Fig. 6

Horizontal hodograms for three consecutive fin whale notes recorded on seismic stations UGAL1, UGAL2 and UGAL4. (a, d, g) North–south seismic component (HHN) versus east–west seismic component (HHE) for the first 1 s of the first whale note in the black rectangle in Fig. 5. (b, e, h and c, f, i) show corresponding particle motions for the two subsequent notes in Fig. 5. The colour of each hodogram changes with time from black during the earliest part of each note, about 0.25 s long, to increasingly brighter colour, see time series shown in Supplementary Figure S8 for comparison. Coloured dashed lines represent back azimuth estimations, the resulting back azimuth range for each station is shown in Fig. 7. Vertical, north and east time series of the first note recorded at station UGAL2 are shown together with corresponding hodograms in Supplementary Figure S8.