A Rotliegendes opportunity missed? May 2016
Licence details (Block 49/19b) Block: 49/19b Licence: P.1914 awarded in 26 th Round, 4 year term Effective date: 01/02/12, extended to end Dec 2017 Equity: SR (100%) Reservoir: Facies: Permian Rotliegendes aeolian sandstone Licence: Firm Commitment: Reprocess 300km 2 of 3D seismic data to PSDM (completed) & drill a well on Niadar to 2900m to the Leman Sandstone Page 1
Quad 48 & 49 Fields and Infrastructure Page 2
Overview Sterling Plans 3D seismic reprocessing of prospect completed in 2013 Well planning Bottom hole location identified On exploration success seek expedient route to development Feasibility study on development scenarios via nearby infra-structure completed Positive economics based on current price deck Page 3
Regional Top Leman Sandstone (Depth), Prospect, Leads and Fields Niadar Brigantine Depth (ft) Page 4
Regional Seismic Line W 49/18-5 E Tertiary Top Chalk Chalk BCU Triassic L.Cret. Top Zechstein Zechstein Nia Leman Sst.. Carboniferous Brigantine D Niadar Lead 2 Lead 6 Top Leman 4 km Depth (ft) Page 5
Niadar Top Leman Sandstone (Depth) Minimum contact 9100 ft? Niadar Prospect R3 Brigantine D R2 BR Platform Brigantine C CI 200 ft R1 Page 6
Depth (ft) Niadar Niadar Prospect Illustration X-Line 2745 SW NE R3 Top Leman Penetration 9197 ft TVDss Niadar Prospect Tie Line Intersection Top Zechstein 8800 ft 9000 ft Top Leman Base Permian PreSDM Depth Volume 1 km Page 7
Depth (ft) Niadar Tie Line to Illustrate the Leman Pick in the Upthrown Block NW Intersection with X-line 2745 SW Top Zechstein Imaging problems (over-migration) Top Leman Base Permian PreSDM Depth Volume 1 km Page 8
Well Depth (ft) TVDss Niadar PSDM Top Rotliegend Depth Prediction Error at Wells 10000 PSDM vs Actual Top Leman Sandstone Depth 49/13-2X 49/14a-2 9500 374 ft 9000 8500 8000 49/19-7 49/19-R1 49/19-1 49/19-3 49/19-5 49/19-6Y 49/19-R2 49/19-R3 (UT) 49/18-5z 49/18-2 Top Leman Depth TVDss Grid : Top Leman Depth PSDM Rev4 Well Grid depth (ft) Well depth (TVDss ft) Difference 49/13-2X 9946 9913-33 49/14a-2 9476 9737 261 49/18-2 8706 8750 44 49/18-5z 8880 8805-75 49/19-1 7919 7926 7 49/19-3 7850 7832-18 49/19-5 8098 7989-109 49/19-6 7513 7417-96 49/19-6Y 8216 8211-5 49/19-7 7839 7987 148 49/19-G1 7465 7402-63 49/19-G2 7315 7297-18 49/19-R1 7766 7936 170 49/19-R2 8413 8326-87 49/19-R3 (DT) 9267 9193-74 49/19-R3 (UT) 8819 9193 374 7500 7500 8000 8500 9000 9500 10000 PSDM Depth (ft) TVDss Exc. R3 (UT) Average 3 Standard Deviation 109 Page 9
Multi Layer Depth Conversion Workflow The following interpreted layers were used in the depth conversion 1. MSL to Seabed 2. Seabed to Base Tertiary 3. Base Tertiary to Base Chalk 4. Base Chalk to Top Zechstein 5. Top Zechstein to Base Zechstein In some realisations, the Zechstein was further divided into a hard layer (anhydrite, dolomite) and soft layer (salts). In this case, the hard-rock thickness was estimated by kriging thicknesses encountered in the wells. Work was undertaken by Earthworks using HIIP software Well data from R3 not provided or included Page 10
Impact on Niadar Area Depth X-Section (Xline 2745) Depth TVDss (ft) Niadar Prospect R3 (orthogonal to trajectory) Top Leman Penetration 9197 ft TVDss Uncorrected PreSDM (depth) Corrected PreSDM (depth) Earthworks Best Technical (not tied to R3) Alternative Earthworks Outcomes (not tied to R3) Page 11
Depth Conversion Summary All depth conversion methods suggest that the R3 Top Rotliegendes is more likely to have penetrated the downthrown side of the fault The multi-layer depth conversion methods are generally predicting shallower depths than the PreSDM depth volume, in the Niadar area Page 12
Niadar Petrel Modelling Brigantine development Niadar BTC Depth Structure Map R3 Page 13
Niadar Volumetrics (variable contact) Minimum Crest GWC Avg Phi 15% Avg Sw 35% 8375ft ss 9100ft ss FVF 240 IGIP 61bcf BTC Crest GWC Avg Phi 15% Avg Sw 25% 8375ft ss 9250ft ss FVF 240 IGIP 109bcf Max Crest GWC Avg Phi 15% Avg Sw 15% 8375ft ss 9600ft ss FVF 240 IGIP 227bcf Page 14
Niadar well planning and costs ($50,000 rig rate) Niadar Cost Summary Dry Hole Success Total ( mm) 8.7 (5.3) 5.14 13.8 Page 15