press release

Unocal updates earnings, production guidance in 10-K filing

El Segundo, Calif., March 15, 2002 - Unocal Corporation (NYSE: UCL) said it updated its 2002 earnings and production guidance in its Annual Report on Form 10-K filed today with the U.S. Securities and Exchange Commission.

In the 10-K, Unocal said it expects per share earnings of $1.40 to $1.50 for 2002. This compares with the previous guidance of $1.10 to $1.20 per share.

The forecast reflects lower dry hole costs and an increase in the expected average price for NYMEX benchmark crude oil. The guidance assumes an average crude oil price of $23.25 per barrel and an average North America natural gas price of $2.80 per million British thermal units (mmBtus). The price expectations are based on year-to-date actuals plus the NYMEX strip for the balance of the year. This compares with earlier expectations of $20.00 per barrel of oil and $3.00 per mmBtu of gas.

Pretax dry hole costs for the year are expected to range between $110 and $120 million. This compares with earlier guidance of $130 to $140 million.

The company noted that the positive factors would be offset by lower-than-previously-estimated production for the year. Unocal said it expects full-year 2002 worldwide oil and gas production will be about the same level as 2001, which was 504,000 barrels of oil equivalent (BOE) per day. Earlier, the company said it expected full-year 2002 production to average 510,000 to 520,000 BOE per day.

The revised production estimate is due principally to further declines in gas production in the Gulf of Mexico region, temporary well mechanical problems in Indonesia, and delays in license approval for new oil production in Thailand.

1Q 2002 guidance

Unocal said it expects per-share earnings of 10 to 15 cents for the first quarter 2002, unchanged from the forecast issued earlier.

The forecast reflects an increase in expected average oil and gas prices, offset by lower production volumes.

The first quarter guidance anticipates an average NYMEX benchmark crude oil price of $20.00 per barrel and an average North America natural gas price of $2.30 per mmBtu. The revised guidance compares with earlier expectations of $19.35 per barrel of oil and $2.25 per mmBtu of gas.

The company expects first quarter worldwide daily oil and gas production to average between 475,000 and 485,000 BOE. Earlier, Unocal forecasted production at 490,000 to 500,000 BOE per day for the first quarter. Production is expected to build from the first quarter levels through the year as new projects in Thailand and the Gulf of Mexico are brought on line.

Hedging update

Unocal has entered into costless collars on 25.2 million mmBtu of gas in the second and third quarters 2002 with an average ceiling of $3.31 per mmBtu and an average floor of $2.11 per mmBtu.

About Unocal Corporation

Unocal is one of the world's leading independent natural gas and crude oil exploration and production companies. The company's oil and gas activities are in North America, Asia, Latin America, the North Sea, and West Africa. Unocal is one of the world's largest producers of geothermal energy with operations in the Philippines and Indonesia.

This news release contains certain forward-looking statements about expected earnings, production, commodity prices, and dry hole and other costs. These statements are not guarantees of future performance. The statements are based upon Unocal's current expectations and beliefs and are subject to a number of known and unknown risks and uncertainties that could cause actual results to differ materially from those described in the forward looking statements. Actual results could differ materially as a result of factors discussed in Unocal's 2001 Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission. Unocal undertakes no obligation to update the information in this news release.

Investors are urged to consider closely the disclosure in Unocal's 2001 Annual Report Form on 10-K and other reports filed with the SEC (SEC File No. 1-8483). Copies of the company's SEC filings are available from the company by calling 800-252-2233 or from the SEC by calling 800-SEC-0330. The reports are also available on the Unocal web site.

Updated: March 2002