"If you look at the WTI-Brent spread, and really look at where this crude is coming from in the U.S...as this production tries to find a home, it's certainly widening those spreads," the Marathon executive said.
Heminger added that the increased U.S. energy production from unconventional investment in alternative energy such as shale, as well as cheaper U.S. crude relative to Brent, should be a "catalyst for our earnings."
He also expects U.S. oil to flow into the Western Gulf of Mexico, where the company just acquired refining assets in Texas City, Texas from BP.
In its presentation discussing the purchase in October, Heminger said, "This refinery is located in one of the most diverse and liquid crude markets in the U.S., and is well-connected to logistics with access to the growing supply of Canadian heavy crude oil, as well as light sweet crude from unconventional plays in the lower 48 states." (Read More: The World's Biggest Oil Producers.)
The purchase will also balance Marathon's refining capacity "with a third in the Midwest, a third in the Western Gulf and the other third in Garyville, Louisiana," he told CNBC.
Marathon Petroleum has no plans to follow other companies and speed up its dividend payments or issue a special dividend. Many corporations have boosted dividends ahead of the looming "fiscal cliff", which may levy stiff new taxes on such investments if a deal to avert a raft of tax increases and spending cuts is not reached by year's end.
"We're going to stay with the same timing and sequence we've been in the past year to maintain our dividend going into next year," he said. "We don't see a special dividend heading into year end."