Looking Inside a Volcano
Dr. Phil Kyle and Dr. Daria Zandomeneghi, both from the New Mexico Institute for Mining and Technology, are trying to “CT” scan the inside of Mt. Erebus using active seismic waves. As a teacher, I have been invited to assist with the experiment through the outreach program funded by the National Science Foundation. Over the past few weeks the team has been installing temporary seismometers at specific locations on the volcano. These seismometers create a grid of stations that will record seismic waves from explosive blasts set off at various locations. The blasts will generate “active” waves in the ground. They are active waves because we will know the exact location and time that the waves are made. Knowing the time that the blast occurs will enable the researchers to look at the data from the seismometers and determine the location of the pipe and magma chamber inside Mt. Erebus.
We are currently installing the last of the over 100 seismometers that will be active during this experiment. Each seismometer is equipped with its own seismic sensor, a GPS unit for timing, and a battery with solar panel for power. The stations weigh 52 to 70 pounds each depending on the size of the battery. The lighter stations can be more easily carried and placed in locations that are more difficult to reach. After the stations are in place, holes will be drilled for the explosives. The holes will be up to 15 meters deep in ice. By recording the time that it takes for each station to detect the seismic waves and then matching that data with the locations of each station, a three dimensional map can be produced that will show what the internal structure of the volcano really looks like.