Petrohawk Energy Corp., Houston, (Nasdaq: HAWK) and KCS Energy Inc., Houston, (NYSE: KCS) plan to merge into an onshore oil and gas producer with an enterprise value of approximately $3.7 billion. The combined company will remain known as Petrohawk Energy and headquartered in Houston. On a pro forma basis, Petrohawk will have estimated proved reserves of approximately 1 trillion cubic feet of gas equivalent of which approximately 68% would be classified as proved developed and approximately 82% would be gas. KCS stockholders will receive $9 per share in cash and 1.65 shares of Petrohawk stock for each KCS share, a consideration of $31.41 per share. Following the transaction, KCS stockholders will own approximately 50% of the company. The transaction concentrates Petrohawk in the east Texas and north Louisiana onshore Gulf Coast and the Permian and Anadarko-Arkoma regions. Floyd Wilson will remain chairman, president and chief executive, KCS's James Christmas will be vice chairman and William Hahne will be executive vice president and chief operating officer. The company will have nine directors, five nominated by Petrohawk, and four nominated by KCS.