Researchers explore how fractures nucleate, propagate and stop
Experimental system and properties of extended fractures. a, Top, experimental set-up showing a penny-shaped growing fracture with the fluid (blue) lagging the fracture front (red). Bottom, cross section of the fracture and injected fluid. b,c, Images of the fracture 2 ms (b) and 4 ms (c) after crack initiation. d,e, Kymographs from the edge of the injector in the north-east direction showing the amplitudes of the fluid front (blue lines) and fracture…