Firm said area could hold as much as 30T cubic feet of gas, or 5.5B barrels of oil equivalent.
Schlumberger said the combined company would have had pro-forma revenue of $59 billion in 2014.
The sale comes as sharply lower oil prices weigh heavily on companies in Canada’s oil patch.
The combined company will be the second-largest utility in the U.S. with a customer base of around 9 million.
The companies failed to provide sufficient data, so the merger review will resume following compliance.
Oil prices are under pressure, driven by a glut of oil in the United States and on world markets.
The Anglo-Dutch company is responding to an extended period of lower oil prices.
The roughly 40% fall in oil prices since last year is also sharply cutting into profits at BP.
WPX is trying to switch from pumping natural gas to finding new sources of oil.
The combined company would have a market capitalization of $21 billion.
Copyright © 2015. All rights reserved.