NEW YORK (TheStreet) -- Shares of Complete Production Services (CPX), Cobalt International Energy (CIE), Gran Tierra Energy (GTE - Get Report) and ReneSola (SOL - Get Report) made gains last week, while shares of First Solar (FSLR - Get Report), Superior Energy Services (SPN - Get Report), Chesapeake Midstream Partners (CHKM) and TransAtlantic Petroleum Ltd. (TAT) fell.Complete Production Services led the pack of winners last week, gaining 53.2%. Cobalt International Energy rose 26.4%. Gran Tierra Energy improved 25.3%. The company starts exploration drilling operations on two oil prospects in Brazil, as per International Resource News. ReneSola increased 23.8%. Other movers were Frontline Ltd. ( FRO) (up 23.0%), Oasis Petroleum ( OAS) (up 22.7%), Forest Oil Corp ( FST) (up 22.6%) and Denbury Resources Inc ( DNR) (up 22.0%).