Pounding pavement: trucks sense geophysics

Trucks send seismic waves beneath cities to explore the terrain for oil, gas, faults and geothermal.

In 2017, two fleets of massive trucks crossed from Long Beach into Orange County in southern California, sending literal shock waves through the streets. And now, in Germany, they're going to be at it again.

The vehicle used to create these vibrations is a seismic vibrator truck or thumper. These t...