ADX Energy Strikes Gas at HOCH-1 in Upper Austria

ADX Energy Strikes Gas at HOCH-1: Austria's Shallow Gas Play Delivers Its First Drilling Result

ADX Energy (ASX: ADX) has announced a significant early-stage result from its Hochfeld-1 (HOCH-1) well in Upper Austria, with gas-filled sands encountered in the Hall formation at approximately 1,350 metres depth. The ADX Energy HOCH-1 gas discovery in Austria aligns almost exactly with the company's pre-drill 3D seismic predictions — a technical validation that meaningfully strengthens confidence across ADX's broader shallow gas programme in the region.

This is the first of three permitted shallow gas wells the company plans to drill in 2026, and the early result has set a promising tone for what could become a multi-well discovery campaign.

Gas in the Ground: What the HOCH-1 Drilling Results Show

The confirmation of gas at HOCH-1 is based on multiple independent lines of evidence gathered during drilling, providing a robust early-stage picture of the reservoir:

• Drill cuttings containing gas-bearing sand grains physically recovered from the Hall formation
• Mud-log gas readings showing elevated hydrocarbon concentrations while drilling through the target interval
• Compositional gas analysis confirming the gas is biogenic in nature — 100% methane — consistent with the shallow Hall formation play type across the basin
• High total gas concentrations encountered throughout the target zone
• Seismic correlation: reservoir intersections correlate "almost exactly" with the pre-drill 3D seismic depth prediction, including direct hydrocarbon indicators (DHIs)

As of 6:00 am CET on 6 May 2026, the well was drilling ahead at a measured depth of 1,367 metres in 6⅛ inch hole. Due to ongoing gas shows encountered while drilling deeper, the well has been revised to a new total depth of at least 1,550 metres to ensure all gas-filled sandstones are fully penetrated.

"The Board of ADX is pleased and encouraged by the initial drilling results indicating that HOCH-1 is a gas discovery in line with our predrill expectations."
— Ian Tchacos, Executive Chairman, ADX Energy

Wireline Logging: The Next Critical Step

While the drilling results are highly encouraging, the immediate focus now shifts to wireline logging, planned for 7 May 2026. This programme will provide quantitative data on three key reservoir parameters:

1. Reservoir quality — porosity and permeability of the gas-bearing sands
2. Net reservoir thickness — the effective pay zone contributing to potential production
3. Gas saturation — the proportion of pore space occupied by gas versus water

A quick-look logging analysis will follow shortly after the logs are run. If the wireline results confirm the drilling observations, ADX intends to case and complete the well in preparation for production testing, which will ultimately determine deliverability rates and provide the foundation for formal reserves estimates.

Understanding the Hall Formation: Why This Reservoir Type Matters

What Is the Hall Formation?

The Hall formation refers to Miocene-aged (approximately 5–23 million years old) shallow marine and basin-floor sandstone channels deposited in the Upper Austrian Molasse Basin. These sandstones are known to be highly productive gas reservoirs across the region.

Why Does It Matter to Investors?

The Hall formation is not an untested geological concept. Nearby analogous wells within the same basin have recorded initial production rates of up to 9 mmscf/d (approximately 1,500 barrels of oil equivalent per day). This established production history from the same reservoir type provides meaningful context for what a successful HOCH-1 completion could look like.

Furthermore, the gas produced from Hall formation reservoirs is biogenic — meaning it is generated by microbial activity at shallow depths rather than from deep thermal processes. Biogenic gas is typically 100% methane, which is considered a high-quality, commercially valuable gas composition.

Glossary of Key Terms

Resource Potential: What HOCH-1 Could Deliver

The HOCH prospect carries meaningful resource potential. The following table summarises the unrisked recoverable prospective resource estimates for ADX's two permitted prospects in the ADX-AT-I licence:

ADX-AT-I Drill-Ready Shallow Gas Prospects — Recoverable Volumes (BCF)

ADX holds a 50% economic interest, so net attributable volumes are half the gross figures above.

At current European gas prices, the company notes that an 8 BCF discovery would generate in excess of EUR 120 million in gross revenue. ADX's 50% net interest in HOCH alone therefore represents material economic upside if the wireline and production testing results confirm the drilling results observed to date.

The High Case trap area for HOCH has been mapped at 8.2 km², with 3D seismic indicating a likely connection between the core P50 area and the northwest portion of the high-case upside.

The 2026 Drilling Programme: Three Wells, Three Opportunities

HOCH-1 is the opening act of a three-well programme ADX has permitted for 2026. The encouraging seismic-to-well correlation at HOCH-1 has direct read-across implications for the next two wells in the queue.

2026 Permitted Shallow Gas Drilling Programme

SCHOE is located immediately to the south of HOCH-1, and the two prospects are described as technically independent, meaning a result at one does not compromise the other. A combined HOCH and SCHOE success scenario could, consequently, enable a cluster development using shared infrastructure — including a single gas processing plant and a pipeline tie-in to the Upper Austrian grid, which sits just 2 kilometres from the HOCH drill site.

Beyond the 2026 programme, ADX has matured up to ten shallow gas prospects across the ADX-AT-I and ADX-AT-II licences, providing a substantial inventory of follow-up targets should the current drilling campaign confirm commercial potential.

Upcoming Catalysts to Monitor

1. Wireline logging results from HOCH-1 — expected imminently (planned 7 May 2026)
2. Quick-look logging interpretation — shortly after logging
3. Casing and completion decision — subject to positive logging results
4. Production testing programme — to confirm deliverability and support reserves estimates
5. GOLD-1 spud — next well in the 2026 programme
6. SCHOE-1 spud — third well in the 2026 programme

The Investment Case: Why This Result Matters

The ADX Energy HOCH-1 gas discovery in Austria is significant for several reasons that extend well beyond a single well result.

1. Seismic Prediction Validated

The near-exact correlation between the actual reservoir intersection and the pre-drill 3D seismic prediction is technically meaningful. It confirms that the seismic tools being used to identify and rank prospects across the portfolio are working as intended. This validation, furthermore, increases confidence in the mapped resource estimates for GOLD and SCHOE.

2. A Play, Not Just a Well

ADX has framed this as a shallow gas play with up to ten prospects identified. A single well result — particularly one that validates the seismic methodology — de-risks the broader inventory in a way that a more isolated prospect would not.

3. Economics Supported by Infrastructure Proximity

The project benefits from shallow drilling depths (keeping well costs lower), proximity to existing pipeline infrastructure, and current European gas pricing. The company notes these factors combine to support strong economics in a success case, without requiring long lead-time infrastructure development.

4. Near-Term Catalysts Are Stacked

With logging imminent, a completion and testing decision potentially weeks away, and two additional wells permitted for 2026, the news flow from ADX's Austrian programme is expected to remain active throughout the year. Each data point — logs, test rates, and ultimately reserves bookings — represents a potential re-rating event.

5. Established Analogues Provide Comfort

The Hall formation's track record of delivering initial production rates of up to 9 mmscf/d from nearby analogous wells gives investors a tangible benchmark for what a successful HOCH-1 completion might look like commercially.

Why ADX Energy Warrants Close Attention

The ADX Energy HOCH-1 gas discovery in Austria has moved the company from exploration concept to active gas discovery within its first drill result, with the added validation of seismic-to-well correlation providing a technical foundation that extends well beyond this single well.

The company enters the next phase of its 2026 programme with:

• A potential gas discovery at HOCH-1 pending logging and testing confirmation
• Two additional permitted wells (GOLD-1 and SCHOE-1) to be drilled during 2026
• Up to ten shallow gas prospects across two Austrian licences
• Established Hall formation production analogues demonstrating rates of up to 9 mmscf/d per well
• Cluster development potential with shared infrastructure between HOCH and SCHOE
• Pipeline infrastructure access within 2 kilometres of the drill site

Key Takeaway:

The ADX Energy HOCH-1 gas discovery in Austria has positioned the company as an active shallow gas explorer in one of Europe's established producing basins, delivering an early-stage result that validates its seismic-led approach. With wireline logging and production testing ahead, and two additional wells permitted for 2026, investors have a series of near-term data points to watch closely as ADX works to confirm the commercial potential of its Upper Austrian gas portfolio.

Want to Know More About ADX Energy's Austrian Gas Programme?

With gas encountered at HOCH-1, seismic predictions validated, and two additional wells permitted for 2026, ADX Energy is building what could become a significant shallow gas portfolio in the heart of Europe's established producing basin. To learn more about the company, its Austrian licences, and the investment case behind this emerging multi-well campaign, visit the ADX Energy website.