• Your EMAIL ADDRESS is never used for ANY purpose except to send you updates. EVER!!!!!!

    Join 1,214 other followers

  • MOUNT BAKER: Eruptive history, hazards, research.

    Visit Mount Baker Volcano Research Center websites Main website and the blog These are no longer actively maintained but are still good references [DT, April, 2020]
  • Most recent posts

  • This website first appeared December 6, 2009

    • 795,598 hits
  • Feel free to use the material on these pages.

    Creative Commons License
    This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 United States License.
    Northwest Geology Field Trips, by Dave Tucker, is licensed under a Creative Commons Attribution-Noncommercial- Share Alike 3.0 United States License. You can use what you find here, repost it with attribution to the author, "remix" it for your own purposes, but may not use it with the intent of making money off of it.

    EDUCATORS: Please feel free to use anything you find here that is useful to your mission educating people about Earth science. E-mail me if it would help to have a larger or higher-resolution version of any of the images. tuckerd at geol dot wwu dot edu

Martha Lake Erratic

By Greg Kulseth, and D. Tucker July 1, 2011; updated February 6, 2012, and March 20, 2012 with additional information from Bud Hardwick and Greg Kulseth.

Greg at the Martha Lake erratic and the new interpretive sign, March 2012. Compare with the graffiti-covered rock in 2011. Thanks to Snohomish County Parks for the cleanup! Photo courtesy G. Kulseth. Click to enlarge.

Getting there: From I-5 (north or south), take Exit 183 (164th St. SW) and travel east to Meadow Road. Turn left on Meadow Road and travel north to 146th St. SW. Turn right (east) on 146th St. SW and travel about 1000′ to the Martha Lake Airport Park entrance on your right (Snohomish County Park). You can’t miss the rock from the parking lot. But in case you do, the rock is at the edge of the woods to the east, at the NE corner of the soccer field near the covered picnic shelter. Coordinates are N47° 51.888′,  W122° 14.182′. There was geocache at this place, I’m not sure if it is still there.

The interpretive sign about erratics installed by Snohomish County Parks in winter, 2012.

The rock appears to be greenstone, a common type found in the lowlands. Photo courtesy Bud Hardwick.

The graffiti that had covered this erratic has been removed by Snohomish County Parks Department, and an interpretive sign about erratics has been installed.

Measurements and details from Bud Hardwick: The erratic is 40′ long, 15′ wide, and 18′ tall. From Bud’s photo and the general appearance of the erratic, the rock appears to be greenstone or greenschist, which is metamorphosed sea floor basalt. This is a common type of erratic found in the lowlands (see other examples of greenstone erratics at Coupeville and Langley, and Lake Stevens.

Greg at the Martha Lake erratic in summer, 2011. Lots o' graffiti. Photo courtesy G. Kulseth. Click to enlarge.

5 Responses

  1. Dave,

    I live in Shoreline, but I’d be happy to volunteer my time and energy to remove the graffiti from the Martha Lake Erratic if Snohomish park personnel or a volunteer group organizes a cleaning event.

    Greg Kulseth

  2. If said cleaning event happens on a Sunday or Monday not in August, I can devote some elbow-grease to the enterprise. Let me know!

    And for those wanting more photos, I have a few up here.. There will be more, including some with me not in the way, and some macros, as soon as I’ve caught up on other neglected adventures. If there’s an interest, I’ll post a link here.

    Thank you all for putting the word out about this erratic! It’s one of the neatest things I’ve seen, even with all the graffiti. Just marvelous!

    • Dana, and all,
      Thanks for offering. A clean up is getting organized by snohomish county Parks and volunteers. I’ll let you know the situation when I know myself.

  3. […] Kulseth reports this morning that the graffiti has been removed from the Martha Lake Erratic at Martha Lake Airport Park. The Snohomish County Parks Department also put up an interpretive sign […]

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: