D5202 - Seismic below 200 feet

Operational Details
In this industry employers may also use geophones, which is a line or several lines of sensitive receivers. Next they record the sound waves reflected back from rock layers after explosions or mechanical vibrations are created on the surface. Detonation of dynamite in shallow holes of less than 200 feet has been the traditional method. However, more recently, contractors use vibrioses, which is a system of using electrical discharges or compressed gas as the energy source. Deep well seismic surveys are useful where the rocks consist of alternating layers of different thicknesses and hardness, or where the rocks are folded or faulted into possible traps.

Geophysicists and geologists interpret the information and if required, map out a survey to be used in a drilling program.

The major difference between shallow (less than 200') and the deep well seismic work is that shot hole drillers, more or less, drill the holes for shallow well testing. However, the deeper well, or earth seismic studies, may result from a deep well drilling program, or from using explosives or other charges beneath the earth’s surface, as in an underground mine.

SIC Codes
000000375 - Seismic drilling below 200 feet