Boom and bust in US oil

Technological advances in the US have made it possible to extract oil at commercially viable rates from rocks that were previously inaccessible, unleashing a surge in production. But the industry has been a victim of its own success: oversupply has sent crude prices tumbling from their peak of over $100 per barrel last summer. The FT's Ed Crooks looks at how the oil industry of North Dakota is adjusting to be able to survive lower prices.