Figure 5
Taan Fiord tsunami deposits. The change in elevation between a 2014 DEM derived from satellite photogrammetry and 2016 lidar data reveals multi-meter changes in surface elevations of an alluvial fan reached by the landslide and swept by the tsunami (a). Where exposed in erosional banks or trenches, the deposit included a lower unit of very poorly sorted sand to boulders, and an upper unit of sorted boulders or cobbles (b,c,d - locations noted on map). At the trench in (b), and the outcrop in (d), the pre-tsunami surface was not exposed. However the outcrop in (c) extended down below the pre-tsunami surface, exposing siltier, browner sediment (contact dashed). Laterally, portions of the original soil was intact, and included shrubs folded uphill in the direction of tsunami inflood. Further down fjord, similar deposits were found where runup was about 50 m (e, contact dashed). Even where the tsunami had diminished to the point where runup was only 16 m, the deposit was still 40 cm thick and included abundant cobbles (f, contact dashed). Map in (a) created with QGIS 2.18 (http://www.qgis.org/en/site/).
