P1846 Relinquishment Report

Transcription

1 Document last updated :32 CEST

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3 1 Licence Information 1 2 Licence Synopsis 2 3 Work Program Seismic Reprocessing 4 4 Database Seismic Gravity and Magnetics 9 5 Prospectivity Update 11 6 Resource and Risk 12

4 List of figures 1.1 P1846 Location Map and Licence Details Completed FL008 3D Survey ST Reprocessed Seismic data coverage license P Comparison of original and reprocessed seismic data CV07-SRT mrg Statoil Seismic data (2D and 3D) coverage license P1847 prior to ST D and 3D seismic over P LCT96 Gravity and Magnetic Survey Outline used in Statoil regional studies

5 1 Licence Information Licence P1846 comprising blocks 212/30, 213/26c and 213/27c is one of a number of licences held by Statoil UK (P1846, P1847, P2067 and FL008) that lie adjacent to the UK and Faroe Islands boundary, immediately west of the Rosebank Field. Figure 1.1 outlines the key licence information regarding P1846 including a location map, summary time-line and work commitments agreed with DECC. Figure 1.1 P1846 Location Map and Licence Details Licence Information 1

6 2 Licence Synopsis P1846 was awarded in the 26 th UK licence round to Statoil (U.K.) Ltd, partners DONG Energy UK Ltd and OMV on the 10 th January 2011 under a traditional Seaward Production Licence. The agreed licence duration was 4 years and included a drill or drop decision which expired on the 10 th January The Licence terms included; Reprocessing 35km 2D seismic data (within UK blocks 212/30, 213/26c and 213/27c) Drill or drop commitment either; Drill 50m into the Palaeocene Lamba Formation or, Elect to allow the licence to automatically cease. Completed in addition to the firm work program; ca 18 km 2 of 3D data acquired as part of FL008 survey in Figure 2.1 shows the outline of the 3D survey and the coverage of license P1846. Figure 2.1 Completed FL008 3D Survey ST Completed in addition to the firm work program Licence Synopsis 2

7 Statoil's initial evaluation for the UK 26 th license round identified the possible extension of the Faroes FL008 Sula/Stelkur Lead into UK blocks 212/30, 213/16, 213/17, 213/21, 213/26c and 213/27c. The Sula/Stelkur lead was matured to prospect level under FL008 and was drilled in the summer of 2014, well 6104/25-1. All work commitments for P1846 have been met and a decision was made, with partner agreement, not to extend the licence beyond the initial four year term. Therefore the licence was left to naturally expire under the terms of the licence agreement on 10th January Licence Synopsis 3

8 3 Work Program 3.1 Seismic Reprocessing In December 2009 P1847 Partners agreed with the Faroes authorities to commit to an exploration well on the Súla-Stelkur Lead in licence FL008 by As part of the agreement 1,913 km of 2D seismic over blocks 212/30, 213/17, 213/21, 213/22' 213/26c and 213/27c were reprocessed to improve imaging of target intervals, lead size and to aid with well positioning. A total of 135km of 2D seismic data was reprocessed over P1847 (Figure 3.1). The seismic reprocessing used techniques developed by Statoil for sub-basalt imaging. Reprocessed seismic was received by Statoil UK in May License P1847 is covered by surveys CV (see section 4.1). Kirchhoff pre-stack time migration reprocessing was carried out on survey CV (License FL008) 2D data by Geokinetics Processing UK Limited during May to November Additional pre-stack depth migration test evaluation processing was performed during December 2010 to March 2011 on two test lines. The main objective of the reprocessing was to better image both post-basalt and intra-basalt targets and preserve amplitudes. At the end of the time reprocessing the 2D data were matched to a neighbouring L008 3D K-PSTM survey ST Figure 3.2 is a comparison of original and reprocessed data on line CV07-SRT Significant improvements in terms of noise removal, amplitude balancing and reflection coherency below 3300ms are observed in the reprocessed image. Intra-basalt reflectivity below c.3100ms has also been improved mapping of supra and intra basalt targets. Work Program 4

9 Figure 3.1 Reprocessed Seismic data coverage license P1847 Seismic Reprocessing 5

10 Figure 3.2 Comparison of original and reprocessed seismic data CV07-SRT mrg. See text for details Seismic Reprocessing 6

11 4 Database 4.1 Seismic The seismic data base for license P1846 is largely 2D data with the best data quality being the CV STR10 surveys which were reprocessed in and delivered as part of the work commitment. Statoil also has a number of other 3D surveys in the area; PGS Megamerge and Fugro Terracube, in addition to the proprietary FL008 survey ST12003 (Figure 4.1). The FL008 3D survey was acquired by PGS In 2013 over the Sula/Stelkur Prospect. Small extensions of the prospect extended into the UK licences P1846, P1847 and P2061 and are covered by the 3D as shown in Figure 4.2 Database 7

12 Figure 4.1 Statoil Seismic data (2D and 3D) coverage license P1847 prior to ST (license FL008 acquisition) in 2012 Seismic 8

13 Figure 4.2 2D and 3D seismic over P Gravity and Magnetics Statoil UK has a limited regional gravity and magnetic dataset, LCT96, covering a large swath of the Faroe Shetland Basin (Figure 4.3). The dataset was compiled, amalgamated and interpreted by LCT Ltd. on behalf of the Atlantic Margin Group (Enterprise Oil PLC, Mobil North Sea Ltd and Statoil) in The gravity and magnetic product is a merged and balanced grid of all provided surveys at a 1km grid spacing. Statoil, as part of a larger regional project, has evaluated this data to produce lineament interpretation using a USGS script applied to the 1st vertical derivative grids. This was used to locate grid extremes by using curvature analysis and produce a series of point-sets based on the maximum gravity/magnetic response which can be overlain on structural maps. Seismic 9

14 Figure 4.3 LCT96 Gravity and Magnetic Survey Outline used in Statoil regional studies Gravity and Magnetics 10

15 5 Prospectivity Update The well results for 6104/25-1 (Sula/Stelkur Prospect), drilled in 2014, were disappointing. To summarise, 6104/25-1 targeted two potential plays: The late Paleocene to early Eocene T45 Hildasay Fm which is the reservoir above the basalts in the Cambo Field The late Paleocene T40 Colsay Sandstone Member which is the reservoir within the basalts in the Rosebank Field The Stelkur target (Hildasay) encountered good reservoir quality sandstones but no shows were recorded. The Sula target (Colsay) found sediments but no reservoir and was thus also dry. Only in the success case at Sula/Stelkur would P1846 be prospective. As both targets were dry, no prospects are now seen in P1846. Prospectivity Update 11

16 6 Resource and Risk There are no prospects now mapped in P1846. Resource and Risk 12