21/29c Relinquishment Document

Transcription

1 /9c Relinquishment Document ) icence information icence : P.5 lock(s) : /9c South West ocation : Western Platform, CNS Operator : EnCore Petroleum (5.6%) Co-venturers : Petro-Canada (5.00%) Nexen (8.98%) Maersk (.%) Date Award /ic Rd : 6/03/97, Round Expiry Date : 5/03/08 Area : 5. sq km Work Commitment : Fulfilled Seismic Surveys : Quad Western 997 Wells Spud TD Fm Result /9b- 978 Cretaceous P&A dry hole /9b- 98 Zechstein P&A oil shows lock(s) : /9c South East Operator : EnCore Petroleum (6.3%) Co-venturers : Nexen (8.98%) Maersk (.7%) PetroCanada (5.00%) Date Award /ic Rd : 6/03/97, Round Expiry Date : 5/03/08 Area : 30 sq km Work Commitment : Fulfilled Seismic Surveys : Quad Western Geophysical 997 reprocessed for Shell 998 Wells Spud TD Fm Result /9b- 98 Zechstein P&A oil well /9b-9 99 Palaeocene P&A oil well ) Exploration activity Seismic purchase, reprocessing and rock physics work The Group purchased the WesternGeco spec survey covering /9b and two Shell proprietary surveys covering adjacent block /30S. A total of 6 sq km of data was reprocessed in 006/007 (Kirchoff PSTM) with deliverables including:. Full Offset Stack. MR volumes 3. Gathers. Extensive rock physics modelling of the Tay and Forties sand systems was undertaken. The key conclusions were: The seismic response from the Tay sandstone shows a class 3 AVO response when oil or gas replace brine; the response strengthens with increasing thickness and HC saturation of the oil or gas column A brine filled sand would be invisible on the seismic data at depths of 5800 ft /9c Relinquishment Document Page of 7 October 007

2 Oil filled sands should look similar to gas filled sands on the crossplot There should be clear discrimination of hydrocarbon zones provided the zone is of sufficient thickness The reprocessed data outline is illustrated below. b 7 FYNE " 8Z 6 & D DANDY 5 3 GUIEMOT WEST " 5 3 /9b GUIEMOT A 9 GANNET E 6 9 GANNET C O 7ZST, O O 9A 6A GANNET F 3*,3ST O"O 5 & 7 8 8/b /30S 8/5a 9/a A O 9/b 8/a 8/5b 3) Prospectivity Analysis Two discoveries within the Tay Sandstone and one prospect within the Forties sand system have been evaluated on /9c. Forties Play Grasshopper Prospect A structurally robust four-way dip closure with stratigraphic trapping upside is identified within the Forties sand system updip and to the southwest of the Gannet E Field. The structure has a crest of 50 ft with a most likely closing contour of 5390 ft. Additional stratigraphic closure could extend the closing contour to 50 ft. The structure is updip of Wells /9b- and /9b- where excellent quality Forties sands were encountered. Conclusions from the AVO evaluation were: Paleocene Gannet E has a weaker AVO signature that is not restricted to the -way dip closure. The weaker response is probably due to the drop in API and GOR from 36 and 00 down to and 88, respectively. Grasshopper has a weak AVO that is not confined to closure. The zone here is 00ft shallower and probably lower API and GOR /9c Relinquishment Document Page of 7 October 007

3 Grasshopper (F) -way dip closure at Top Forties Sst Grasshopper Upside Stratigraphic closure of Forties Sst 0 3km Top Forties Sandstone Depth Structure Map SW Grasshopper /9b- NE Top Forties alder Chalk Seismic ine across Grasshopper Grasshopper Spill point of Stratigraphic closure of Forties Sandstone at 50 ft Grasshopper Prospect - way dip Minimum Most ikely Maximum Upper Forties only Crest ft Closing Contour ft Hydrocarbon column ft Gross Reservoir Thickness ft Gross Rock Volume acreft,686,686,686 Net:Gross % Porosity % Sh % FVF bbl/stb..5. Rec Factor Oil % STOIIP Total MMO Structural Closure 5390ft Minimum Case Stratigraphic Closure 50 ft Maximum Case Stratigraphic Closure 50 ft Grasshopper Deterministic Volumetrics Reserves Total MMO Grasshopper Prospect - Strat Minimum Maximum Upper Forties only Crest ft Closing Contour ft Hydrocarbon Column ft Gross Reservoir Thickness ft Gross Rock Volume acreft,9 7,80 Net:Gross % Porosity % 8 8 Sh % FVF bbl/stb.5.5 Rec Factor Oil % STOIIP Total MMO Reserves Total 5.0. MMO /9c Relinquishment Document Page 3 of 7 October 007

4 Well /9b- CPI Tay Play Crabtree Discovery The Crabtree discovery was made by Well /9b-9 which encountered a hydrocarbon column with an OWC at 576 ft within Tay Formation sands. 7 deg. API was recovered from RFT, no DST was conducted. There is no obvious closing mechanism to this discovery and it is assumed that the trapping mechanism is stratigraphic. The outline of the discovery is potentially defined by the amplitude response within the Tay interval. AVO modelling of these amplitudes indicate that they are mostly increases in acoustic impedance and may represent reservoir presence and not necessarily a hydrocarbon indicator. /9b-9 Crabtree Amplitude Outline Top alder Depth Structure 0 km /9c Relinquishment Document Page of 7 October 007

5 Tricia Crabtree 0 km Tay Formation Amplitude Extraction OJECTIVE:TO TEST STRATIGRAPHIC EXTENSION OF /30- ACCUMUATION TO THE WEST INTO OCK /9. RESUT:8 FEET OF OIEARING SAND AT TOP TAY; RECOVERED 7 o API OI AVERAGE HC SAT. 7%; AVERAGE POROSITY 3%; CEAR OWC AT 5837 (576 SS) EST GOC 5738 (5665 SS) RESIDUA HC SATURATIONS (30%) FROM WE NOT TESTED Gross Interval Net Sand 36 ft net 69 ft net Well /9b-9 CPI SW /9b- /9b-9 NE Tay alder Chalk Seismic ine across Crabtree /9c Relinquishment Document Page 5 of 7 October 007

6 Crabtree Discovery Minimum Most ikely Maximum Edge of Tay Sst Fairway Closing Contour ft Areal Closure acres 9 9,069 Gross Reservoir Thickness ft Gross Rock Volume acreft 783 7,78 8,05 Net:Gross % Porosity % Sh % FVF bbl/stb..5. Rec Factor Oil % STOIIP Total MMO Reserves Total MMO alder to Tay Amplitude. alder Depth Structure Crabtree Deterministic Volumetrics Tricia Discovery The Tricia discovery was made by Well /9b- which encountered a hydrocarbon column within Tay Formation sands. deg. API was recovered from RFT, no DST was conducted. RFT pressure data indicates a potential OWC at 580 ft TVDSS. There is no obvious closing mechanism to this discovery and it is assumed that the trapping mechanism is stratigraphic. The outline of the discovery is potentially defined by the amplitude response within the Tay interval. AVO modelling of these amplitudes indicate that they are mostly increases in acoustic impedance and may represent reservoir presence and not necessarily a hydrocarbon indicator. Edge of Tay Sst Fairway Top alder Depth Structure 0 km /9c Relinquishment Document Page 6 of 7 October 007

7 icence : P. 5 lock(s) : Well /9b- CPI Tricia Discovery Minimum Most ikely Maximum Closing Contour ft Areal Closure acres ,00 Net Reservoir Thickness ft Gross Rock Volume acreft 89 7,875 36,70 Net:Gross % Porosity % Sh % FVF bbl/stb..5. Rec Factor Oil % STOIIP Total MMO Reserves Total MMO Tricia Deterministic Volumetrics /9c Relinquishment Document Page 7 of 7 October 007