Inside the riser pipe is a space about half a meter in diameter, large enough to hold the spinning drill pipe and bit and to allow the return flow of drilling fluid.

FORBES: The delicate art of sucking up

This swirling slows down the flow, and thus helps the fluid to cling to the surface.

ECONOMIST: The turbulent world of swimming

At that depth stopping the flow with a deadweight of drilling fluid should create few problems, once the exceedingly difficult challenge of hitting the well is met.

ECONOMIST: The Gulf oil spill

When the polariton flow was excited with two laser beams, the quantum fluid began to oscillate backwards and forwards in ways predicted by quantum mechanics.

FORBES: Watching Quantum Physics With The Naked Eye

On reaching the shale, the mixture of water and fracking fluid bursts open the rock and the sand keeps the fractures open, allowing the gas to flow to the surface.

ECONOMIST: Fracking