The pace of drilling in Pennsylvania has declined by 35% in the first month and a half of 2013 compared to the same period in 2012, but counties rich in liquids and oil are faring better.

In January and the first half of February, 274 new wells were drilled, 98 fewer than in the same period of 2012, according to daily records maintained by the Pennsylvania Department of Environmental Protection.

NGI Shale Daily’s Conventional Rig Count indicates a slow-down as well. There were 105 rigs operating in the Marcellus Shale as of Feb. 15, down from 162 one year ago.

Of the 274 new wells added, 163 are unconventional. The new additions represent a 21% increase sequentially in new well construction over the last 45 days of 2012.

Lycoming County, in northeastern Pennsylvania, leads all counties with 30 unconventional wells added in 2013, compared to 43 unconventional wells over the same period in 2012. Two other northeastern dry gas counties showed significant activity, including Bradford County, with 22 new unconventional wells compared to 37 in early 2012; and Susquehanna County, with 16 compared to 26 in early 2012.

In the southwestern liquids-rich area, Washington County added 23 unconventional wells, off just one from the 24 drilled in early 2012; Butler County added 16, compared to 10 in early 2012; Greene County added 15, compared to 13 in early 2012.

Northwest Pennsylvania’s McKean County leads all counties with 36 new conventional wells drilled in 2013. All of its recent permits have been for conventional oil wells. Surrounding counties showed conventional oil activity as well. Warren County added 24 conventional wells in 2013, Forest added 14, Elk added 12 and Venango added 12 as well. That’s a total of 98 additional conventional wells (mostly oil) drilled in 2013, compared to 119 new conventional wells drilled in the five counties in early 2012.

Abarta Oil & Gas Co Inc. led all operators in early 2013 with 16 wells drilled in 2013. Anadarko Petroleum Corp., Arg Resources Inc., Alpha Shale Res LP and Armac Resources LLC each drilled 14 wells in 2013. Anadarko is based in Houston, the rest of the operators are based in Pennsylvania.