RELINQUISHMENT REPORT LICENCE P.1966 UKCS BLOCKS 132/3, 132/4, 132/8, 132/9, 132/13, 132/14, 132/18, 132/19, 142/28 & 142/29

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1 RELINQUISHMENT REPORT LICENCE P.1966 UKCS BLOCKS 132/3, 132/4, 132/8, 132/9, 132/13, 132/14, 132/18, 132/19, 142/28 & 142/29 MARCH 2017 MARCH 2017

2 1 Licence Information Licence number: P 1966 Licence round: 27th Start date: 1 st January 2013 Licence type: Frontier Awarded area: km 2 Awarded Blocks 132/3,132/4, 132/8, 132/9, 132/13, 132/14, 132/18, 132/19, 142/28, 142/29 Partial relinquishment date: Effective 25 th Retained blocks: 132/3a, 132/8 & 132/13a December 2014 (75% relinquishment) Licence continued in Initial Term Retained area: km 2 Licence expiry date: 1 st January 2022 Working interests: Parkmead % & Operator P.1966 is located in the UKCS Atlantic Margin area, on the eastern shelf edge of the Rockall Basin, west of Scotland (Fig. 1). The 9-year frontier licence was awarded in 2013 to Parkmead (E&P) Limited (100%). 2 Licence Synopsis The initial P.1966 licence consisted of 10 blocks: 132/3, 4, 8, 9, 13, 14, 18, 19 and 142/28 & 29 totalling km 2 within the Rockall Basin to the west of Scotland (Figs. 1 & 2). The 27 th UKCS Licence Round application focussed on three stratigraphic leads; an amplitude anomaly at Eocene level, Godrevy, an amplitude anomaly of opposite polarity to Godrevy at Eocene level, named Longships (identified by DECC Promote 2012), and the Upper Cretaceous Bardsey amplitude anomaly (also DECC Promote 2012). Further leads were identified post-award at Oligocene, Eocene and Cretaceous levels. A partial relinquishment made in 2014 reduced the licence area by 75% to km 2 covering 3 (part) blocks (132/3a, 132/8 & 132/13a). The Bardsey lead (in block 132/18) was relinquished. The work programme post-award has been unable to mature any of the identified leads to drillable status and the licensee has therefore opted to relinquish P Work Programme Summary The commitment work programme consisted of the following: Obtain Seismic 2125 km 2 of 3D. A drill or drop well to 3350m TVDSS or 50m below the Top Balder, whichever is shallower. Full mapping of the 3D seismic dataset enabled an improvement in structural mapping and identification of seismic amplitude anomalies when compared to the original licence application work which was based solely on a short-term review of the 3D dataset. The data was of sufficient quality to address the geology of the blocks with regards to the structure, although interpretation beneath igneous units was limited. The seismic dataset was only available as full stack reflectivity and consequently amplitude anomalies could not be fully evaluated on gather or offset stack data (gathers had not been retained by the seismic contractor). Reprocessing from field tapes would have been of significant benefit to the licence but was not within the remit of the work programme. 4 Database At the time of licence award one 3D seismic survey was available covering the entirety of the P.1966 licence; the PGS MC3D PP983DXSRT survey. This remains the case at the time of relinquishment. At the time of application the seismic database consisted of 2D proprietary survey BP912D2001 (Fig.4) and a review of the PP983DXSRT survey was undertaken to allow for application of the blocks. To fulfil the licence work commitment, 2125 sq.km of PGS MC3D was obtained. Further 2D was obtained during the licence period, listed in Table 1, including the 2015 OGA Rockall 2D surveys (June 2016), 8 lines of which transect the three block P.1966 licence area with the line 78A033 tying the 132/06-1 and 132/15-1 wells across the 3D survey. 132/06-1 and 132/15-1 are the only wells in the UK sector within 150km of the licence. Six wells exist in the Irish sector within 100km of the licence, only one of which discovered hydrocarbons; this being the Dooish gas discovery as drilled by well Ire 12/1-1z (Fig.4). 2 MARCH 2017

3 Table 1: Seismic Data Survey Contractor Type Vintage Status CS9 code OGA15 - Rockall Schlumberger 2D 2015 Proprietary WG152D0001 OGA14 - Rockall Schlumberger 2D 2014 Proprietary WG142D1401 MC 3D 98 SRT * PGS 3D 1998 Speculative PP983DXSRT BP WM Q132 CGG 2D 1991 Proprietary BP912D2001 Outer Hebrides PH1 Western Geophysical 2D 1975 Speculative WG752D0002 OGA15- Rockall Schlumberger 2D 2015 Speculative WG152D0001 BN CGG 2D 1985 Proprietary BN852D2004 BP CGG 2D 1990 Proprietary BP902D1028 BPWM-90 Q132 CGG 2D 1990 Proprietary BP902D2003 UK-FIN97-SF97 HORIZON 2D 1997 Proprietary FN972D1001 SW84 Western Geophysical 2D 1984 Proprietary SH842D1001 * Main seismic dataset Table 2: Offset Well Data Well Year Operator 132/ Conoco Phillips TD (m) Result 4370 P&A Dry 132/ BP 4150 P&A Dry (Ire) 5/ Enterprise 4070 P&A Dry (Ire) 12/02-1,z 2002 Shell 4471 P&A Gas (Ire) 12/ Shell 4456 P&A Dry Comment Targeted large 4-way dip closure. Eocene dominated by claystones with traces of sandstone & limestone. Palaeocene dominated by volcaniclastics & some sandstone (no shows). Prospect failure: lack of charge or no effective reservoir. TD: Upper Cretaceous Shetland Gp. Drilled close to basin margin targeting a pre-rift fault block which turned out to be granitic basement. Well encountered sands within the Eocene, Palaeocene and Cenomanian. No shows seen. Prospect failure: lack of trap? TD: Pre-Cambrian granite. Errigal well tested a large Palaeocene 4-way dip closure. Well failed to find reservoir in target interval, instead encountered a volcaniclastic dominated Palaeocene sequence. Structure likely formed from intrusion of sills. TD: uppermost Cretaceous limestones. Dooish gas discovery. Large tilted fault block. The well encountered over 200m gas-condensate column in pre-rift Permian to Jurassic sandstones. TD: Permian. Drilled on the West Dooish prospect, a hanging wall anticline, downthrown against a N-S fault. No shows. Prospect failure: potentially drilled on a migration shadow. TD: Carboniferous. (Ire) 12/13-1a 1979 Amoco 2869 P&A Dry No Shows, TD Permian. (Ire) 13/ Lundin 1533 P&A Dry Targeted the Inishbeg Triassic prospect. No Shows. (Ire) 13/ Texaco 1366 P&A Dry No Shows, TD in Basaltic Intrusion (Carboniferous). 3 MARCH 2017

4 5 Prospectivity Update A review of the prospectivity has been undertaken to assess the exploration potential. Maps of the seabed and base post-rift section (Fig. 5) show the gross structure of the Rockall Basin within the P.1966 acreage. The seabed dips relatively steeply in a westerly to south westerly direction down from the Hebrides Shelf. Water depths range from 350m in the northeast on the shelf to over 1850m in the west. The majority of the prospectivity sits on the slope within a water depth range of m. The base post-rift map shows two deep basins on the acreage with depths in excess of 7000m TVDss (5650m TVDbml). The age of the strata beneath the base post-rift event varies from Lower Cretaceous and Late Jurassic in the basins (syn-rift) to Triassic and crystalline basement in crestal locations (prerift). Although the Dooish discovery exists regionally and all the elements for a working petroleum system have been proven in the basin, the structural setting for Dooish is somewhat different to that observed on the P.1966 acreage. Dooish is situated on a structural high and consists of a tilted fault block with pre-rift Permian, Triassic and Jurassic sandstone reservoirs. The majority of the P.1966 acreage and underlying stratigraphic units are post-rift (where mapping is possible) and dip basin-ward, without any focus for structural trapping involving counter-dip. Stratigraphic trapping is therefore required to generate prospectivity. A structural basement high was identified to the south of the original P.1966 acreage but this rises up-dip and off the acreage into the Irish sector and consequently was included in the 75% relinquishment. Structural trapping beneath the base post-rift may occur, however imaging in this section is distorted due to volcanic intrusions making this problematic to pursue. Accurate mapping of the base of the extrusive volcanic section in the Palaeocene is difficult but where possible reveals a moderately thick section ( m) of interbedded basalts, volcaniclastics and shales, underneath which an intrusive complex of sills is present within the Lower Palaeocene and Cretaceous. As a consequence, the focus was on the prospectivity of the shallow (post-igneous) section. Figure 6 summarises the prospectivity on P.1966 and indicates the position of seismic lines used in later figures. Figure 7 is a 100 km long regional seismic line running north south over the P.1966 acreage which illustrates the main structural elements and play systems. 5.1 Oligocene Potential The Oligocene section was identified from nearby wells and occurs between the Miocene unconformity and the near Top Eocene major sequence boundaries. Seismic quality is excellent and to be expected given the shallow depth of the unit and lack of volcanics. As there are not any major faults within the Tertiary sequence, charge is considered the main risk for any features identified in the Oligocene. Any oil present would also likely be biodegraded. As a result of this the prospectivity at Oligocene level is considered high risk Casquets Lead Casquets (Fig. 8) is the shallowest of the leads identified and lies stratigraphically above Godrevy and Pendeen (Upper Eocene). Casquets is interpreted as a channel with sand fill, stratigraphically trapped with lateral and up-dip pinch out of the reservoir. Seal is again provided by surrounding mudstones. The only seismic anomaly associated with Casquet is a narrow long hard event interpreted as the base of the channel. A top channel and base channel pick can be made defining the gross geometry of the feature. Seal is again provided by surrounding mudstones. 5.2 Eocene Potential The Eocene section was identified from nearby wells and occurs between major sequence boundaries. Lying directly above the volcanic section imaging of the Eocene is good on the 3D survey. Amplitude anomalies were interpreted as high density slope fans and channel turbidites, stratigraphically trapped 4 MARCH 2017

5 with lateral and up-dip pinch out of the reservoir with seal provided by the surrounding mudstones. Similar features are productive in the North Sea, for example, the Frigg gas field or the Alba oil field Godrevy Lead The Godrevy lead, is interpreted as a turbidite fan sand, consists of an amplitude anomaly with stratigraphic pinch-out laterally and up-dip, with seal provided by surrounding mudstones (Figs. 9 & 10). The amplitude anomaly is a bright peak or positive amplitude which equates to a decrease in acoustic impedance. Down-dip of the bright the seismic character varies somewhat in comparison to the surrounding units. An analogue was drawn with the Tormore oil and gas field with the bright amplitude representing a gas cap and the mapped down-dip portion potentially being oil-filled (Fig.9). Such bright low impedance anomalies may be typical of gas-filled sands. However, the limitations of the available 3D data did not allow for offset gather analysis and an AVO classification could not be attributed to the anomaly, and as such the anomaly could not be fully assessed Pendeen Lead Pendeen is along strike from Godrevy at the same stratigraphic level and is represented by an anomaly of identical seismic character (Figs. 9 & 11). Again an analogue was drawn from the Tormore discovery, but also the Tornado discovery West of Shetland which is almost identical in seismic character, shape and size on full stack data. However, the limitations of the available 3D data did not allow for offset gather analysis and an AVO classification could not be attributed to the anomaly, and as such the anomaly could not be fully assessed Longships Lead Longships while still within the Eocene section above the volcaniclastics lies at a deeper stratigraphic level to Godrevy & Pendeen. Interpreted as an incised sand-filled turbidite channel, the Longships anomaly consists of a bright trough or negative amplitude which equates to an increase in acoustic impedance (Figs. 8 & 12). Such anomalies are not typical of hydrocarbon-filled sands, however, as the relative acoustic impedance signature of the surrounding rocks is unknown (e.g. could the shales be soft and sands hard?) the anomaly may represent hydrocarbons; this uncertainty was risked appropriately. The limitations of the available 3D data did not allow for offset gather analysis and an AVO classification could not be attributed to the anomaly, and as such the anomaly could not be fully assessed. There are a number of these seismically hard channelised features crossing the P.1966 acreage from east to west (Fig. 12). Longships is the largest and most significant of these. 5.3 Palaeocene Potential The Upper Palaeocene section over P.1966 is dominated by a m volcaniclastic sequence which is composed of interbedded basalts, claystones and sandstones. The basalts are easily indenfitifed by their bright hard seismic response. The seismic data in the Lower and Middle Palaeocene section beneath the volcaniclastics is still of sufficient quality to identify channelised features. Intrusive sills are common within this section which does however complicate the interpretation Coquet Lead Figure 9 shows the Coquet Lead which sits within the Palaeocene. This lead is interpreted as a low relief structural four way dip closure of an east-west channel with sand fill. Stratigraphic upside exists with lateral and up-dip pinch out of the reservoir. There is no seismic amplitude anomaly associated with Coquet, rather it is defined by an apparent zone of differential compaction between a top channel and base channel pick beneath the volcanic section and above the Top (Upper) Cretaceous. Seal is provided by surrounding mudstones. Similar features are productive in the North Sea (e.g. the West Brae oil field). 5 MARCH 2017

6 5.4 Cretaceous Potential Mapping of the P.1966 blocks and surrounding area has not allowed for picking of a continuous horizon at Mesozoic level across the entire 3D survey, although picks for the approximate top Upper Cretaceous (Top Maastrichtian) and a Basement or Base post-rift pick have been made across the majority of the survey. Mapping of Intra-Cretaceous markers with confidence is not possible to any great extent and tends to be limited by interference from intrusive sills Wolf Lead The Wolf lead (Fig. 8) is seismically defined as an onlapping package interpreted as stratigraphically trapped deep water mass-flow sandstone (turbidite) enclosed within Upper Cretaceous mudstones. Upper Cretaceous Cenomanian sands are proven in the up-dip 132/15-1 well. This is an untested play in the Rockall Basin, however Cretaceous reservoirs are proven elsewhere along the Atlantic margin (Faroe-Shetland and Voring Basins, along with multiple locations in West Africa). Wolf is represented by a soft peak or positive amplitude which equates to a decrease in acoustic impedance, however the limitations of the available 3D data did not allow for offset gather analysis and an AVO classification could not be attributed to the anomaly, as such this has not allowed it to be fully assessed. Wolf is a similar amplitude anomaly to Bardsey, as an intra-upper Cretaceous anomaly which pinches out against the basement structure. However, the amplitude anomaly does not conform to a likely stratigraphic trap shape. It was retained due to its relative position, beneath Pendeen, as this allowed for potential stacked prospectivity although it was considered to be high risk Bardsey Lead Forming part of the 27 th round application, Bardsey was identified as an Upper Cretaceous soft amplitude anomaly that extends into the Irish sector (DECC Promote 2012). The high amplitude intra- Upper Cretaceous event was interpreted as a possible high-density turbidite sandstone pinching out against the footwall of the Outer Hebrides Platform Basement (Fig. 7), however the amplitude anomaly does not conform to a likely stratigraphic trap shape. The limitations of the available 3D data did not allow for offset gather analysis and an AVO classification could not be attributed to the anomaly, as such this has not allowed it to be fully assessed. Furthermore, as the anomaly and pinch-out edges continued off the acreage to the south and up-dip into the Irish sector, Bardsey was relinquished in Further technical work undertaken The availability of gather data was researched, however the 3D seismic contractor did not retain the gathers used to create the full stack volume, and as such additional data was only available as field data which would have required a reprocessing project out with the remit of the licence work programme. CSEM modelling was undertaken by Petromarker on behalf of the licence to research the feasibility of a CSEM survey as a prospect de-risking tool. Results of the modelling suggest that the vertical distance from Eocene prospect/leads to the underlying igneous lavas/sills may be too small as to allow full resolution of any subtle resistivity anomalies from hydrocarbon filled bodies i.e. any potential hydrocarbon signature from the shallow section would be swamped by the underlying highly resistive igneous units. 6 MARCH 2017

7 7 Resource and Risk Summary Risking and prospective resource volumes for P.1966 are summarised in tables 3 & 4 below. Table 3: Summary of Risk Analysis Lead Source Reservoir Trap Presence Effectiveness Presence Effectiveness Presence Effectiveness COS Casquets Godrevy Gas Godrevy Gas & Oil Pendeen Gas Pendeen Gas & Oil Longships Coquet Wolf Bardsey Table 4: Summary of Resources Name P L D Reservoir Stratigraphic level Unrisked Recoverable Resources Oil (MMbbls) Gas (BCF) P90 P50 P10 P90 P50 P10 Chance of Success (%) Risked P50 (MMboe) Casquets L Oligocene Godrevy (gas only) Godrevy (gas cap & oil leg) Pendeen (gas only) Pendeen (gas cap & oil leg) L Eocene L Eocene L Eocene L Eocene Longships L Eocene Coquet L Palaeocene Wolf L Cretaceous Bardsey L Cretaceous Conclusions Interpretation of the obtained 2D & 3D dataset improved the seismic interpretation, depth conversion and mapping across P Unfortunately the data quality beneath the volcanics and intrusions was not sufficient to allow identification of structurally trapped reservoir intervals within the Mesozoic section. Furthermore the lack of gather data and offset/angle stack volumes hindered seismic anomaly interpretation at the Upper-Cretaceous and Paleogene levels. Consequently it was not possible to mature any of the leads to prospects or drillable status and the licencee/operator has taken the decision to relinquish the acreage. 7 MARCH 2017

8 9 Clearance Parkmead (E&P) Limited confirms that OGA is free to publish this report and that all third party ownership rights have been considered and appropriately cleared for publication purposes. 10 Maps and Figures 8 MARCH 2017

9 3D Seismic Outline Barra Outer Hebrides, Scotland Q142 Q143 Q144 Q132 Q133 Q134 P.1966 United Kingdom Ireland Parkmead Licenced 27 th Round Awarded Blocks Current P.1966 acreage (To be relinquished) Q5 Q12 Q6 Q13 PGS MC-3D survey outline UK/Irish Median Line Irish Sector Licensed Blocks Dooish Unlicensed Blocks Quadrant Boundaries Gas/Condensate Field/Discovery Figure 1: P.1966 Location Map West of Scotland - 9- March 2017

Geikie West Flannan Basin Flannan Basin Rockall Basin Little Minch Basin

Acreage Cretaceous and older Mesozoic / Paleozoic Barra Basin Jurassic

Permo-Triassic Upper Paleozoic Platform containing Paleozoic Basins and

Paleozoic Intrusive bodies N Igneous Bui Igneous Centre 50km Fault Lava

10 Geikie West Flannan Basin Flannan Basin Rockall Basin Little Minch Basin Anton Dohrn Seamount Outer Hebrides Platform 27 th Round Application Acreage Cretaceous and older Mesozoic / Paleozoic Barra Basin Jurassic and older Mesozoic / Paleozoic Hebrides Seamount Stanton Basin Triassic Permo-Triassic Upper Paleozoic Platform containing Paleozoic Basins and Paleogene Lavas Donegal Basin Malin Basin Tertiary and Mesozoic / Paleozoic Intrusive bodies N Igneous Bui Igneous Centre 50km Fault Lava Escarpment Figure 2: Rockall Basin Structural/Stratigraphic Elements March 2017

11 (after Walsh et al, 1999) Figure 3: Play Concept and Migration Model NE Rockall Trough March 2017

P.1966 Relinquishment Report Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 &

1966 acreage (To be relinquished) PGS MC-3D survey outline Q142 Q143

Gas/Condensate Field/Discovery Parkmead Seismic Database PGS MC-3D

FN972D1001 BP902D1028 WG752D0002 United Kingdom Ireland Q5

12 P.1966 Relinquishment Report Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 & 142/28, 29 Parkmead Licenced 27th Round Awarded Blocks Current P.1966 acreage (To be relinquished) PGS MC-3D survey outline Q142 Q143 UK/Irish Median Line Q132 Q133 Blocks Quadrant Boundaries Gas/Condensate Field/Discovery Parkmead Seismic Database PGS MC-3D Survey Coverage WG152D0001 WG142D1401 BP912D2001 BP902D2003 FN972D1001 BP902D1028 WG752D0002 United Kingdom Ireland Q5 WG752D0005 SH842D1001 Q6 Q13 Q12 Dooish Figure 4: Parkmead Seismic & Wells Database March 2017

13 P.1966 Relinquishment Report Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 & 142/28, 29 P.1966 Acreage Depth (m TVDss) Seabed CI = 50m Depth (m TVDss) Base Post-Rift Section P.1966 Acreage CI = 200m Figure 5: Seabed & Base Post-Rift Structure (Depth m TVDSss) March 2017

14 A 3D Seismic Outline Pendeen (oil leg case) Pendeen Wolf D D Godrevy C C P.1966 Acreage Godrevy (oil leg case) B Longships Casquets Coquet (4-way dip) Coquet (channel) B Original P th round award Bardsey A Figure 6: Prospect/Leads Summary Map (also positions of seismic lines from Figures 7, 8 & 9) March 2017

15 P.1966 Relinquishment Report Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 & 142/28, 29 A B north south Seismic Image Courtesy of PGS Casquets Pendeen Godrevy Longships Two Way Time (secs) Coquets U. Palaeocene Volcaniclastics Upper Cretaceous Bardsey Wolf Basement 0 km 10 Syn/Pre-rift Sequence in Grabens not penetrated in offset wells source potential PLAY SYSTEMS Oligocene turbidite channels Eocene turbidite slope fans (above volcanics) Eocene turbidite channels (above volcanics) Palaeocene turbidite channels (below volcanics) Cretaceous turbidite fans Figure 7: North-South Regional Seismic Line A-A Casquets Pendeen, Godrevy Longships Coquets Wolf, Bardsey March 2017

SEABED north 1.9 2.1 2.3 MIOCENE U/C 2.5 CHANNEL BASE 2.

3 TOP VOLCANICLASTIC UNIT 3.5 Coquets 3.7 3.9 4.

16 P.1966 Relinquishment Report 1.7 Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 & 142/28, 29 B B south SEABED north MIOCENE U/C 2.5 CHANNEL BASE 2.7 TOP UPPER EOCENE 2.9 Longships TOP VOLCANICLASTIC UNIT 3.5 Coquets TOP UPPER CRETACEOUS 4.3 Seismic Image Courtesy of PGS 0 km 2.5 Figure 8: Coquet, Casquets, Longships Seismic Section B-B March 2017

17 P.1966 Relinquishment Report Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 & 142/28, 29 C C D D west east west east km Seismic Image Courtesy of PGS Figure 9: Godrevy, Pendeen, Wolf Seismic Sections Seismic Image Courtesy of PGS km 2.5 March 2017

18 Depth (m TVDss) Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 & 142/28, 29 Location of Seismic Line A-A P.1966 Relinquishment Report Amplitudes Location of Seismic Line A-A CI = 20m Figure 10: Godrevy Lead Depth and Amplitude Maps March 2017

19 Depth (m TVDss) CI = 20m Location of Seismic Line A-A Location of Seismic Line A-A Amplitudes Figure 11: Pendeen Lead Depth and Amplitude Maps March 2017

Depth (m TVDss) Amplitudes Blocks 132/3, 4,

20 Depth (m TVDss) Amplitudes Blocks 132/3, 4, 8, 9, 13, 14, 18, 19 & 142/28, 29 Location of Seismic Line A-A P.1966 Relinquishment Report CI = 50m RMS Amplitude window ms above the top Volcaniclastic unit Figure 12: Longships Lead Depth and Amplitude Maps March 2017

UK P2060, Block 29/06b Licence Relinquishment

ENDEAVOUR ENERGY UK LIMITED UK P2060, Block 29/06b Licence Relinquishment ISSUE RECORD SUMMARY Dec 2015 Final Graham Tegerdine Rev Date Description Document Owner Review Required By Table of Contents 1