The year-over-year improvement in segment contribution margin was attributable to increased margins at our El Dorado refinery and higher utilization rates at our Tyler refinery. In addition, we continued to benefit from our access to cost-advantaged domestic crude sources, such as Midland sweet crude, which traded on average $3.70 per barrel below the WTI Cushing benchmark during the third quarter of 2012.
Tyler, Texas Refinery
Total throughputs at the Tyler refinery were 60,589 barrels per day in the third quarter 2012, versus 59,812 barrels per day in the third quarter 2011. Total sales volumes were 62,467 barrels per day in the third quarter 2012, compared to 59,920 barrels per day in the third quarter 2011.
Direct operating expense was $30.9 million, or $5.37 per barrel sold, in the third quarter 2012, versus $29.4 million, or $5.33 per barrel sold, in the third quarter 2011.Tyler's refining margin, excluding intercompany product marketing fees, was $22.47 per barrel sold in the third quarter 2012, compared to $24.14 per barrel sold for the same quarter last year. This decrease is primarily attributed to higher crude oil prices compared to third quarter 2011. El Dorado, Arkansas Refinery Total throughputs at the El Dorado refinery were 69,757 barrels per day in the third quarter 2012 compared to 86,066 barrels per day in the third quarter 2011. Total sales volumes were 84,168 barrels per day, including 14,678 barrels per day of finished product buy/sell activities. This compares to 82,317 barrels per day of total sales volume in the third quarter 2011. Delek operated the refinery at 62,592 barrels per day of crude throughput during the quarter despite the continued suspension of crude oil deliveries from a supplier's pipeline, which has caused reduced throughput rates since May 1, 2012. The Company was able maintain this throughput level by using a combination of processing approximately 4,100 barrels per day of intermediate products from Tyler, and processing 11,550 barrels per day of crude supplied by rail.