Two key operators have provided positive assessments of horizontal drilling results in the emerging Niobrara play in giant Wattenberg field in the Denver-Julesburg basin.
Anadarko Petroleum Corp. said its well results in the Niobrara and Codell formations indicate excellent economics and a net resource of 500 million-1.5 billion bbl of oil equivalent, and Noble Energy Inc. said its Niobrara activities have revealed an estimated net risked resource of 1.3 billion boe, up more than 60% from 2010.
Anadarko, producing from only 11 horizontal wells within field boundaries, said the company has 1,200-2,700 future drilling locations with estimated ultimate recoveries of 300,000-600,000 boe/well, 70% liquids. It put costs at $4-5 million/well. Initial well rates have averaged 800 boe/d.
Initial rate at Anadarko’s best horizontal well to date, the Dolph 27-1HZ, was 1,100 b/d of oil and more than 2.4 MMcfd of gas. The well paid out in less than 4 months, and EUR exceeds 600,000 boe. The play should become self-funding in short order because payouts are expected to average 10 months, Anadarko said.
At more than 70,000 boe/d, Anadarko is the largest net producer in the basin. It holds more than 350,000 net acres in Wattenberg and operates more than 5,200 wells with an average 96% working interest and 88% net revenue interest.
Anadarko will run extensive tests to define the optimum spacing and lateral lengths for the Niobrara and Codell. It plans to be running seven rigs drilling Wattenberg horizontal wells by the end of 2012 and drill 160 horizontal wells compared with 40 in 2011.
Anadarko said it is exploring other liquids-rich horizontal opportunities on its 550,000 net acres in the greater DJ basin outside Wattenberg and 360,000 net acres in the Powder River basin. Both prospective for the horizontal Niobrara and “other horizons that we will evaluate over time.”
Noble Energy said it holds more than 840,000 net acres in the DJ basin and expects to double its 2011 net production of 67,000 boe/d, 54% liquids, by 2016.
Niobrara horizontal drilling, Noble Energy said, has derisked the legacy portions of Wattenberg and has expanded the economic limits of the field by 67%. The company’s 58 horizontal wells in the Niobrara are yielding 14,000 boe/d of net production, up more than 20% since Sept. 30.
“Strong returns continue to improve with recent production performance exceeding previous results. The company’s most recent 18 wells are expected to achieve an average EUR of 355,000 boe, which is a 22% improvement over an average EUR of 290,000 boe from 23 early wells,” Noble Energy said.
Within 2 years, Noble Energy plans to double its horizontal Niobrara rig count and well completions.
