Updated from 9:25 a.m. EST

Three big oil companies posted lower earnings Thursday, hurt by weak results in their refining operations and in one case the turmoil in the wholesale energy trading business.

Royal Dutch/Shell

(RD)

posted an 8% decline in normalized third-quarter earnings, a slightly better than expected result, and affirmed its production outlook for the full year. The British and Dutch conglomerate said earnings, using a regularized cost basis and excluding items, were $2.4 billion, down 8% from a year ago but above the $2.3 billion analysts were predicting at the high end.

Prices for refined fuels such as heating oil and jet fuel have been hit by a weak economy and the slowdown in air travel.

The company told a conference call it's on track to meet its 2002 output target of 3.8 million barrels of oil equivalent a day. The shares were recently gaining about 3% in New York to $42.90.

Exxon Mobil

(XOM) - Get Report

said quarterly profit fell 17% to $2.64 billion, or 39 cents a diluted share, from $3.18 billion, or 46 cents a diluted share, a year earlier.

Excluding special items, the company's earnings were 44 cents a share. Analysts had expected the company to report a profit of 43 cents a share, according to Thomson Financial/First Call.

The shares were recently up about 0.2% to $34.15 on the

New York Stock Exchange

.

The worst off was

ChevronTexaco

(CVX) - Get Report

, which reported a steep loss in its third quarter after writing down is investment in troubled U.S. energy company

Dynegy

(DYN)

.

"We experienced oil and gas production disruptions in several areas and faced continued weak markets for refined products and chemicals," said Chevron chief executive, Dave O'Reilly, in a statement.

Chevron reported a loss of $904 million, or 85 cents a share, compared with net income of $1.3 billion, or $1.19 a share, in the year-ago period. Excluding special items, Chevron earned $1.17 share. Analysts were expecting earnings of $1.29 a share, according to Thomson Financial/First Call.

The company had $2.1 billion in charges in the third quarter, including a $1.5 billion writedown for its investment in energy trader Dynegy and $485 million for asset impairments. It also had $73 million in merger-related expenses.

At the end of the third quarter, Chevron said it had $412 million in Dynegy investments on its books.

On a conference call with analysts, ChevronTexaco said it saw a big jump in pension costs. Whereas the company had pension credits in 2000, it said costs were running $90 million a quarter, due to a weak equity market and changes in its actuarial assumptions

Formed a year ago by Chevron's takeover of Texaco, the company said it expects the merger to boost 2002 net income by $500 to $550 million.

Shares of Chevron were lately off $3.40, or 4.8%, at $68.