Talisman Energy Inc., Canada's No. 5 independent oil explorer, said chief executive officer John Manzoni has stepped down, effective immediately.
The company said it named Hal Kvisle, former CEO of TransCanada Corp. and a director of Talisman, its chief executive.
The Talisman-operated North Sea oil platform Yme, under construction, had been evacuated in July due to problems with its substructure.
Mr. Manzoni, who held the top job for five years, had expressed frustration several times in the past year over what he called poor workmanship by Dutch contractor SBM Offshore, which has forced large portions of work to be redone.
Earlier, the company had written down the value of the project by $248-million. It had been on Talisman's books for $900-million.
Talisman said in June it would shift efforts to more valuable liquids-rich gas prospects as dry gas prices languished near 10-year lows.
Talisman, also known for assets in the North Sea, the United States and Southeast Asia, has been a potential takeover target following the $15.1-billion bid by Chinese state-owned CNOOC Ltd for rival Nexen Inc.
Shares of Talisman, which has a market value of $14.31-billion, have risen almost 28 per cent in the last three months. They closed at $13.87 on Friday on the Toronto Stock Exchange.