"I think the whole oil industry worldwide has recalibrated to a lower oil price level and shale is a lot more efficient." Yergin said at the World Economic Forum in Davos, Switzerland.
"OPEC now sees shale as part of the global mix," he added.
Yergin also responded to the recent deal between OPEC countries to limit oil production by 1.2 million barrels per day, or approximately 4.5 percent of current production.
While not perfect, he said he believed the deal would hold and would provide greater stability to what has been a hereto fractious relationship between OPEC members.
"It's really in the interest of these countries," he said.
"No OPEC agreement is perfect, but if there's large compliance it brings a sub-sense of stability. These countries were all looking at their budgets and needed to do something."