The key energy ETF gained about 1.4 percent, while the broader market inched up a little less than 0.3 percent.
In late morning trading, U.S. West Texas Intermediate crude futures hit a high of $51.90 a barrel, its highest level since Jul. 2015. U.S. crude later settled at $51.60 a barrel, its best settle since July 2015.
The sector is also the top performer so far in 2016, gaining more than 16 percent year to date.
— CNBC's Christopher Hayes contributed to this report.