On the Gudrun field in the North Sea, Equinor and its partners have discovered oil and gas in wildcat wells 15/3-13 S and 15/3-13 A.
These were the 13th and 14th exploratory wells in production license 025. The Deepsea Stavanger rig was used for the drilling. The discovery's magnitude is estimated to be between 0.1 and 1.2 million standard cubic meters (Sm3) of recoverable oil equivalent in the Draupne Formation and between 0.4 and 1.3 million Sm3 in the Hugin Formation, according to preliminary estimations. The licensees will evaluate the well results in the context of local prospectivity. The main goal of the well's exploration was to find petroleum in Middle Jurassic reservoir rocks in the Hugin Formation and Late Jurassic reservoir rocks in the intra-Draupne Formation. Finding a reservoir in the Rødby Formation's Early Cretaceous reservoir rocks was the secondary exploration goal.
In the intra-Draupne Formation, Well 15/3-13 S came into thin strata of sandstone that contained oil. There was no contact between the water and the oil. The well found 92 meters of sandstone with subpar reservoir characteristics in the Hugin Formation. There were two instances of gas, each having a thickness of 8 and 7 meters. There was no contact between the gas and the water. The goal of drilling 15/3-13 A, a sidetrack, was to define the discovery. March 15, 2013 Intermittent sandstone layers with moderate reservoir quality made about 13 meters of the 85-meter thick oil discovered in the intra-Draupne Formation. It was established that there was an oil/water interaction 4328 meters below sea level. In the Hugin Formation, 15/3-13 A also revealed roughly 100 meters of sandstone with subpar reservoir characteristics. No evidence of gas/water contact was found, and the entire period was aquiferous. No reservoir was encountered in the secondary exploration target, the Rødby Formation in the Lower Cretaceous.
The wells were not formation-tested, but extensive data acquisition and sampling were carried out.
Well 15/3-13 S was drilled to respective measured and vertical depths of 4826 metres and 4740 metres below sea level. Well 15/3-13 A was drilled to respective measured and vertical depths of 4900 metres and 4814 metres below sea level. Both wells were terminated in the Sleipner Formation in the Middle Jurassic. The water depth is 110 metres, and the wells have been permanently plugged and abandoned.