Petišovci Project, Slovenia

Ascent is the Operator of the Petišovci Project which lies in the north-eastern corner of Slovenia on the borders with Hungary and Croatia.

Ascent holds a 75% interest in the Petišovci Project and its Joint Venture (“JV”) partner Geoenergo holds the remaining 25%. The current concession was awarded to Geoenergo in 2002 and is due for renewal in 2022.

Ascent has been involved in the project since 2007 and has spent approx. €50 million to the end of 2018. Ascent is liable for 100% of the costs and will receive 90% of the revenues until all costs are recovered.

Following a 3D seismic survey of the area in 2009, two wells, Pg-10 and Pg-11, were drilled in 2010/2011. Pg-11 was side-tracked for technical reasons, becoming Pg-11A.

These wells demonstrated that gas could be flowed in commercial volumes from previously unproduced (Pg-10) and previously undiscovered (Pg-11A) reservoirs. RPS energy performed an independent volumetric assessment of the field and verified P50 contingent gas resources of 456 Bcf.

Development of the field and bringing gas to market has been taking place in two phases.

Phase One: Export untreated gas to Croatia

  • Wells Pg-10 and Pg-11A were recompleted for production
  • Flow lines were constructed
  • Existing processing equipment was refurbished
  • A metering & pigging station was installed
  • The existing export pipeline was recertified
  • Untreated gas is being sold from Pg-10 and Pg-11A:
    • from April 2017, to a local industrial customer; and
    • from November 2017, export production to INA, Croatia’s leading oil and gas company.

Phase 1 is now complete.

Phase Two: Developing the field and selling gas into the Slovenian national grid

  • Increase production from Pg-10 and Pg-11A through the use of a compressor and, on receipt of environmental permits, re-stimulation
  • Re-enter and deepen 9 existing wells – permitting programme under way
  • Drill infill wells
  • Build a processing plant to treat the gas for injection into the Slovenian national gas network thus achieving the highest possible price – IPPC permit has been awarded by the Slovenian Environment Agency.

Further information can be found in the Reports and Presentations on this page and on the Investors Page. Please also see our RNS News & Alerts page for operational updates.


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3D Seismic Survey

In 2009 we conducted an extensive 3D seismic survey across the Petišovci area. This was the first ever 3D seismic acquired in Slovenia and required the agreement of over 10,000 landowners.

Interpretation of the seismic data provided a greater insight into the field structure and indicated zones of potentially better reservoir quality. The structure has two sets of reservoirs, the shallower Upper Miocene and the deeper Middle and Lower Miocene. The deeper Miocene reservoirs are Ascent’s main development objective and the locations of two new wells (Pg-10 and Pg-11) were determined.  The shallower reservoirs were developed during the 1960s.

The 3D seismic is now being reprocessed to increase our understanding of the remaining oil and gas volumes in the shallower zones and the prospectivity of the deeper pre-Tertiary Triassic basement.

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