Bellatrix Exploration said its chief executive has taken a leave of absence to focus on a personal medical situation.
Raymond Smith will be replaced by Brent Eshleman as interim chief executive in his absence.
Eshleman joined Bellatrix as executive vice president in July 2012 and became chief operating officer of the firm in 2014.
In a statement the company described him as a “seasoned industry leader” with more than 30 years of oil and gas industry experience.