LONDON — The financial impact of the sharp fall in oil prices has begun to show in the earnings of big energy companies.

Royal Dutch Shell, the first big player to post financial results since the steep decline in oil prices, said on Thursday that earnings in the fourth quarter of 2014 had actually risen from a year earlier, as improved performance in marketing and refining offset the effects of lower oil prices.

But the results were weaker than analysts had expected. A main culprit was that average oil prices in the quarter tumbled to about $72 a barrel, from about $95 a barrel.

Shell’s shares were down more than 4 percent in London on Thursday.

The financial picture for the sector should become clearer in coming days, as other major energy companies report results for the last quarter of 2014, which began with oil at about $95 a barrel but ended at about $55. On Thursday, the international benchmark, Brent crude, was trading at about $49 a barrel.