TAG finds oil-indicative mud gas
TAG finds oil-indicative mud gas
- Christine McKay
- 10th May 2013 7:57 AM
TAG Oil say early tests at its drill site on Ngapaeruru Rd, near Dannevirke, have shown elevated mud-gas levels.File
Elevated levels of mud-gas have been discovered at TAG Oil's Ngapaeruru-1 exploration well, 20km east of Dannevirke and the situation is encouraging, a company official says.
"We've had to increase the mud weights considerably as we drill deeper and we continue to see rising mudlog gas readings, including the oil-indicative C3-C5 factions, which is encouraging," Drew Cadenhead, TAG's chief operating officer said. "The 'oil kitchen' in these source rocks is definitely working below us. It promises to be interesting drilling over the next couple of weeks.
"We've successfully passed a couple of critical drilling challenges in the Ngapaeruru-1 well now, including cementing intermediate casing across the troublesome Weber and Wanstead formations. We can now drill confidently ahead into the Waipawa and Whangai source rock targets."
However, Mr Cadenhead said the significance of the elevated gas readings will not be known until wireline logs have been run and evaluated. The Ngapaeruru-1 well was spudded on April 22 and while the arrival of the drillers has met with opposition from local Frack Free Tararua and Lock the Gate groups, others in Dannevirke have welcomed the oil company.
"Yes, the oil industry should be regulated, but look at New Plymouth, it's booming. Why can't Dannevirke have boom times too?" Boz Charlton has said.
Protester Donald James of Weber told the Dannevirke News, he was worried at the prospect of a blow-out at the Ngapaeruru-1 well.
"I've heard the area is one of high pressure, which is good news for extracting oil, but it does add an element of risk," he said.
Mr James and his group are planning to keep the pressure on the Tararua District Council and will be making submissions to the draft annual plan.
"We've a lot of people who are going to make submissions because this is a major issue which can't be ignored,"Mr James said.
Meanwhile, TAG says the Ngapaeruru-1 well has reached an intermediate casing point at 977m with operations continuing according to the drill plan.
The planned total depth of the Ngapaeruru-1 well is approximately 1800m and is targeting the naturally fractured Waipawa Black Shale and Whangai source-rocks.
Horizons Regional Council gave TAG the go-ahead for its two wells, 1900m and 2000m deep, on private land at Mangahei and Ngapaeruru Roads, east of Dannevirke, in March.
TAG Oil chief executive Garth Johnson said his company was striving to leave the "smallest possible environmental footprint".
"These two wells are conventional vertical wells that will not be fracked," Mr Johnson said.