Oil- and liquids-rich natural gas plays marched to the forefront of drilling activity in the past year with the Niobrara, Eagle Ford and Bakken leading a 38% increase in active rigs from 684 active rigs a year ago to 947 rigs as of Jan. 7, according to a shale basin rig count compiled by NGI’s Shale Daily.

The rig count in the Eagle Ford in South Texas jumped 126%, from 53 to 120 and in the Bakken in North Dakota and Montana it went up 105% from 77 a year ago to 158 last week. The Granite Wash saw an 89% increase from 46 active rigs to 87. Active rigs in the Niobrara-DJ Basin in Colorado and southern Wyoming increased 200%, from 11 one year ago to 33 on Jan. 7.

The Marcellus rig count increased 47% over the past year, going from 95 active rigs to 140 on Jan. 7. The largest number of rigs were active in the Haynesville, although that play saw an 8% decrease year to year from 177 a year ago to 163 last week.

The massive move into the oil/liquids plays reflects the response to the wide spread between the higher oil and bottom-dwelling natural gas prices over the past year. The Arkoma-Woodford in Oklahoma registered a 19% drop and the tight sands Green River Basin in Wyoming saw an 18% decline during the same period.

The trends are illustrated in the first of a new weekly feature in NGI’s Shale Daily. Natural Gas Intelligence (NGI) has aggregated the shale basin rig data based on its own formula, using the basic weekly U.S. rig counts produced by Smith Bits, a Schlumberger company.

During the same year ending Jan. 7, 2011 drilling in the tight sands Piceance basin in western Colorado and Uinta in eastern Utah showed robust increases of 42% and 33%, respectively. The Cana-Woodford, in central Oklahoma, had a drilling increase of 36%.

The granddaddy Barnett Shale in Texas picked up just 7% in rig activity year to year, while the Fayetteville in Arkansas saw a 6% drilling decline.

The overall shale rig count showed a weekly decline of 22 rigs, going from 964 active rigs for the week ending Dec. 31, 2010 to 942 for the week ending Jan. 7, 2011 (see table).