The Transocean Polar Pioneer, a semi-submersible drilling unit leased by Shell, was used to explore Arctic deposits. Photograph: Daniella Beccaria/AP
Shell folds in Arctic as Obama wins a big bet
Shell folds in Arctic as Obama wins a big bet
The Transocean Polar Pioneer, a semi-submersible drilling unit leased by Shell, was used to explore Arctic deposits. Photograph: Daniella Beccaria/AP
Preserve the Beartooth Front 
