An Oklahoma-focused oil and natural gas producer has changed its name and beefed up its expansion plans after securing a cash infusion from private equity TPH Partners.

With the financial backing, Oklahoma City-based Harding & Shelton Exploration LLC (H&S) has become Antioch Energy. Plans are to build the asset base, reinvest in the current portfolio and double the nine-member workforce, founder Nathaniel Harding said.

H&S, privately held since it was formed in 1983, today has operations in 10 western Oklahoma counties. The go-forward strategy is to acquire and develop conventional and unconventional properties, still primarily in Oklahoma. The equity deal makes Antioch “significantly” capitalized, Harding said. Although the financial details were not disclosed, he called it the “largest commitment we’ve had in our history…”

Houston-based TPH, the private equity arm of Tudor, Pickering, Holt & Co., said the investment fit the bill after meeting Harding and CEO Kevin Dunnington.

“We had been looking for a quality Midcontinent team for quite some time, and when we were introduced to Kevin and Nathaniel we knew that’s what we had found,” said Managing Director Curt Schaefer.

Antioch already is “in the process of leveraging its deep relationships to begin acquiring new assets, and it is anxious to exploit the upside in its existing properties as well,” Harding said. The partnership should enable the company “to grow through both acquisition and further development of our existing assets,” Dunnington added.

“Everyone on our management team has run their own independent oil and gas company and brings a tremendous amount of experience, technical expertise and knowledge to the table,” Harding said. “Add to that TPH Partners…and we feel we are extremely well positioned for future success.”

TPH Partners has a long list of investments across the upstream, oilfield and midstream sectors. In June it formed EnWater Solutions LLC by combining its existing water business in the Permian Basin and assets acquired from Pelagic Water Systems LLC. Other investments include Pittsburgh-based Laurel Mountain Energy LLC, which acquires and develops oil and gas properties across the Appalachian Basin. Denver-based investments include Elk Meadows Resources LLC, which works in the Permian and northern Rockies, as well as Channel Energy LLC. Texas explorers with TPH backing include Principle Petroleum Partners LLC, Clearfork Resources LLC and Storm Peak Energy LLC.