thumper truck

Three other thumper trucks were at work about half a mile ahead.

Essentially, thumper trucks come equipped with a large metal foot, which stomps on the ground.

The thumper trucks generate the sound waves.

They are using thumper trucks and doing a seismic survey to map underground layers and structures.

A thumper truck was stuck, tilted on its side, lodged precariously in the steep banks of a wash.

A thumper truck (or weight-drop) truck is a vehicle mounted ground impact which can be used to provide the seismic source.

We asked the land manager as politely as possible if he had the jurisdiction to redirect the thumper trucks from this riverbed to an already established seismic road to the south.

The thumper trucks create small earthquakes, and in many towns a small earthquake is discouraged for two reasons: 1) they are disruptive, and 2) they often precede fracking operations.

Oil and gas exploration is going on in the form of seismic tests - conducted with what are called thumper trucks - in sensitive wildlands adjacent to Arches and Canyonlands National Parks.

Last Sunday, with a group of friends all deeply concerned about the fate of this landscape, one of America's most treasured, I witnessed the destructive power of the thumper trucks on the fragile desert.

That's how one official described the activity of thumper trucks, though their actual mission is to engage in seismic testing to help drilling companies understand the makeup of the various layers of materials deep underground.

Up close, the thumper trucks creeping across the desert, following a path of fluorescent pink ribbons, looked like gigantic insects, gnawing and clawing, articulating right and left as they balanced themselves across the rugged terrain.

The thumper trucks and portable computer--- carrying seismic-survey vehicles had shown a progression of perfect underground dome formations in stunning abundance, some of them barely two thousand feet down, mere tens of vertical yards from the permafrost, and drilling through that would be about as hard as slicing a wedding cake with a cavalryman's saber.