CREDIT AGREEMENT Dated as of December 22, 2004 among SOUTHERN BAY OIL & GAS, L.P. as Borrower, AROC OIL & GAS L.L.C., AROC RESOURCES L.L.C., AROC (TEXAS), INC., SOUTHERN BAY ENERGY L.L.C., SOUTHERN BAY LOUISIANA, L.P., SOUTHERN BAY LOUISIANA, G. P.,...