01 May, 2012

Commingled Wolfberry a Clever Mix

Wolfcamp + Spraberry

 

Wolfberry isn't the latest flavor at the smoothie bar, but it may be the tastiest discovery in the past 50 years in the Permian Basin.

James Henry

Oil industry players have never shied away from creating new terminology.

Certain drilling targets in the Permian Basin are a good example.

Think Wolfberry, Strawberry and Wolfbone, for starters.

The trend here is to come up with catchy monikers for new plays, which really are a commingling of production from more than one formation.

The lower Permian-age Wolfberry, which is one of the hot items on the players’ current menu, is the designated name for the packed-limestone Wolfcamp and the overlying Spraberry sandstone combo.

Over the years, the long-productive Spraberry has acquired a reputation for guaranteeing long-term production that is at least so-so in essentially any location where it’s tapped.

Where the production is uneconomic, the Wolfcamp may sweeten the pot.

James Henry
James Henry

But it works both ways, according to James Henry, CEO and founder of Henry Resources LLC in Midland, Texas.

“As you leave the edge of the Midland Basin (near the Central Basin Platform), the Wolfcamp gets worse and worse, and the Spraberry gets a lot better in the middle of the basin,” Henry said. “But the Spraberry becomes worse on the basin edge where the Wolfcamp is economical.

“That’s why we drill both,” he noted.

Henry talked about his company’s experience in the play as part of the Discovery Thinking forum at the recent AAPG Annual Convention and Exhibition in Long Beach, Calif.

His talk was titled “The Wolfberry – How It Started.”

He should know: The Midland Basin has been his company’s turf-of-choice since 1971, when it began specializing in the Spraberry.

“It pays to stay in the same basin,” Henry asserted.

Close to the Edge

Henry noted the carbonate debris that came off the Central Basin Platform flowed into the Midland Basin. Toward the edge of the basin there were larger chunks of debris, and the lithology was more porous and cleaner.

In the middle of the basin there are more turbidites, mudflows and shales.

“After drilling 14 not-very-good wells, our geology department came up with the idea to drill close to the edge of the basin,” Henry said. “So we moved closer – and also used a new fracturing technique that our engineers came up with.

“In 2003, we drilled the Caitlin 2801 in the Sweetie Peck field in Upton County; it was the discovery well because it showed the concept that if you move closer to the edge of the basin, you get more production,” he noted.

“We included all of the Wolfcamp,” he added, “and not just the top and middle, as Arco had been doing.”

Henry credits the former Arco, or Atlantic Richfield Co., for the discovery.

“In the late ’90s, Arco began adding the Wolfcamp to the Spraberry,” he said. “They drilled about 300 wells in Midland and Upton counties and started trying different things, like different fracturing techniques.

Following BP’s purchase of Arco, Henry ultimately latched onto acreage through farmouts and such.

“We took a lot of what Arco pioneered and brought in a consulting engineer who worked for Arco and helped with the development of the fracturing technique out there,” Henry said.

“Arco was starting to figure it out when they got bought out, and they would have developed it,” he said. “We took it from there.

“We leased about 330,000 acres and have drilled almost 1,000 wells to date in the Wolfberry,” he said. “Additional wells have been drilled by other companies.”

The Price Is Right

There’s another key factor at work in this big play – the money.

“At the start of 2000, oil was about $20 a barrel,” Henry noted. “Because it went up, we could afford to implement these huge fracturing techniques where we’re fracturing these 10,000-feet-deep vertical wells with a million gallons of water.

“When this began, the cost to drill and complete a well was $700,000, and now it’s $1,700,000,” he said. “This is mainly due to increased costs, such as more fracturing stages and adding more Wolfcamp and other formations.

Plays such as this are a big deal for the players and for anyone who uses anything even remotely related to oil, i.e. everyone.

“There will be a million acres or more involved in this play,” he predicted. “If it’s all drilled out at 40-acre spacing, it should recover about three billion barrels of oil.

“The U.S. Geological Survey said it’s the largest discovery in the last 50 years in the Permian Basin.”

Henry gave kudos to Dennis Johnson, president of the company when they began pursuing the Wolfberry, noting how much he encouraged everyone.

In fact, the company’s engineering manager, the late Van Temple, coined the name Wolfberry in 2002.