One set of instruments that we will deploy on the glacier are seismometers, similar to those used to detect earthquakes. We have two different kinds, Refteks which will detect the higher frequency ice fracturing and cracking and 40TDs, broadband instruments detecting lower frequencies that will hopefully pick up rumbling from the waterflow within the ice.
The plan is to set the instruments out in a way that allows us to locate the source of the signal within the ice. For this to be successful we first need to check that all the instruments are all recording in the same way, this is known as a huddle test.
We have 8 Refteks, all mounted onto paving slabs and three broadband 40TDs encased in concrete based plastic tubes that will be drilled into the ice.
Ideally both systems are deployed level and we are assuming that they remain that way. However, as the following morning nicely demonstrated that will not be the case and so we will compare the data over a few days to see the effect this has. On the glacier we will bury the geophones (yellow box) below the surface snow/ice but do expect this to melt over the season.
The Refteks were setup and test relatively easily and we hesitantly moved on the 40 TD, there are only 4 of these, how long could it take?
We were expecting the 40TDs maybe a more challenging to set up and collect meaningful data and we later found that the internal mass of one had become stuck in transit. As a last-ditch attempt we gave it to Goldie to drive around in the cab of the forklift for a while but it wasn’t to be and four became three! All was not lost though and this curious Adelie Penguin was certainly pretty intrigued!