(Image source: eaglerockenergy.com) Shares of Eagle Rock Energy Partners, L.P. (NASDAQ:EROC) are currently up 7 percent as a result of Regency Energy Partners LP (NYSE:RGP) acquiring their midstream business for $1.3 billion. Both companies are natural gas producers. The midstream business of Eagle Rock is located in Texas and consists of 8,100 miles of gathering pipeline and processing plants with the capacity to handle more than 800 million cubic feet of natural gas per day. The deal expected to be complete in the second quarter of 2014.