Relinquishment Report - Oil and Gas Authority Report for Licence P1816 Estimates, statistics,...

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Relinquishment Report for Licence P1816 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, TOTAL undertakes no obligation to provide the recipient with access to any additional information.

Transcript of Relinquishment Report - Oil and Gas Authority Report for Licence P1816 Estimates, statistics,...

Relinquishment Report for

Licence P1816

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, TOTAL undertakes no obligation to provide the recipient with access to any additional information.

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TABLE OF CONTENTS:

1 LICENCE INFORMATION ..............................................................................................................3

2 LICENCE SYNOPSIS ......................................................................................................................3

3 WORK PROGRAMME SUMMARY ................................................................................................4

4 DATABASE ..................................................................................................................................4

5 PROSPECTIVITY UPDATE .............................................................................................................7

5.1 SCARINISH ........................................................................................................................................ 7 5.2 ADDITIONAL PROSPECTIVITY ................................................................................................................ 9

6 FURTHER TECHNICAL WORK UNDERTAKEN ............................................................................... 10

7 RESOURCE AND RISK SUMMARY ............................................................................................... 10

8 CONCLUSIONS .......................................................................................................................... 10

9 CLEARANCE .............................................................................................................................. 10

TABLE OF FIGURES:

Figure 1: Location of licence P1816............................................................................................................... 3 Figure 2: 29/15-1 & 29/15-2 Well Summaries .............................................................................................. 5 Figure 3: Random line showing reprocessing to PSDM (bottom) compared with Legacy Regional PSTM (top) ............................................................................................................................................................... 6 Figure 4: Random line showing relative seismic impedance volume in the P1816 area............................... 7 Figure 5: Seismic line through Scarinish Prospect at time of licence application ......................................... 8 Figure 6: Seismic line through Scarinish showing post Romeo well interpretation ...................................... 9

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1 LICENCE INFORMATION

Licence Number: P1816 Licence Round: 26th Round licence Licence Type: Traditional Block Number: 29/15a Relinquished: 5th January 2017 Total E&P UK Ltd confirms OGA 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 Licence P1816, consisting of Block 29/15a, was awarded to Total E&P UK (100 % TEPUK) as part of the 26th UKCS Licensing Round (Figure 1). The Licence was covered by an Initial Term of 4 years from the Start Date of 10th January 2011, which was then later extended until 31st December 2016 The main prospect on the licence identified at the time of the 26th Round application was the Upper

Jurassic aged Scarinish, consisting of a three way dip closure against an E-W southern bounding fault. A

second Jurassic prospect, Fingal-Romeo was also identified, straddling the block boundary with 30/11c.

Figure 1: Location of licence P1816

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3 WORK PROGRAMME SUMMARY

The agreed work programme consisted of firm commitments to: Reprocess 200km2 of 3D seismic data to PreSDM

Drill a well to 4900m or the Zechstein salt, whichever is the shallower, on the Romeo-Fingal

Prospect

Drill a well to 4900m or the Zechstein salt, whichever is the shallower, on the Scarinish Prospect

The first firm exploration commitment well (30/11c-6C) was drilled on the Romeo-Fingal structure straddling the P1816 and P1666 licences (Joint well operated by SUNCOR ENERGY; spud date: 28th September 2012). The well was P&A as a sub-economic oil discovery at Upper Jurassic and Triassic levels, after finding much lower net sands than expected in the Fulmar main objective section. These results have downgraded the nearby Upper Jurassic Scarinish prospect. After extensive and unsuccessful efforts to farm-out the acreage, including the remaining well commitment, TEPUK received OGA agreement to transfer the commitment to another licence.

4 DATABASE

Well data

There is currently one well penetration on the P1816 Licence. Exploration Well 29/15-1 (Figure 2) drilled by Shell in 1977 in the southern part of the P1816 Licence. It was targeting as a primary objective the Fulmar sands in a fault and dip closed structure. The well encountered organic Upper Jurassic clays overlaying Triassic reddish fine-grained sandstone and mudstone (no Fulmar sands were found at the well). Triassic Skagerrak Formation was found water-bearing and with low porosity. The well was abandoned as a dry hole. Well 29/15-2 (Figure 2) was drilled by Shell in 1991 just to the north of the P1816 Licence. The well was targeting the Upper Jurassic Fulmar in a combined fault/dip closure with a stratigraphic trapping component formed by Triassic and Upper Jurassic shales. The well found 32m of tight, very fine and bioturbated (low porosity and permeability) water-bearing sandstone in the Upper Jurassic. This well was mainly used to constrain the velocity information used in the time-depth conversion of the interpreted horizons over the Scarinish area.

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Figure 2: 29/15-1 & 29/15-2 Well Summaries

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The Romeo-Fingal well 30/11c-6C was drilled by SUNCOR ENERGY in 2012 on the P1666 Licence, and is located just to the east of the P1816 Licence. The well found oil in the Upper Jurassic and in the Triassic. Upper Jurassic Fulmar reservoir, with poor reservoir characteristics, was interpreted as dominantly mud-prone shelf heterolithics with rare sandy layers. No Oil/Water contact was clearly identified from logs. The well was P&A with no DST performed, and the P1666 licence was relinquished in February 2016. Seismic Data As part of the licence commitment, 414km2 of spec 3D Marine seismic data acquired in 2001/2002 by CGGVeritas was processed using PSDM between September 2010 and January 2012. In parallel, 628 km2

of data was reprocessed using PSTM. The reprocessing provided improved structural images compared to the regional CGGV Long Offset data that were used for the application (Figure 3). The PSDM data was used as the input to an acoustic inversion carried out in 2013 by Fugro-Jason. This product was used qualitatively to indicate the presence of Fulmar reservoir in the licence and surrounding area (Figure 4).

Figure 3: Random line showing reprocessing to PSDM (bottom) compared with Legacy Regional PSTM (top)

(Courtesy of CGG Multi Client Long Offset data)

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Figure 4: Random line showing relative seismic impedance volume in the P1816 area

5 PROSPECTIVITY UPDATE

5.1 Scarinish

At the time of the 26th Round application, the Scarinish prospect was interpreted as an east-west elongated anticlinoform structure rotated over a major east-west north dipping salt body (Figure 5). The primary reservoir objective was the Fulmar (mid-Oxfordian to Kimmeridgian) shoreface sandstone stacked in a wedge expanding during an Upper Jurassic syn-sedimentary salt withdrawal and Rotliegend basement tectonics. It was defined by clear picking of the top Fulmar, top Pentland, top Triassic, and top Zechstein salt and tied to neighbouring reference wells 29/15-1 and 29/15-2. The prospect had pre-drill mean unrisked resources of 79 Mboe. Following the drilling of the Romeo-Fingal exploration well, 30/11c-6C, in 2012, which encountered lower to middle marine shoreface sands that had undergone intense carbonate diagenesis, it was believed that the probability of encountering better quality reservoir at Scarinish is low (Figure 6). Therefore, reservoir quality is seen as a critical risk factor at Scarinish. Whilst Scarinish is dependent upon downthrown fault seal against the Triassic (Figure 6), the c.180 Bar overpressure differential between 30/11c-6C and 29/15-1 suggests that the fault is likely to be sealing. Regional synthesis and structural restoration studies were carried out but they were not able to permit a more optimistic interpretation of the Scarinish prospect. The negative well results at Romeo-Fingal resulted in a significant decrease of Scarinish recoverable resources (see table below). These resources were insufficient to proceed with drilling and the decision was taken to fully relinquish the licence at the end of the extended Initial Term.

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Figure 5: Seismic line through Scarinish Prospect at time of licence application

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Figure 6: Seismic line through Scarinish showing post Romeo well interpretation

5.2 Additional Prospectivity

In addition to the prospects identified at the time of the application a full screening has been undertaken on the P1816 Licence. No significant additional prospectivity has been identified as discussed below. Tertiary: Based on the amplitude extractions at Top Lista a potential Palaeocene fairway was also identified in the northern part of the Licence but the main prospective area is largely outside (Licence P1666). No other prospective structures exist within the block 29/15a at Tertiary – Palaeocene level. Upper Jurassic Scarinish is the main undrilled structure identified at Upper Jurassic level within the Exploration License P1816. No other prospects at Upper Jurassic level were identified within the block 29/15a. Triassic A small 3-way dip closure was identified at Triassic in the northern part of the block. Seismic interpretation suggests a critical risk of charging due to the lack of extensive reservoir-source

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juxtaposition. Due to the small areal size (~2 Km2) and the high risk of charging and lateral seal, this structure has not been included in the calculation of prospective resources of the P1816 Licence. Permian (Rotliegend) Within the P1816 license, Rotliegend fault blocks are bounded by salt towards North and East and the critical risk is related to the charging and migration (no direct communication with the Kimmeridge Clay kitchen). Taking into account the small size of the remaining structural closures and the high risk for charging/migration, remaining prospectivity is considered as low at Rotliegend level.

6 FURTHER TECHNICAL WORK UNDERTAKEN

No additional technical work was undertaken.

7 RESOURCE AND RISK SUMMARY

No commercial discovered resources exist in the P1816 Licence. The nearest discovered resource is the sub-commencial 30/11c-6C pre-BCU Romeo-Fingal oil discovery, which extends onto the east of the Licence.

8 CONCLUSIONS The current evaluation, updated taking into account the Romeo-Fingal well results, downgrades the volumetrics on the Scarinish prospect. Such a drop in resources, coupled with the current oil price scenario, means that this prospect has no current economic value.

9 CLEARANCE

Total E&P UK Ltd confirms OGA is free to publish this report and that all third party ownership rights have been considered and appropriately cleared for publication purposes. The 3D CGGV seismic data is held under licence and is property of CGGV.