Tuesday, May 26, 2015

Old Landslide Run Outs on Whidbey Island

I have been assembling some geology maps and landslide data and came across a couple of mapped landslide deposits on maps. The first was a map by the USGS of the Mukilteo Quad showing the dashed outline of a landslide extending well out onto the tide lands on the shoreline of Whidbey Island. 

Map by Minard (1982)

There is an image of this slide included in a map produced by Kueler (1988) on coastal erosion.  

1979 image of slide (Photo: Dave Frank, USGS #0128_59)

The deposit is now long gone and hence the landslide run out distance from the landslide off this bluff has been erased.

2014 Google earth image showing entire landslide deposit is gone from shore 

The Maxwelton Quad map (Deither and others, 1981) has a similar peninsula of landslide debris mapped onto the tidal area along the shore. Again no evidence of the slide deposit remain of this slide either other than the scar on the bluff itself.

Map by Dethier and others (1981)

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