Online in December 2018; in print in the February 2019 issue
Our dynamic Earth is scattered with cracks. Earthquakes and petroleum fracking make cracks in rocks underground; melting ice forms cracks in glaciers. Freeze-thaw, roots pushing into weathered rock, the shatter from an impact—all these processes create cracks.
The details of the fracturing process remain a mystery. Scientists know that the roughness of a rock or ice surface can affect how fluids flow across it and how fractures travel through it. But what if you had a detailed 3-D movie of fractures in the act of forming, crack by crack?