In the face of falling oil prices, the number of onshore oil and gas rigs operating in New Mexico has plunged to 16 from 90 in just two years, a decline roughly in line with the national pace of rig reductions.

But data collected by IHS and shared with CNBC show that drillers are still prepping wells for production in the Delaware Basin section of the greater Permian, which lies beneath Eddy and Lea counties near the Texas line.

The average productivity for wells in the two counties has increased by about 50 percent from the beginning of 2013 through the middle of 2015, according to IHS analysis.

IHS estimates drillers can break even on the best wells in the Delaware when prices hit $38. U.S. crude futures have been trading between about $35 and $42 in recent weeks.