CHEVRON <CHV>, NIPPON OIL FORM JOINT VENTURE Chevron Corp said its Chevron U.S.A. Inc unit and Tokyo-based Nippon Oil Co Ltd agreed to conduct a joint-venture oil exploration and development program on selected Chevron leaseholds in the United States. About 50 onshore and offshore exploratory wells will be drilled under the agreement and Chevron will be the operator of the project and pay some costs, the company said. It said Nippon will contribute an initial investment of more than 100 mln dlrs. The Japanese government will also participate in the venture by providing financing to Nippon through the Japanese Oil Corp, Chevron said. It said drilling will begin during the second quarter. Properties to be evaluated are located in California, Colorado, Kansas, Oklahoma, Mississippi, Montana, North Dakota, Texas, Utah, and Wyoming, along with Federal Outer Continental Shelf leases offshore Southern California and in the Gulf of Mexico, Chevron said.