On a trading day that saw the S&P 500 gain 0.1%, the Energy sector (XLE) showed little change.

As a proxy for the sector, the ETF tracked closer to the overall market today than over the past month. Entering today's trading, XLE was up 5.7% over the last thirty trading days. The S&P 500, in comparison, went up 3.2%.

Ion Geophysical (IO) was one of the sector's big losers, as its price dropped 11.3% (-88 cents) to close at $6.89. 4.4 million shares of the stock moved. The stock traded between $6.54 and $6.98. Share price is up, having risen 12 cents (1.7%) from $7.01 on July 19, 2012.

Matador Resources (MTDR) was a significant gainer in the sector, rising 5.7%. The stock closed at $10.23 with 539,251 shares moving. The stock traded in a range of $9.67 to $10.31.

VAALCO Energy (EGY) fell 6% to close at $7.80, crossing its 50-day moving average of $7.90. Meanwhile, TransGlobe Energy Corporation (TGA) climbed 4.7% to close at $10.40, moving past its 200-day moving average of $10.27.

VOC Energy (VOC) rose 2.8% to close at $18.63, approaching its 50-day moving average of $18.75. It has also moved closer to its 200-day moving average of $20.15.

Alon USA Energy (ALJ) hit a new 52-week high today, reaching $12.82 to top the previous high of $12.49.