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Recent earthquakes in Haiti and Chile temporarily affected groundwater levels in Nebraska, University of Nebraska-Lincoln scientists say. Jesse Korus of the University of Nebraska checked a water well recorder near Aurora March 2 and found a little spike in the water level chart corresponding to the Feb. 27 earthquake in Chile. Korus also found another spike corresponding to the Jan. 12 earthquake in Haiti. The seismic waves’ effect on groundwater likely would have been missed if not for a decades-old instrument. The well contains a strip chart recorder, an instrument installed in the 1930s that uses pen and ink connected to a floating bobber. When the water surface moves, the motion is translated from the bobber to a pen moving along a strip of paper. When underground water levels change in response to earthquake activity, it’s called a hydroseism. Most equipment that measures groundwater in Nebraska is now digital amd is not set to continuously monitor water levels, and therefore are less likely to record hydroseisms, said Korus, the groundwater resources coordinator in UNL's Conservation and Survey Division, part of the School of Natural Resources. NU scientists want to do more studying of the connections between the quake zones and Nebraska’s underground water. Other major earthquakes also registered on the Aurora well equipment, such as the 2004 Indian Ocean earthquake and the resulting tsunami. But oddly, connected to the sand and gravel layers of the High Plains Aquifer, the Aurora strip chart recorder has recorded deep and distant earthquakes but missed local seismic events. "The significance is that this is something that needs to be researched," said Matt Joeckel, associate professor of geology in the School of Natural Resources and the Department of Geosciences. "Here in Nebraska it (the last two quakes) affected water levels in some wells," said Mark Burbach, associate geoscientist at SNR. "It is a reminder that what happens around the world affects all of us." And it’s a reminder that old technology can still work exceedingly well.
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