Ms Bay has been vice president of exploration at Shell Exploration and Production Company since 2004. Prior to that, she worked at Kerr McGee Oil and Gas from 1999 until 2004. She was named vice president of worldwide exploration in 2002, and previously became vice president of North America Exploration, based in Denver, in 2001. She was named exploration manager of US onshore in 2000.

David Roberts, executive vice president of upstream at Marathon Oil, said: We are excited to have Annell join Marathon to lead our exploration program as we continue to pursue exploration growth opportunities around the world.

Annell possesses outstanding leadership qualities, as well as the technical expertise and broad industry experience to execute our strategy and to develop and further expand Marathon’s portfolio of exploration opportunities to the fullest potential.