG0 Basin 3 New Venture Group Regional Group Basin 4 Basin ranking New plays Yet-to-Find Basin portfolio Concession Round NVG Seismic interpretation Basin evaluation & assessment YtF Petroleum system Play evaluation Prospect generation Value assessment Prospect Generation Prospect Evaluation Seismic interpretation Seismic Acquisition/ Reprocessing LFP, EM Value assessment Well- & geo-operations Formation evaluation Seismic calibration Volume assessment Appraisal planning Well- & geo-operations Formation evaluation Seismic calibration Volume assessment Value assessment $ Details $$$ Classification: Internal Classification: Classification: Internal Internal

43 Process in a license round Invitation/announcement Pre-qualification Preparation, data acquisition, evaluation Establishment of partnerships Priority, recommendation for bidding Application, documentation, bid Announcement of bidding results License negotiations Award, work programme, start-up Partnership agreements Success or failure; development/production/abandonment or relinquishment Classification: Classification: Internal Internal

44 Summary: Tasks in Exploration Regional mapping Play analysis Prospect mapping Seismic Interpretation Log analysis/petrophysics

45 Summary: Tasks in Exploration Volume and risk analysis (prospect evaluation) Well planning, follow up Post well assessment Appraisal of discovery G a s s O l j e

46 Ultimate aim : Exploration Success! Sand with oil Sand with water Classification: Internal Status: Draft

47 Unconventional Hydrocarbons The development and application of new technology led to commercially access hydrocarbons previously thought of as unproducible Now evaluating more opportunities, mainly in the USA but also globally Early entry, inexpensive land acquisition Upside potential from applying modern and new technology Gas Hydrates CBM Tight reservoirs Heavy oil Tar sand Oil shale Shale oil Basin centred gas Shale gas 73 - Classification: Internal

48 Thank you 74 - Classification: Internal