Recent rapid growth in U.S. production of light tight oil has raised interest in understanding how U.S. refineries, many of which are configured to process heavier crude oil, might accommodate increased volumes of domestic light crude. The U.S. refinery fleet, which is distributed across Petroleum Administration for Defense Districts (PADDs) as shown in Figure 1, varies both within and across regions in capacity, quality of crude oil inputs, utilization rates, and sources of crude supply.
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