Seismic Refraction

Before any new quarrying work takes place it is crucial to know the geology and depth to bedrock to ensure the viability of extraction.

Information on the extent of voiding, sedimentary structures and faults is also crucial to avoid unexpected quarrying difficulties that can result when these features go undetected.

Seismic waves are generated in the sub surface via a source such as a heavy weight drop or sledge hammer blow. These waves travel through the subsurface and are refracted from geological layers in the ground with contrasting seismic velocities. A line of geophones (ground motion sensors) detects the arrival time of the waves from source and their speed, this then informs geological layer thickness and composition.

SeismicRefractionChart.jpg

Applications for Seismic Refraction include:

  • Estimation of depth to bedrock
  • Fault/fracture detection
  • Hydrological Study
  • Landfill detection
  • Rippability estimation (the ease with which ground can be ripped by an excavator)
 

View the case studies using Seismic Refraction...

Seismic Survey on
Quarry Site