Understanding Ground Penetrating Radar Applications
When I left university I was rather excited about entering the world with my piece of paper. This degree showed I was trained in a specific field and was smart enough to know what I was talking about. At times, when around non-university graduates, I felt quite smug knowing I had something they didn’t. It was only when my boyfriend would come home and talk about his work as a geologist, or rather a geologist’s assistant, that I felt insanely ‘dumb’.
While I knew about Freud and Kinney, he knew about seismology and ground penetrating radars. He would sit at the table and explain these procedures to me in simple words, making me gaze in awe and loathing at his coolness. The ground penetrating radar was so intriguing.
This ground penetrating radar (GPR) is, as the name suggests, a means of penetrating the ground with several radars to determine whether or not an object is buried underneath the stone, ice or other structures. It also identifies any alterations in the material, and any voids or cracks.
But how? A question I found myself asking numerous times. Simple, he would say. The radar pulses image the subsurface and use high levels of electromagnetic frequencies to be sent into the subsurface. Ground Penetrating Radar QLD elaborates that; when and if the wave hits a buried object, crack or void then it will bounce back. However, the range of the electromagnetic pulse is measured on a spectrum and is limited by the conductivity of the ground.
I asked him again, what does he mean? He said that if conductivity is high, the penetration depth is low because the electromagnetic energy disappears into the substructure’s heat causing a loss of signal. However, if conductivity is low – like in ice – then penetration can be as high as hundreds of feet. This is because there is no heat.
GPR are easy to use, safe and more sophisticated than most methods in geology. I wish I had more access to them in my studies.