Projects

Mereenie, Palm Valley & Dingo,
Northern Territory, Australia

Horizon Interest: 25.0% direct working interest / approximately 29.3% effective interest including Cue.¹

Australia

Northern Territory oil and gas assets

Horizon’s Australian portfolio comprises interests in the Mereenie, Palm Valley and Dingo fields in the Northern Territory’s Amadeus Basin. The portfolio combines Horizon’s own interest in Mereenie with interests held through Cue Energy.

Mereenie

Asset Overview

Horizon Interest: 25.0% direct working interest / approximately 29.3% effective interest including Cue.¹

JV: Central Petroleum (25% – Operator), Echelon (42.5%), Cue Energy (7.5%)
~250km west of Alice Springs
Cashflows underpinned to at least 2028 by gas sales agreements
FY26 cash operating costs were approximately US$12/boe produced, excluding royalties

Recent Highlights from FY2026

FY26 production was supported by the continued performance of the WM29 and WM30 development wells, stronger contracted gas pricing and the gas supply agreement executed with McArthur River Mining in October 2025
The Letter of Intent with Power and Water Corporation for a proposed new Mereenie gas sales agreement expired in April 2026 without agreement on replacement terms
The existing PWC gas supply agreement remains in place through 2030. In the absence of a new agreement, the Joint Venture suspended further work on the proposed additional two-well infill program
Well planning, long-lead procurement and drilling preparations are substantially advanced, enabling the program to progress at relatively short notice if gas contracting outcomes and market conditions support investment
The Joint Venture continues to pursue commercially acceptable gas sales arrangements

Transaction Overview

In February 2024 Horizon announced the execution of a sale and purchase agreement with Macquarie Mereenie to acquire a 25% non-operated participating interest in the NT Mereenie oil and gas field
Upfront cash consideration of ~US$27.6 million (A$42.5 million), effective 1 April 2023, with deferred/contingent payments of US$5.8 million (A$9 million) payable over 24 months
Headline cash consideration fully funded from a new 5-year Macquarie Bank debt facility
Transaction enables the Company to maintain it’s current distribution strategy, while enhancing cashflows and diversifying and growing the production base

Background

The field was discovered in 1964 and first production was in 1984.

The Operator, Central Petroleum, acquired a 50% interest from Santos in June 2015. The remaining 50% was acquired by Macquarie Mereenie in December 2016. In October 2021 NZOG acquired a 17.5% interest in the licence from Central Petroleum and Cue Energy a further 7.5%, with Central Petroleum’s interest reducing to 25%.

The field comprises OL4 and OL5 tenement areas (123 km² and 158 km² respectively). The field is ~40 km long and ~4km wide. The principal oil and gas reservoirs are the P1 and P3 units of the Pacoota Sandstone. Resources have also been identified in the Pacoota P4 unit and in the Stairway Sandstone.

A total of 73 wells have been drilled in the field. There are two processing facilities, comprising the Central Treatment Plant (CTP) and the Eastern Satellite Station (ESS).

The initial development focused on the oil rim with some gas exported and the remainder reinjected. The development turned to a gas export focus in 2018 when the Northern Gas Pipeline (NGP) was commissioned, linking the NT to East Coast gas markets. The facilities underwent an upgrade in 2018 increasing the gas processing capacity to 58 TJ/d.

Gas is exported via the Amadeus Gas Pipeline and the downstream NGP.

Crude oil and condensate is currently trucked to Port Bonython, in South Australia, prior to export by tanker, normally to refineries in Singapore.

Palm Valley

Asset Overview

Horizon Interest: Approximately 8.6% effective interest through Cue.¹

Cue holds a 15% interest in OL3, operated by Central Petroleum. Palm Valley supplies gas to Northern Territory and East Coast markets under long-term gas sales arrangements. A two-well appraisal program comprising PV14 and PV15 is intended to evaluate additional gas resources and support future Northern Territory gas supply. PV14 was spudded in July 2026

Recent Highlights from FY2026

A long-term gas supply agreement with the Northern Territory Government supports a two-well appraisal program comprising PV14 and PV15. The program is designed to assess additional gas resources and future supply. Drilling commenced in July 2026 with the spudding of PV14

Background

Palm Valley lies approximately 100 kilometres west of Alice Springs and began production in 1983. The field connects to the Amadeus and Northern Gas pipeline systems

Dingo

Asset Overview

Horizon Interest: Approximately 8.6% effective interest through Cue¹.

Cue holds a 15% interest in L7, operated by Central Petroleum. Dingo supplies gas under a long-term contract supporting electricity generation in Alice Springs. Production remained stable during FY26

Recent Highlights from FY2026

Production remained stable during FY2026

Background

Dingo was discovered in 1985. Its gas is processed at the Brewer Estate facility near Alice Springs and supplied by pipeline to Owen Springs Power Station

1. Effective interests include Horizon’s proportionate interest through its 57.03% controlling shareholding in Cue Energy Resources Limited where applicable. The underlying licence interests remain legally held by Cue.