Advanced Seismology Studies
Jean Battaglia came to HVO from the Reunion Volcano Observatory in the Indian Ocean, as a Post Doctoral trainee. He worked to refine a technique for analyzing seismic signals in Hawaiʻi using spectral analysis of the seismic signals received at the various seismometers in HVO's network. His spectral plots consist of a matrix with 1440 lines (the number of minutes in 24 hours) along one axis and the frequency spectrum along the other. Under default background conditions, the entire spectrum is plotted in blue; but when an earthquake occurs, or harmonic tremor is detected, the frequency channels will "light up" in the plot with warmer colors reflecting higher amplitudes in discrete frequency bands of the spectrum. The results enable the seismic team to visualize, and analyze, the changing spectra of earthquakes or harmonic tremor.
Kass Ulmer worked as a seismic analyst, during the pandemic: "I primarily work on clearing a backlog of unreviewed earthquakes spanning the last ten years. I also respond to real-time events such as large earthquakes and seismic swarms."
Maddie Hawk is working with HVO analyzing earthquakes, using Jiggle, software developed to help review events. The P and S wave arrivals are picked automatically, but a reviewer (Maddie, in this case) adjusts them to be more accurate, and then uses the software to recalculate the location, magnitude, and depth of the event.
In the early 2000's,University of Hawaiʻi at Hilo graduates David Whilldin and Jason Meyer reinstalled a number of broadband seismometers around the summit of Kīlauea. These highly specialized three-component instruments are able to detect waves with amplitudes ranging from 50 Hertz to 60 seconds. In contrast, conventional seismometers pick up a much smaller band, typically from 50 Hertz to 1 second. The broadband instruments allow scientists to collect much more detailed information about the magma transportation system beneath and adjacent to Halemaʻumaʻu.