In 2011 Dartmouth College’s Thayer School of Engineering sent a team to Greenland to study glacial ablation zones with a partner team from the University of Texas at Austin. A Scandinavian study undertaken a decade earlier focused on in-situ measurements and Dartmouth contacted GEOKON during their search for a similar monitoring method. Following a plant tour to better illustrate GEOKON's capabilities and product options, the Dartmouth team selected the Model 4600 Vibrating Wire Borehole Settlement System.

Once in Greenland, at approximately 69.5 degrees latitude, a 15 m borehole was drilled in the glacier icepack and the VW pressure sensor installed at the bottom, with the fluid reservoir installed inside a Campbell Scientific CR1000 Datalogger enclosure attached to a special frame positioned at the ice surface. Other weather station instruments were attached to the frame and also controlled by the CR1000. As the ice surface melted and sublimated, the distance from the frame and reservoir to the VW sensor decreased, thereby reducing the fluid column pressure on the sensor and accurately measuring the displacement due to the reduced ice mass. The system mimicked a typical soil settlement application where a VW pressure sensor is connected to bedrock and surcharge is placed on the surface where the settlement plate and reservoir are located.

The Dartmouth team left Greenland at the end of summer and shared the news of the successful research effort with us upon their return.