E&P Notes (September 2022)
Authors: JPT staff _ 
Published: October 2022

Tullow Swings and Misses off Guyana
Tullow Oil has come away empty with its Beebei-Potaro exploration well, drilled in the Kanuku license, offshore Guyana. According to the company, the well encountered good quality reservoir in the primary and secondary targets but both targets were water-bearing. Noble jackup Regina Allen drilled the well to a total depth of 4325 m in 71 m of water. The well has been plugged and abandoned.
Tullow will integrate the well results into its regional subsurface models and work with its joint venture partners before deciding on next steps.
Repsol is the operator of the Kanuku license with a 37.5% working interest. Tullow holds 37.5% with TOQAP—a joint venture between TotalEnergies and Qatar Petroleum—holding 25%.
Tullow previously said it would limit capital exposure in Guyana. The company holds a 60% interest in the Orinduik block, its other licensed area in Guyana, with partners including TotalEnergies and Eco Atlantic Oil & Gas.

Oxy Brings Horn Mountain West Online in GOM
Occidental has successfully turned the taps on its Horn Mountain West subsea field in the Mississippi Canyon area of the Gulf of Mexico (GOM). The field is in about 5,400 ft of water. The $250-million project comprises a pair of wells tied back to the existing Horn Mountain spar in Block 126 via a 3½-mile dual flowline. According to Oxy, the project came in on budget and 3 months ahead of schedule. It is expected to eventually add approximately 30,000 BOPD. Horn Mountain initially came on stream in late 2002.

Hess Strikes Miocene-Aged Oil at Huron in GOM
Hess made an oil discovery with a well at its Huron prospect in the Green Canyon area of the deepwater GOM. The well, drilled in Block 69 to a target depth of 28,900 ft by Transocean drillship Deepwater Asgard, struck high-quality, oil-bearing Miocene-aged reservoirs and established the existence of a working petroleum system. An up-dip sidetrack to the initial probe is planned.
Gregory Hill, Hess’ chief operating officer, told investors in July that … “as a result of what we’re seeing at Huron we see additional prospectivity in that northern Green Canyon area, and we have a very competitive leasehold position there.” The company had stated previously that its position in the northern Green Canyon area has a high potential for multiple, high-return hub-class Miocene opportunities.
Hess operates Huron with a 40% interest. Partners Chevron and Shell each hold 30% stakes. Hess struck a deal with both Chevron and Shell to farm into the prospect in February 2022. The Huron well marks Hess’ return to exploration drilling in the deepwater GOM for the first time in around 2 years.

Wintershall Dea Turns the Taps at Nova
Wintershall Dea started production from the Nova oil field in the Norwegian North Sea. The field comprises two subsea templates, one with three oil producers and one with three water injectors, tied back to the Gjøa platform.
The expected recoverable gross reserves from the field are estimated at 90 million BOE, of which the majority will be oil. The operator said the completion of Nova emphasizes its strength as one of the largest subsea operators on the Norwegian Continental Shelf. “With the startup of the major project Nova, Wintershall Dea is now operating three subsea production fields in Norway,” said Hugo Dijkgraaf, member of the executive board and chief technology officer.
The Dvalin field and the partner-operated Njord Future project, in which Wintershall Dea holds a 50% share, are planned to come on stream later this year. The company also operates recent discoveries like Dvalin North, planned for PDO hand-in (Plan for Development and Operations) by the end of 2022, and several other discoveries which could be developed in the future. Wintershall Dea is a partner in the Aker BP-operated Storjo discovery in the Norwegian Sea.
Wintershall Dea operates the Nova field with a 45% stake, of which it plans to transfer 6% to OKEA in Q4 this year; Sval Energi holds 45%, Pandion Energy Norge, 10%.

Eni Touts Potential 3.5-Tcf Gas Find With First Offshore Abu Dhabi Well
Eni believes it has discovered an additional 1.0 to 1.5 Tcf of raw gas in place, in a deeper zone, in its first exploration well drilled in Offshore Block 2 Abu Dhabi. The discovery follows an initial finding in a shallower zone of the same well, aggregating to a total gas in place of up to 3.5 Tcf.
The Italian operator said gas-bearing reservoirs were tested with excellent flow rates and fast-track development options are currently under evaluation.
Eni, operator, holds a 70% stake in Block 2; PTTEP holds the remaining 30%.
Eni has been present in Abu Dhabi since 2018. It operates three exploration concessions and participates with ADNOC in three offshore development and production concessions: Lower Zakum (5%), Umm Shaif and Nasr (10%), and Ghasha (25%).

Petrobras Makes Gas Discovery in Colombia
Petrobras confirmed the discovery of natural gas accumulation in the Uchuva-1 exploratory well drilled in the deep waters 32 km off the coast of Colombia. The discovery is about 76 km from the city of Santa Marta in a water depth of approximately 830 m.
The well was drilled in the Tayrona block, with operator Petrobras (44.44%) in partnership with Ecopetrol, who holds the remaining stake. The consortium will continue its activities in the block to assess the dimensions of the new gas accumulation.

CNOOC Successfully Tests Offshore Shale Well
China’s CNOOC Ltd. tested commercial flows of oil and gas from an offshore shale exploration well in the South China Sea, marking the first successfully drilled shale oil well offshore China, state media reported in early August.
Exploration well Weiye-1, drilled at the southwestern trough of Beibuwan basin, tested daily production of 126 bbl of oil and 1589 m3 of natural gas. CNOOC estimated that the shale oil resources in the entire basin are about 8.8 billion bbl, suggesting good exploration prospects.
With the Chinese government stressing added volumes for its domestic energy supply security, national oil companies are making greater efforts to tap shale deposits despite being tougher to drill and more expensive. As of late 2021, China produced only 35,000 B/D of shale oil, mostly in the onshore northern Ordos basin and northwestern Jungar basin.

Eni Strikes Oil With Baleine East Well in Côte d’Ivoire
Eni has encountered oil with its Baleine East 1X well, the first exploration well in block CI-802 and second discovery on the Baleine structure offshore Côte d’Ivoire. The results have prompted a 25% increase in the oil and gas volumes in place, which are now estimated at 2.5 billion bbl of oil and 3.3 Tcf of associated gas.
The well was drilled in the block operated by Eni (90%), together with its partner Petroci Holding (10%), using the drillship Saipem 12000. The final depth reached was 3165 m measured depth, in a water depth of about 1150 m. Baleine East 1X is located about 5 km east of the Baleine 1X discovery well in the adjacent block CI-101 and represents the first commercial discovery in the CI-802 block, confirming the extension of the Baleine field.
The well confirmed the presence of a continuous oil column of about 48 m in reservoir rocks with good properties. From the vertical borehole, a horizontal drain of 850 m in length was subsequently drilled into the reservoir to perform a production test that confirmed potential production of at least 12,000 BOPD from the Baleine East 1X well.
A third well will be drilled to ensure the accelerated startup of production and confirmation of first oil in the first half of 2023.
In addition to blocks CI-101 and CI-802, Eni owns interests in five other blocks in the Ivorian deep water: CI-205, CI-501, CI-504, CI-401, and CI-801, all with the same partner, Petroci Holding.

Neptune Energy Kicks Off Ofelia Exploration Well
Neptune Energy began drilling operations on the Ofelia exploration well in the Norwegian sector of the North Sea. The well, 35/6-3 S, is being drilled by the Odfjell Drilling-operated semisubmersible Deepsea Yantai. The prospect is located 13 km north of the Gjøa field within the Neptune-operated PL929 License.
If commercial, Ofelia could be tied back to the Neptune-operated Gjøa platform and produce at less than half the average carbon intensity of Norwegian Continental Shelf fields, according to the company. Neptune said it could potentially be developed in parallel with Hamlet (PL153).
Ofelia is positioned in one of Neptune’s core areas and close to existing infrastructure. The reservoir target is the Lower Cretaceous Agat Formation and is expected to be reached at a depth of approximately 2570 m. The drilling program comprises a main bore (35/6-3 S) with an optional sidetrack (35/6-3 A) based on the outcome of the exploration well.
Neptune Energy operates Ofelia with a 40% working interest. Partners are Wintershall Dea (20%), Aker BP (10%), Pandion Energy (20%), and DNO (10%).

Partners Continue Successful Drilling in Algerian Desert
Eni and partner Sonatrach revealed a further discovery in the Zemlet el Arbi concession, located in the Berkine North Basin in the Algerian desert.
The Rhourde Oulad Djemaa Ouest-1 (RODW-1) exploration well, in the Sif Fatima II research perimeter, is the third well in the exploration drilling campaign. It led to a discovery of oil and associated gas in the Triassic sandstones of the Tagi reservoir. During its production test, the well produced 1,300 BOPD and about 2 MMcf/D of associated gas.
The RODW-1 discovery comes after the significant discovery of HDLE-1, announced in March 2022, and the successful second appraisal well HDLS-1 in the adjacent Sif Fatima II. Because of their proximity to existing BRN/ROD facilities, the development of these discoveries will be fast-tracked.
The Zemlet el Arbi concession is operated by a joint venture between Eni (49%) and Sonatrach (51%). The discovery is part of the new exploration campaign which will include the drilling of five wells in the Berkine North Basin.