MOL makes oil and gas discovery in North Sea

MOL Norge, a Norwegian unit of Hungarian oil and gas company MOL, has made an oil and gas discovery near the Balder field in the North Sea offshore Norway. 

The Norwegian Petroleum Directorate (NPD) said on Wednesday that MOL had concluded the drilling of wildcat well 25/8-19 S and appraisal well 25/8-19 A. The wells are located in production license 820 S where MOL Norge is the operator.

The wells were drilled about 8 kilometers northwest of Ringhorne on the Balder field in the central part of the North Sea and about 200 kilometers west of Stavanger.

The primary exploration target for well 25/8-19 S was to prove petroleum in injectite sandstones in the Eocene to Palaeocene and in reservoir rocks in the Lower Jurassic (the Nansen Formation in the upper part of the Statfjord Group).

The secondary exploration target was to prove petroleum in sandstones in the Palaeocene (the Ty Formation), in reservoir rocks in the Lower Jurassic to Upper Triassic (the Eiriksson Formation and the Skagerrak formation) and in basement.

Exploration targets

In the primary exploration target, no injectite sandstone was encountered in the Eocene or Palaeocene. Water-bearing sandstone layers totaling about 45 meters with good to very good reservoir quality were encountered in the Nansen Formation.

In the secondary exploration target, water-filled sandstone layers totaling about 75 meters with extremely good reservoir quality were encountered in the Ty Formation. Oil-bearing sandstones totaling 6 meters with very good to extremely good reservoir quality were encountered in the Eiriksson Formation.

A 34-meter gas column in sandstone with moderate to good reservoir quality lies over an oil column of minimum 45 meters in sandstones with good to poor reservoir quality in the Skagerrak Formation. These sandstones total 22 meters within the gas and oil column.

The oil/water contact was not encountered. Weathered and partly fractured basement (under a basal conglomerate) are oil-bearing with a minimum column of 41 meters, but with poor to tight reservoir quality.

The well also encountered thin oil-bearing sandstone layers totaling 7 meters with good to very good reservoir quality in the Heimdal Formation.

The primary exploration target for appraisal well 25/8-19 A was to verify the reservoir potential in the Skagerrak Formation. The secondary exploration target was to perform a flow test in the Skagerrak Formation, to verify a petroleum column in the Eiriksson Formation, to investigate the upside potential in the Nansen Formation and to confirm reservoir in the Heimdal Formation.

In the primary exploration target, a total of 18 meters of gas and oil-filled sandstone layers with moderate to good reservoir quality were encountered in the Skagerrak Formation. No oil/water contact was proven.

In the secondary exploration target, the Nansen and Eiriksson Formation came in with water-bearing sandstones of about 50 and 30 meters respectively, mainly with good to very good reservoir quality.

A thin, oil-bearing sandstone of 2 meters with good reservoir quality was encountered in the Heimdal Formation, and which delineated the oil discovery in the Palaeocene.

The well also encountered thin gas and oil-bearing sandstone layers (injectites) totaling 8 meters with very good reservoir quality in the Eocene. The appraisal well also confirmed the oil-bearing basement, but with poor reservoir quality. No oil/water contact was proven in basement.

Extensive data acquisition and sampling have been carried out in the wells. Mini-DST (pressure and fluid samples) have been carried out in injectites in the Eocene, in the Heimdal formation, the Eiriksson Formation, the Skagerrak Formation and in basement.

A formation test has been performed in the Skagerrak Formation in the appraisal well. The test yielded maximum respective oil and gas production rates of 475 and 75,600 standard cubic meters (Sm3) per flow day through a 32/64-inch nozzle opening.

The formation test revealed moderate flow properties. Water was not produced during the test. Measured average GOR and oil density are 180 m3/m3 and 40 API respectively.

Preliminary estimates

Preliminary estimates place the size of the oil and gas discovery in the Skagerrak Formation between 2 and 11 million standard cubic meters (Sm3) of recoverable oil equivalent.

So far, no recoverable volume has been calculated for oil and gas proven in the other levels. The licensees will now evaluate the well results with regard to financial commerciality, further delineation and other prospectivity in the license.

These are the first and second exploration wells in production license 820 S, which was awarded in APA 2015.

Wells 25/8-19 S and 25/8-19 A were drilled to respective measured/vertical depths of 2737/2522 and 2927/2613 meters below sea level and were terminated in basement rock.

The water depth at the site is 126 meters. The wells have been permanently plugged and abandoned.

Wells 25/8-19 S and 25/8-19 A were drilled by the Deepsea Bergen drilling rig, which will now proceed to the shipyard at Ågotnes west of Bergen for periodic classification.