Vibrations of Arctic Sea Ice Near Utqiagvik, Alaska

Abstract:

This project studied vibrations of the arctic sea ice approx. 300m offshore from Utqiagvik, Alaska, in early March of 2020. Three-axis seismometers were constructed using SM-24 (SparkFun) geophones; the data from the geophones were collected with an Arduino Nano microcontroller. The tiny raw signals from the geophones were amplified with LT1677 operational amplifiers; their calculated amplification factor was ~2,700. The data were collected at ~140Hz and had the format (time, X, Y, Z), where “time” is the time since the sensors were turned on, and X, Y, and Z are the relative vibration amplitudes for each of the 3 axes. Data were collected in 2-to-3 hour blocks on several days, yielding over 5 million individual readings. We moved away from the seismometers immediately after starting the collections so our movements would not affect the data. The (Z) vertical sensor typically (but not always) showed the greatest amplitude; this could be from the sensors being better fixed to the ice vertically vs. horizontally. The data are analysed for vibration frequencies and dispersion, with implications discussed.