Tuesday, December 25, 2012

Stories in the bluffs

To understand the coast, at least in this part of the world, is to understand the soft, easily eroded bluffs that back much of the shoreline. I had the chance to stop by Port williams in Sequim Bay the day before Christmas Eve and, as is often the case while wandering beaches around here, i found myself awestruck by the bluffs. Two things in particular struck me about this site...first, the incredibly complex stratigraphy that given the interpretation of a better observer would have told stories that, I suspect, would go back at least a few million years. Second, this was one of the few places that I've actually seen "erosion notches" recorded in the base of the bluff...these notches are produced by high water and wave action eating away at the base of the bluff and are one of the hypothesized mechanisms of bluff failure...but I haven't really seen them anywhere else. So here are a few pictures from the walk:

A view looking along the bluff back (south) towards the Port Williams boat ramp

Look at that stratigraphy! McHenry for scale.

Notches cut into the base of the bluff...likely a product of the persistent high water of winter combined with wave action generated by the east wind we've been seeing a a bit of lately.

Okay, someone help me with this one. In places where there were pockets of well-sorted sand in the bluffs there were these things...clearly organic, parchment consistency...what are they?

Here they are in situ

a view seaward towards Protection Island from the site.

No comments: