Relinquishment Report
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Relinquishment Report for Licence P194 (9/5a), P404 (9/10a) and P118 (10/1a) Estimates, statistics, opinions and forecasts contained in this document are based on TOTAL’s own information and knowledge. They are provided in good faith, but, by their nature, are based on a number of assumptions and are subjective. Readers should therefore carry out appropriate reviews and due diligence to satisfy themselves as to all information contained in this document including, without limitation, TOTAL’s opinions, prospect evaluations, reserve figures, production and cost forecasts and all technical aspects of production, transmission and other facilities. While this information was prepared in good faith, no representation or warranty, expressed or implied, is or will be made, and no responsibility or liability is or will be accepted by TOTAL or any of their respective affiliates or subsidiaries, employees, officers, directors and agents as to, or in relation to, the accuracy or completeness of this document and any liability thereof is hereby expressly disclaimed. In furnishing this Relinquishment Report to DECC, TOTAL undertakes no obligation to provide any Third party recipient with access to any additional information. 1 Contents 1. Licence Information ........................................................................................................................ 3 2. Licence Synopsis .............................................................................................................................. 3 3. Work Programme Summary ........................................................................................................... 4 4. Database ......................................................................................................................................... 4 5. Prospectivity.................................................................................................................................... 5 6. Further technical work undertaken ................................................................................................ 7 7. Resource and Risk Summary ........................................................................................................... 7 8. Conclusions: remaining prospectivity ............................................................................................. 8 9. Clearance ........................................................................................................................................ 8 Figure 1. P194, P404 and P118 licenses and Seismic database .............................................................. 4 Figure 3. Balder Lobe Lead Seismic Section ............................................................................................ 5 Figure 4. Balder Lobe Lead Depth Map ................................................................................................... 6 Figure 5. Regional Stratigraphic Chart .................................................................................................... 6 Figure 6. 9/5a-3 Balder feeder channel .................................................................................................. 7 2 1. LICENCE INFORMATION Licence Number: P194, P404 and P118 Licence Round: 3rd Round licence Licence Type: Traditional Block Numbers: 9/5a, 9/10a and 10/1a Total E&P UK Ltd confirms DECC is free to publish this report and that all third party ownership rights have been considered and appropriately cleared for publication purposes. 2. LICENCE SYNOPSIS Blocks 9/5a, 9/10a and 10/1a contain the UK part of the Frigg Field (Fig.1), which was unitised in 1976 under the Frigg Field Unitisation Treaty and the Frigg Field Agreement between the governments of the UK and Norway. TEP Norge was designated field operator. Frigg was discovered in 1971 and development approval received in 1974. A column height of 160m of dry gas lying over a 9m thick oil rim was calibrated in the sandy turbiditic reservoirs of the Frigg formation, Lower Eocene in age. IGIP are estimated around 247 Billion std.m3. A total of 191.7 Billion std.m3 was produced between Sept. 1977 and Aug. 2004, date of the final shutdown. DECC has requested TEPUK to relinquish 9/5a (P194), 9/10a (P404) and 10/1a blocks (P118) as the Frigg field ceased production more than 5 years ago (as per UKCS DECC rules. Block 10/1 was first awarded in June 1970 in 3rd Round to a Total operated group and partially relinquished in January 2006 to create block 10/1a. Block 9/10 was first awarded in November 1965 in 2nd Round to a Total operated group as part of licence P090, then split in 1971 into 9/10a and 9/10b. Block 9/10a (including Frigg Unit) was given a different licence number (P404) in December 2004 and part of it was relinquished in December 2007. Finally, Total/Elf acquired Frigg Unit interest in the 9/5 block in July 1993. Block 9/5aN part was totally relinquished in March 2004 and the Block 9/5aS was relinquished in March 2008 leaving just the current block 9/5a as licensed acreage. 3 Figure 1. P194, P404 and P118 licenses and Seismic database 3. WORK PROGRAMME SUMMARY All original work programmes completed. 4. DATABASE TEPUK has full 3D seismic coverage across the P194, P404 and P118 licenses. Figure 1 shows a map of the seismic database used. The well results on the P194, P404 and P118 licences and on previous licenses are summarised in the table below: Well Operator Spudded Completed TD (m) Results Comments Primary objective Lower Eocene Frigg Sands already proven in the 10/1a-1 & 31/12/71 (1) 08/02/72 (1) 900 (1) P/A Gas & Norwegian side and known to extend into the UK area. 1 Well P/A for Total Oil Marine 1A 27/02/72 (1A) 06/05/72 (1A) 2846 (1A) Oil operational problems. 92m gross reservoir with a full gas column (N/G 88%, 95% SG) & 11m of oil (N/G 100%) 10/1a-2 Total Oil Marine 09/05/72 24/06/72 2500 P/A Dry Objective was to verify presence of gas bearing Frigg Sands. Minor gas shows up to 3.8% C1 in the 40m net Frigg sands P/A Gas & 10/1a-3 Total Oil Marine 18/09/75 16/11/75 2760 Appraisal well to define extension and quality of Frigg Field western flank. Oil Very shaly reservoir with 14m of Net gas pay. Average SW 90% P/A Gas & Appraisal well to define extension and quality of Frigg Field western flank. 10/1a-4 ELF 21/11/75 10/01/76 2650 Gross sand is 235m with a Net of 170m. Net gas pay 114m with a SG 90% Oil and Net oil pay of 94m with a SO 82% 10/1a-5 & 05/12/84 (5) 10/01/85 (5) 1590 (5) P/A Gas & Appraisal well to define HC contact in the Frigg Field south-western flank. ELF Initial well (5) got stuck at 1438m and was P/A. Gross of 104m Gas bearing 5Z 11/01/85 (5Z) 08/03/85 (5Z) 2870 (5Z) Oil sands with a GS 89%. 23m Oil column with a SO of 49% 4 5. PROSPECTIVITY Balder Lobe Lead The Balder lobe lead is located just West of the main Frigg field (Figs. 2 and 3) and corresponds to the Eocene Balder stratigraphic unit (Fig. 4). 9/5a-3 well encountered 8m oil leg column at the Balder (Forties sand) interval (Fig. 5). It corresponds to a small 4 way-dip closure, upstream in the feeder channel of the Balder lobe. At the 9/5a-3 well location, Frigg channel and lobes do not interact with deeper Balder interval (Fig.5). Wells 10/1-2 and 10/1-3 have penetrated the Balder lobe water bearing (Fig.3). At this location, the Balder lobe 4 way-dip closure straddling blocks 9/5 and 10/1a (P118) seems to be in direct communication with the Frigg interval, as illustrated on the seismic section in Figure 2. The Seal risk was therefore identified as critical for the Balder lobe (Pseal = 20%). C.I. = 20m A Frigg Field A A’ A’ NW SE Top Balder Structural Depth map Balder Lobe Lead Frigg Field Flat Spot Top Frigg Communication? Top Balder Channel Top Cretaceous Figure 2. Balder Lobe Lead Seismic Section 5 Balder Depth map (C.I.: 10m) Petroleum Frigg Field results at Dry well Balder HC well Interval 10/1a-3 10/1a-2 10/1a-4 10/1a-5Z 9/5a-3 Balder lead 4WD Closure Area = 5.94 km2 Volume = 75 Mm3 Crest = 1982 m Spill Point = 2038 m 10/1a-1a HC Column = 56 m Figure 3. Balder Lobe Lead Depth Map Figure 4. Regional Stratigraphic Chart 6 Structural Depth map Top Balder Well 9/5a-3 C.I. = 20m GR Res DT 26Round Commit. Shoot 3D,DoD Balder lobe 9/5b Nexen 13km2, Potential Balder / Tuff 60m HC column Crest :1960m Lobe shape at Top Balder B Frigg Field 9/5a-3 Frigg Field 10/1-3 9/5a-3 B’ 10/1-2 Balder/Forties reservoir Fms more than 90m Gross sand thickness identified at well NW 9/5a-3 SE location B B’ Log results shown a 8m Oil leg (2128-2136) at the top of the Forties Fm, 1 segregated down-dip wells light oil & mud filtrate sample was taken controlling contact Structural depth map showing Frigg field & and a large lobe shape at TopBalder Balder. Well penetrations located within the main feeder channel Frigg Feeder Feeder and in the South East flank of the lobe shape Channel Channel Figure 5. 9/5a-3 Balder feeder channel No additional prospectivity was identified deeper than the Eocene stratigraphic interval. 6. FURTHER TECHNICAL WORK UNDERTAKEN In order to de-risk the seal parameter, an AVO cube has been generated over the area. Unfortunately, no AVO anomalies have been identified at the Balder lobe location. 7. RESOURCE AND RISK SUMMARY Resources Mboe Stratigraphic Net Risked Mean Level Min Mode Max Mean PS Resources Balder Lead Eocene 14.5 20 83.4 31 13% 2.9 Mboe The overall POS of Balder Lobe Lead has been calculated at 13% (1*1*.9*.7*.2) with Unrisked Mean oil Resources of 31 MMboe. The main risk is the lateral seal with a PS of