Continuing the downward momentum from the previous week (see Shale Daily, April 11), the number of rigs drilling for oil and gas in U.S. unconventional plays dropped by another 1% for the week ending April 15, according to NGI's Shale Daily Unconventional Rig Count.

The 963 rigs in operation during the week marked a six-rig decline from the previous week and a 20 rig decline from the previous month.

The largest week-to-week declines were found in the Haynesville/Bossier and the Granite Wash, which both declined by four rigs to 139 rigs and 87 rigs, respectively.

Amidst the declines, a number of plays eeked out small upticks in activity. The Bakken/Sanish/Three Forks (174), Barnett Shale (71), Eagle Ford Shale (166) and Niobrara-DJ Basin (6) all added two rigs each for the week.

NGI's Shale Daily Unconventional Rig Count utilizes county-level rig data provided by Smith Bits, a Schlumberger company, to more accurately target drilling levels in individual shale plays (see shaledaily.com).