This map shows seismic speed in the Earth’s crust at 200 kilometers depth across the continental United States and portions of Central America and Canada. The North American craton (outlined in ...

This new-generation stress map of North America includes the first view of the style of faulting across the continent as well as more than 300 new measurements of the direction from which the ...

A map showing seismic speed in Earth’s crust at 125 miles depth across the continental U.S. and portions of Central America and Canada. The North American craton (outlined in black dashes) has a ...

North America is dripping—with ... are weakening the base of the crust. A map of the North American craton—outlined in black—as revealed by seismic velocity measurements.