The Selva onshore gas field is located in the Podere Gallina permit area in the Po Plain sedimentary basin, Northern Italy. The filed is being redeveloped targeting production start-up in 2020.
Po Valley Energy (PVE) is the operator of the Podere Gallina licence with 63% ownership interests, while the other licensees are United Oil and Gas (UOG) (20%) and Prospex Oil and Gas (17%).
The onshore gas field was originally discovered and developed by Eni. It had produced a cumulative total of 83 billion cubic feet (bcf) of gas during its 35 years of operational life, before it ceased production in 1984.
The redevelopment is considered to be a low-risk and high-return onshore gas development project. The field is estimated to contain 13.3bcf of gas in proven and probable reserves and is capable of producing 150,000m³ of gas a day.
Selva gas field location
The Selva gas field is situated in the Podere Gallina license, approximately 1km away from the Italian National Gas Grid, in the Po Valley region.
The Podere Gallina license area covers 331km² in the eastern part of Po Plain and lies south to the Po Delta. It is located 30km away from the coast in the Ferrara and Bologna provinces of the Emilia-Romagna region of Italy.
Selva gas field redevelopment background
The Podere Gallina exploration license was awarded to PVE in September 2008, while residual gas potential in the former Selva field was identified during an extensive geological and geophysical survey campaign carried out in 2012.
The Podere Gallina exploration license was certified to be containing 17bcf of contingent gas resources, during an independent evaluation in 2013.
United Oil and Gas (UOG) agreed to fund 40% of the cost of the first appraisal well on the former Selva gas field and, in return, acquire 20% stake in the Podere Gallina exploration license from PVE in May 2017.
The Podere Maiar 1 (PM-1) exploration/appraisal well was spudded in November 2017 and was declared as a commercial gas discovery in January 2018.
The production concession application for the Selva gas field was submitted in May 2018, which was approved by the Italian Government in January 2019.
Podere Maiar 1 appraisal well details
The Podere Maiar 1 (PM-1) well that targeted the reservoirs up-dip of the pre-existing wells of the former Selva field intersected two sandstone gas reservoirs named C1 and C2 of the Porto Garibaldi Formation.
The two reservoir structures were found to be delineated with a combined gross sand interval of 62m.
The peak flow rate in the lower reservoir C2 was recorded at 150,000m³, while that in the upper C1 reservoir was reported to be 150,000m³.
The well flow was also found to contain 99.1% methane gas content.
Selva field development details
The Selva gas field is planned to be redeveloped in phases, with the first phase involving two stages.
The first stage of the phase one will include the installation of a fully-automated gas plant at the existing PM-1 well site, while a 1km-long and 70bar gas export pipeline will be built in the second stage to connect the gas plant with the Italian National Gas Grid network, which is operated by Snam.
The Selva gas is expected to require minimal processing, due to its high methane and low liquid content.
The next phases of redevelopment will include drilling of additional wells in the Selva East, Selva South Flank, and Riccardina prospects.
CGG Services, a geological and petroleum reservoir consultancy based in the UK, provided the resource estimation as well as prepared the Competent Persons Report for the Selva gas field redevelopment.