Faults in Arctic sea ice radiate sound in the water, in the form of acoustic events, at two scales: that of individual cracks (small-scale) and that of faults and fracture zones (large-scale). In order to understand radiation of these mechanisms and their contribution to ocean ambient noise, in the aggregate, individual acoustic events were analyzed. Estimates of parameters that characterize particle motion and propagation of individual cracks were obtained. In addition, spatial and temporal event clusters were analyzed with the purpose to identify large-scale ice features. In regard to local motion of individual cracks, particle (local) displacement was in the range O( 10~(-4)) to O(10~(-2)) m, significantly lower than that of earthquake-induced faults and particle velocity was on average 50% lower than that of a displacement discontinuity in rock. Propagation speed estimates were in the range 100 to 1100 m/s, significantly lower than the Rayleigh wave speed assumed in previous studies. Tensile and shear fracture as well as coalescence of echelon arrays of secondary cracks, off large shear fractures were identified both in the low (10 to 100 Hz) and mid (100 to 350 Hz) frequency ranges.
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