Glaucus & Pegasus
Resource Potential
Much of the uncertainty has now been resolved. The Pegasus discovery of July 2025 added a second field to Block 10, and on 30 June 2026 Cyprus, ExxonMobil and QatarEnergy declared Glaucus and Pegasus commercial with an estimated 7-9 tcf combined. Pegasus itself has yet to be fully quantified, with appraisal drilling planned for end-2026. Remaining upside lies in untested prospects and adjacent acreage.
Updated July 2026 · Sources: MECI, ExxonMobil, press reports
Resource Scenarios
Confirmed Resource (Glaucus + Pegasus)
Figure cited at the 30 June 2026 Declaration of Commercial Discovery (the September 2025 government confirmation had said 8-9 tcf). Official Glaucus GIIP is 3.7 tcf after the 2022 appraisal; the split is unofficially put at ~3.2 tcf Glaucus and ~5 tcf Pegasus, with Pegasus yet to be fully quantified.
Exploration Upside
ExxonMobil will reprocess seismic over Blocks 4 and the new "10A" designation before deciding whether to drill. Energy Minister Michael Damianos has also flagged a possible new licensing round within 1-2 years. Further prospects remain untested.
Updated July 2026 · Sources: Declaration of Commercial Discovery (Jun 2026), MECI
What Could Add Volume?
New Acreage (Blocks 4 & 10A)
ExxonMobil will reprocess seismic over Blocks 4 and "10A" before deciding on drilling
UnquantifiedDeeper Reservoirs
Untested deeper zones may contain additional gas accumulations
UntestedProven Play Extension
Pegasus (~350m gas column) confirmed the play concept works beyond the original Glaucus structure
De-risks nearby prospectsBetter Recovery
High-quality reservoirs could support strong recovery factors
Development-dependentRegional Comparison
| Field | Country | Reserves | Status |
|---|---|---|---|
| Zohr | Egypt | 30 Tcf | Producing |
| Leviathan | Israel | 22 Tcf | Producing |
| Glaucus + Pegasus | Cyprus | 7-9 Tcf | Development |
| Tamar | Israel | 10 Tcf | Producing |
| Aphrodite | Cyprus | ~3.7 Tcf | Development |
At 7-9 tcf combined, Glaucus and Pegasus rank among the larger gas resources in the Eastern Mediterranean.
Updated July 2026 · Sources: Operator disclosures, government statements
Path to Development
With commerciality declared, Block 10 has entered the development phase. Key milestones and open questions:
Pegasus Discovery (July 2025)
Drilled by the Valaris DS-9; roughly 350m gas column, 190km southwest of Cyprus in 1,921m of water.
Commerciality Declaration (30 June 2026)
Cyprus, ExxonMobil and QatarEnergy signed the Offshore Cyprus Declaration of Commercial Discovery in Nicosia, moving Glaucus and Pegasus into the development phase.
Pegasus Appraisal (end-2026)
A rig is under contract with delivery expected around December 2026; wells are being designed and permitted. Appraisal drilling will feed into FEED.
Development Concept (open)
The leading concept is a subsea pipeline into Egypt's existing LNG infrastructure; FLNG and onshore LNG remain alternatives, though onshore would require more resource than currently discovered.
FID ~2029, Production ~2033
Timeline indicated by ExxonMobil VP John Ardill at the June 2026 declaration ceremony.
What 7-9 Tcf Means for Cyprus
At 7-9 tcf, Block 10 could generate tens of billions of dollars in government revenues over the field life, transforming Cyprus's fiscal position.
Glaucus in the News
ExxonMobil’s East Med strategy enters a new phase
The Commerciality Declaration for Cyprus’ Glaucus and Pegasus gas discoveries made this week marks an important milestone – not only for the island, but also for ExxonMobil’s wider Eastern Mediterranean strategy. After almost eight years of exploration, the company has formally moved from proving...
The landscape is changing in Cyprus’ exclusive economic zone
The Republic of Cyprus, ExxonMobil and QatarEnergy recently signed a tradability statement for the Glaucus and Pegasus gas fields. This marks a significant step forward in Cyprus’ energy programme. It is clear evidence — a vote of confidence — in the prospects of Cyprus’ exclusive economic zone, ...
ExxonMobil eyes 2033 production start at Cyprus gas fields
Cyprus, ExxonMobil and QatarEnergy have signed a declaration of commerciality for the Glaucus and Pegasus natural gas fields, moving the discoveries from the exploration phase into development. President Nikos Christodoulides described the move as a “milestone of strategic importance” for Cyprus’...
QatarEnergy, ExxonMobil Declare Cyprus Gas Discoveries Commercial
QatarEnergy, ExxonMobil and the Government of Cyprus have signed a commercial discovery declaration for the Glaucus and Pegasus fields in Block 10 offshore Cyprus…
Cypriot gas fields declared ‘marketable’ by energy giants
Two gas fields located in Cyprus exclusive economic zone (EEZ) were on Tuesday declared “marketable” by multinational energy corporations ExxonMobil and QatarEnergy. Both fields, the ‘Pegasus’ field and the ‘Glaucus’ field, are located in Block 10 of Cyprus’ EEZ, with ExxonMobil and QatarEnergy h...