If it is shallow, we could use an auger to get the answer, but sometimes using geophysics is also a nice way to find out. Our Mesas group reached the same conclusion and reserved the vertical electrical sounding (VES) equipment for a morning session between aggressive flies in their area. Although everybody used this equipment in the Twente field course, it is always difficult at first to find out how to connect all wires. In the picture shown below it is clear that everybody tries different strategies to come up with the correct answers.
|How to connect VES wires? Would drinking water help, or discussing the question in Spanish while looking at a bunch of wires, or is practicing yoga a better strategy?|
|Terrameter Valentina telling everybody to get their hands of the electrodes so that she can apply 2000 V to Mother Earth|
|EM34 measurement looking for Cretaceous clays below Quaternary sand|
Meanwhile, on the beach of Costa Nova, BSc students Evy and Leonie were still measuring water salinity on a mudflat. Now they used some real kind of industrial art, called a spiral auger (the Van Harlingen auger after its designer), to sample groundwater at different depths. The handle got stuck, was repaired, but now the thing starts at 3 m height, so they have to use the box to reach its top.
|Leonie and Evy sampling groundwater with the Van harlingen auger.|
|Sao Romao Group entering well data in their tablet computer.|