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Field of View

Forties Alpha and the FASP drilling, really the feld’s story is around facility. Photo from Apache.

the portfolio growth, over time. When

Apache bought the feld, there were 38 of current production is from targets in the portfolio, he says. During

Apache-drilled wells.

the redevelopment, 153 wells have been

Apache has also broken drilled, including sidetracks, and there fow rate records on the feld. are still 63 in the portfolio, he says – the

In 2009, Apache fowed the target inventory keeps growing.

Charlie 6-3 well at an initial rate

Key to the target replenishment is of 10,500 b/d, the highest initial continued investment in seismic, Towart rate from a Forties well since says. The frst 3D seismic was shot over 1994. That record was broken the feld in 1988 – after 60% of the oil again in 2011, with Charlie 4-3 reserves had been produced. Apache shot reaching 12.567 b/d. more in 2005, 2010 and then 2013, with “What the drilling has the next 4D shoot planned for next year.

allowed us to do is create a late- Over the years, improvements in acqui- life production plateau of about sition technology and processing and 40-60,000 b/d,” Davenport interpretation techniques, have helped says, adding that many of these build a clearer map of the feld. “To make wells have been sidetracks, but 4D successful we are continually trying

Apache has also invested in to improve 4D processing and that’s

Drilling on Forties in the 1970s. Photo from BP.

downhole surveillance. really about noise levels and repeat-

This year Apache is drilling 14 wells, ability,” he says. The data had some the North Sea, which is remarkable given with 10 planned for next year. These will 30-40% noise in 1998-2000. That’s now that these are some of the oldest assets be drilled from the platforms and the been attenuated and is down to around [in the basin]. That has really been done

Rowan Gorilla VII heavy-duty jackup rig 7%, he says, through better repeatability through huge brownfeld investment drilling from the FASP. and matching. The better data is having from 2003-2009. To put it in perspective, if production capacity is 60,000 b/d and results at the drill bit. “We are fnding

Production efciency we increase effciency from 65% to 90%, success rates in the feld have climbed “It’s not all been about drilling wells,” that’s like adding 15,000 b/d to produc- from about 78% to about 90% in the

Towart continues. “There’s been a strategic tion. That’s adding value.” The investment last year,” Towart says, thanks to these focus on production effciency from early has also helped reduce lifting costs to 45% improvements. on. In 2013, production effciency was less than the average in the basin.

But, it also helps having a world- about 64% [around the current North Sea class reservoir, he says. Forties is a Late

Replenishing the inventory average]. That has been increased to more

Paleocene-aged turbidite channel complex

But, Towart says if some of Forties’ suc- deposited in a proximal submarine fan than 90%. In fact, in 2012-13, Apache cess can be characterized by aggressive location, with a high degree of complexity ranked No. 1 for production effciency in

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