Crude oil production for Texas was up more than 20 percent year-on-year to just over 2.2 million barrels per day, a state regulator said.

The Texas Railroad Commission released preliminary figures for August, saying Wednesday production of 2.23 million bpd was up 24 percent from August 2013.

Total monthly production in August was 69.2 million barrels, up from the 55.6 million produced during August 2013.

Texas is the No. 1 oil producer in the United States.

Texas hosts part of the Permian shale basin, which the U.S. Energy Department said is the most prolific with average production of around 1.3 million bpd.

The Texas Railroad Commission adopted new shale rules, effective Nov. 17, meant to address disposal well operations in areas that may be prone to seismic activity.

Hydraulic fracturing operations have been linked to seismic tremors and commissioners said Texas was now taking the lead to ensure oil and gas operations in shale were safe.

"These comprehensive rule amendments will allow us to further examine seismic activity in Texas and gain an understanding of how human activity may impact seismic activity, while continuing to allow for the important development of our energy resources in Texas," Commissioner David Porter said in a statement.