Crazy Weird Erratics make National Natural Landmark Status!

Dave Tucker has a great web page http://nwgeology.wordpress.com/ (also on the Reading the Washington Landscape blog role) with field trips in our area that is well worth taking a look at for trip ideas and understanding the geology of our area. He describes several spectacular erratic rock locations in the area including some of my favorites and a few that I will have to visit. Thanks Dave, this post has been inspired by you.

Erratics are rocks that are out of place. Erratics have been transported by glacial ice to a new location where they are out of place. Erratics can be small, but the big ones seem to capture the imagination of geologists and non geologists alike. My wife Lisa describes the erratics on the Waterville Plateau in central Washington as “crazy, weird”.

I frequently look closely at erratics in glacial deposits on the Olympic Peninsula to determine if the glacial units I am looking at came from glacial ice from Canada or the Olympic Mountains. If I see granite, the odds are the unit was derived from ice that originated in Canada.

The Puget Sound, Strait of Juan de Fuca area and the northern tier of eastern Washington have all been glaciated multiple times over the past couple of million years. Hence, glacial erratics are a common feature in these areas. The most out of place erratics are the boulders that got rafted on ice bergs in the ice age floods that swept out of glacial Lake Missoula across eastern Washington and down the Columbia River. Several very out of place rocks can be observed in the Willamette Valley south of Portland from these flood rafted ice bergs. Erratic Rock State Natural Site is one spectacular example.

Erratic Rock Oregon State Natural Site (photo from Wikimedia Commons) 

Another great spot for erratics is the northern portion of the Waterville Plateau in central Washington. Part of this area has been protected under the National Natural Landmark program. Erratics make National Natural Landmark status! My wife Lisa and I love that area and some of the erratics have been the subject of a series of winter landscape paintings Lisa has done on the Waterville Plateau.

Winter Fields

 (Copyright Lisa McShane http://www.lisamcshane.com/Artist.asp?ArtistID=24358&Akey=G4YBGL8X)

Erratic and the Road

(Copyright Lisa McShane http://www.lisamcshane.com/Artist.asp?ArtistID=24358&Akey=G4YBGL8X)

Despite having observed many glacial erratics, I never get tired of seeing them and have a few favorites. While the erratic pictured below might not be the biggest, its position is crazy, weird.

Erratic ready to be cradled by Bob Bailey in case it falls out of glaical drift at shoreline northeast of Biz Point, Fidalgo Island, Skagit County.