Royal Dutch Shell's third-quarter profits undershot analysts' forecasts on Thursday as a weak refining environment and production losses due to disruption in Nigeria weighed on its performance.
Third-quarter earnings excluding identified items and on a current cost of supply basis came in at $4.5 billion compared with a forecast range of between $4.9 and $5.1 billion and down from $6.6 billion a year ago.
Chief Executive Peter Voser, who steps down from the western world's number three oil company at the end of the year, said actions taken during the quarter "underline our commitment to shareholder returns", echoing an industry theme for the quarter as the sector underperforms the broader market.
World number one Exxon Mobil reports results later on Thursday.
The big drop in Shell profits was led by the significantly weaker industry refining conditions, that have been widely flagged by the company and others in the industry.
Rising costs in both production and finding operations in the main oil and gas division were also a major factor in the weaker results, along with production volume impacts from maintenance and asset replacement activities.
The fall also reflected the impact of pipeline outages in Nigeria, much of which Shell puts down to sabotage and theft, and lower dividends from a liquefied natural gas venture.
The Nigeria outage cost Shell 65,000 barrels a day worth of production. Total oil and gas output for the quarter was 2.931 million barrels of oil equivalent, down 2 percent on third quarter 2012 figures.
On the upside, Shell benefited from higher contributions from chemicals and increased underlying upstream production volumes, led by integrated gas.
Voser surprised investors by announcing an early retirement from his role earlier this year. He will be replaced by Ben van Beurden in January.