Woodside’s non-commercial well turns out to be swell for Quadrant

Drilling results from Woodside’s Swell-1 well offshore Australia have turned out to be encouraging for Quadrant Energy’s adjacent Belgravia prospect.

The Belgravia prospect, located within the Outtrim project in the WA-155-P(1) license, is adjacent to Woodside’s Swell-1 exploration well. Belgravia is operated by Quadrant with a 71.5 percent interest while Carnarvon holds the remaining 28.5 percent interest.

The Belgravia structure has a 45 square kilometer closure in water depths of less than 180 meters. It is approximately 20 kilometers southwest of and updip of the Swell Triassic prospect.

The Swell prospect is located within WA-483-P (Woodside 60% and operator, KUFPEC 40%), which neighbors WA-155-P(1). The Swell-1 well targeted an undrilled Triassic fault block some 20 kilometers west of the Nimrod Upper Triassic gas discovery.

In an announcement from late July 2017, before the spud of the Swell well, Carnarvon said that success of this well would greatly de-risk the Belgravia prospect and attract interest in the Upper Triassic play system in this region of the Northern Carnarvon Basin.

On Monday, January 22 Carnarvon referred to Woodside’s 4Q report released last week where Woodside had said that Swell-1 intersected interpreted gas sands across a large gross interval of approximately 450 meters. The well was announced as a tight gas discovery, not currently commercially viable given the low gas mobility at the depth the Triassic was drilled.

According to Carnarvon, this means that the Swell-1 well result is “encouraging in that it has confirmed the presence of a working petroleum system and contained a large gas column that was on the high side of Carnarvon geologist’s pre-drill expectations.”

Carnarvon’s mapping indicates the crest of the Belgravia structure is updip of the Swell gas discovery and around 650 meters shallower than the Swell-1 structure. Typically, reservoir quality typically improves at shallower depths, Carnarvon explained.

The company also said that Belgravia could contain better reservoir quality compared to that reported at Swell, but it also added that further work was required to fully consider the outcomes and opportunities arising from the Swell-1 well result, particularly in regards to the consequences for the Belgravia prospect.