The Athena gas discovery is located at a water depth of 1,769m in Block 12, offshore Israel, within the country’s exclusive economic zone (EEZ).
The block containing the discovery is owned by UK-based Energean, an oil and gas exploration and production company. The company is focused on developing gas resources in the Mediterranean Sea.
It announced the Athena commercial gas discovery in May 2022.
Athena is part of the Olympus Area, which also includes the undrilled prospects on Block 12 and the adjacent Tanin Lease.
Energean is currently pursuing commercial development options for the wider Olympus Area through domestic gas sales and exports.
The options include new gas sales and purchase agreements (GSPA) as well as expanding the memorandum of understanding (MoU) signed with the Egyptian Natural Gas Holding Company (EGAS) in December 2021 for the supply up to three billion cubic metres (bcm) a year into a binding agreement.
The company is also exploring the option of exporting to other regional and European markets.
Athena discovery location and reserves
The Athena gas discovery is located within the Olympus Area in the Mediterranean Sea, offshore Israel, about 20km from the Karish field as well as the Tanin A development.
Based on preliminary analysis, the discovery is expected to hold recoverable gas volumes of 8bcm.
Athena gas discovery details
The discovery was made by the Athena exploration well, which was drilled by the Stena Icemax drillship in 51 days. The well was Energean’s fifth consecutive well to be drilled successfully offshore Israel.
The Athena exploration well encountered a gross hydrocarbon column of 156m in the A, B and C sands, which was the primary target. However, it did not hit commercial hydrocarbons in the deeper D sands, which was the secondary target.
The well was suspended as a future production well following the discovery.
Energean is exploring multiple options for the development of the Athena discovery. One of the options is to develop the discovery as a tie-back to the Energean Power floating, production, storage and offloading (FPSO), which is a new FPSO unit built for the Karish-Tanin field.
The FPSO arrived at the Karish gas field location in June 2022.
The tie-back would help commercialise the discovery in the near-term, while also increasing the value of the Karish-Tanin field development.
Another option is to develop the discovery as part of the Olympus Area development.
Energean plans to conduct additional analysis to further refine the full resource potential of the Athena gas discovery. This analysis will include the volumes contained within thinner sands between the main reservoir units as well as confirming the liquids content of the discovery.
Energean Power FPSO details
The Energean Power FPSO is planned to be installed 90km offshore Israel to operate in the Karish field. It will be the first FPSO ever to be operated in the Eastern Mediterranean.
The FPSO is expected to have a gas treatment capacity of 800 million metric standard cubic feet per day (Mmscfd), while the liquids storage capacity is estimated to be 800,000 barrels.
It is also expected to provide increased production capacity for potential additional projects in the future.
Olympus Area details
The Israeli Petroleum Commissioner awarded five offshore exploration licences, comprising Blocks 12, 21, 22, 23 and 31, within the EEZ of Israel to Energean in December 2017.
The Olympus Area comprises Block 12 and the prospects on the Tanin lease, which was acquired in December 2016, along with the Karish development lease.
The discoveries and prospects in the Olympus area are situated along the same geological trend as the Athena discovery.
The Athena exploration well was drilled on the same direct hydrocarbon indicator, which is an anomalous seismic amplitude, as Tanin.
The Tanin field is located at a water depth of about 1,800m, approximately 110km north of Israel’s EEZ in the Levantine basin.
The A, B and C sands in the remaining prospects of the Olympus Area are estimated to contain 50bcm of mean unrisked prospective resources, excluding liquids or gas upside in the thinner sands between the main reservoir units.
Stena IceMax drillship details
The Stena IceMax drillship is claimed to be the world’s only sixth-generation Ice-class dynamically positioned (DP3) harsh environment dual mast ultra-deepwater drillship.
It has a length of 228m and breadth of 42m as well as accommodation for 180 persons, which can be increased to 220 persons.
The drillship can operate at a maximum water depth of 10,000ft (3,048m) and has a maximum drilling depth of 35,000ft (10,668m).
The drillship is equipped with an NOV dual hoisting and drilling tower. The top drive consists of a main NOV HPS-03 1000, two ABB HXR 450 (LM6) AC-motors and an auxiliary NOV HPS-03 750 top drive, with two ABB HXR 450 (LM8) AC-motors. The mud pump units use four National FC2200 pumps.
The drillship’s main power system comprises six Wartsila 16V32C diesel engines and six ABB AMG 1120MR10 LSE alternators.
Energean signed a contract with drilling contractor Stena Drilling in June 2021 for the drilling of three firm wells, including the Karish North development well and Athena exploration well. The contract also includes two optional wells.