Transformation is underway in parts of the shale basins in the Lower 48 U.S. states following the discovery of a major oil play in Texas, Apache Corp. said.

After more than two years of testing and research, the company said it confirmed a significant discovery on the southern part of the Delaware shale basin in Texas that it dubbed Alpine High. Apache said it estimates in-place reserves of around 75 trillion cubic feet of natural gas and 3 billion barrels of oil.

John Christmann IV, the company's president and chief executive officer, said developing Alpine High is a core component of its strategy to bring value to shareholders.

"Our exploration success and financial results in the third quarter demonstrate the transformation that is taking place at Apache," he said in a statement. "Apache's extensive position in the play, which now totals 320,000 net acres, is an excellent example of our strategic focus on organic growth and strong technical capabilities."

Analysts cautioned that Apache might need a significant amount of infrastructure and will have to compete in a crowded shale playing field to advance with Alpine High. The company, nevertheless, said it's already drilled more than a dozen wells into the basin. Nine of those are already in production, though the company acknowledged volumes were limited because of infrastructure constraints.

The company reported net production from North American of around 270,000 barrels of oil equivalent per day, a level that represented more than half of its global output. It took a loss of $607 million for the third quarter but ended the period with $1.2 billion in cash, unchanged from the previous quarter.

Apache last year was the target of an all-stock takeover offer from rival Anadarko Petroleum Corp. Taking a multibillion dollar quarterly loss last year, Apache brushed off "rumors" of the bid, which Anadarko said was summarily rejected by the takeover target.