Shutterstock photo In trading on Wednesday, shares of Extraction Oil & Gas Inc (Symbol: XOG) entered into oversold territory, changing hands as low as $10.28 per share. We define oversold territory using the Relative Strength Index, or RSI, which is a technical analysis indicator used to measure momentum on a scale of zero to 100. A stock is considered to be oversold if the RSI reading falls below 30. In the case of Extraction Oil & Gas Inc, the RSI reading has hit 28.9 - by comparison, the universe of energy stocks covered by Energy Stock Channel currently has an average RSI of 47.7, the RSI of WTI Crude Oil is at 52.3, the RSI of Henry Hub Natural Gas is presently 55.7, and the 3-2-1 Crack Spread RSI is 65.2. A bullish investor could look at XOG's 28.9 reading as a sign that the recent heavy selling is in the process of exhausting itself, and begin to look for entry point opportunities on the buy side. Looking at a chart of one year performance (below), XOG's low point in..