China National Offshore Oil Corp. (CNOOC) signed a production-sharing contract with Roc Oil (Bohai) Co. Ltd. and Smart Oil Investment Ltd. for the Weizhou 10-3W oilfield and Block 22/04 in the Beibu Gulf Basin of the South China Sea.

Under the terms, Roc Oil and Smart Oil will act as joint operator of the Weizhou 10-3W oilfield and Block 22/04, according to a July 3 news release.

Development operations in the Weizhou 10-3W field will be conducted according to each company's participating interests, with Roc Oil holding 35%, Smart Oil owning 25% and CNOOC having a 40% stake.

During the exploration phase of Block 22/04, all expenditures will be handled by Roc Oil and Smart Oil in proportion to each company's interest, which is 65% and 35%, respectively. Once the block enters the development phase, CNOOC holds the right to participate up to 51% in any commercial discoveries.

Subsidiary CNOOC China Ltd. will hold the rights and obligations under the contract except for those relating to CNOOC's administrative functions.

Roc Oil (Bohai) is a subsidiary of Roc Oil Co. Ltd., and Smart Oil Investment is a subsidiary of Sino Geophysical Co. Ltd.