Eagle Rock Energy Partners LP, Houston, (Nasdaq: EROC) plans to acquire certain fee minerals, royalties and working interest properties throughout the U.S. from Houston-based Montierra Minerals & Production LP, a portfolio company of Irving, Texas-based Natural Gas Partners VII LP and its affiliate NGP-VII Income Co-Investment Opportunities LP, for $127.6 million in cash and stock. The assets include interests in more than 2,500 wells on approximately 5.6 million gross mineral acres and 420,000 net mineral acres in 17 states. Net production is approximately 6 million cubic feet of gas equivalent per day. Net proved producing reserves are approximately 4.6 billion cubic feet of gas and 2.5 million barrels of oil.