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    Visit Mount Baker Volcano Research Center websites Main website and the blog These are no longer actively maintained but are still good references [DT, April, 2020]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

Geology guide to Fragrance Lake Trail (Larrabee State Park)

The Christmas Girls had just finished decorating all the sign posts as I pulled into the parking lot. Very festive! Click to enlarge.

The Christmas Girls had just finished decorating all the sign posts as I pulled into the parking lot. Very festive! Click to enlarge.

I’ve written up a geology guide to the popular Fragrance Lake trail. You’ll find it here. Even if the hike is mostly in glacial till, there are interesting stones in it, and the Chuckanut cliffs are always worth a peak. I do some armwaving about the origin of the big cliffs above the lake, too.

Guided geology field trip offered: Rafting the Owyhee River in Oregon.

Ouzel Outfitters, a river guiding company in Bend, OR, is working with Dr. Kyle House (USGS) to host a 5-day Geology Rafting Field Trip through the lower Owyhee Canyon in south east Oregon.

The trip dates are April 19-23, 2013.

In the deep canyon, carved in rhyolite and basalt. Photo from Ouzel Outfitters.

According to Brian Sykes, proprietor of Ouzel Outfitters, highlights include hiking, photography, natural hot springs, an isolated river canyon, expert geology interpretation, and petroglyphs. Kyle House said this of the Owyhee: “This is possibly the most consistently amazing place that I have ever been lucky enough to work in. I will keep coming back…”.

The Owyhee canyon and the breached lava dams was the site of this year’s Friends of the Pleistocene field trip. The guide book can be downloaded here: https://sites.google.com/site/owyheefop/home/guidebook     (Bonus: you can also download the FOP songbook! Funny songs!)

I’ve included links below for information about this trip. Ouzel Outfitters provides this description of the geologic features on this trip:

“Between Rome and Birch Creek, Oregon, the Owyhee River passes through an astounding landscape born of a long series of geologic calamities. Among these are a series of massive, valley-choking lava flows; a nearly endless array of valley-flanking landslides; and huge flood-generated boulder bars that record the effects of catastrophic floods, landslide-dam failures and even the overflow of an ice-age lake that once sat in the Alvord Desert at the base of Steens Mountain. Over the last 2 million years, the Owyhee Canyon has been invaded by no less than six valley-filling lava flows. The lavas poured down its tributaries and over its canyon rim creating massive dams. Spectacular examples of the lava dams are abundant along this reach of the river, including towering cliffs of lava 100s of meters high; spectacular lava deltas that record the advance of the lava flows into large lakes of their own creation; and a series of ancient riverbeds below each lava flow that chronicle the Owyhee’s inexorable journey to the bottom of its modern gorge. The Owyhee lava dams were immense, some measuring 10s of kilometers in downstream length. At least some of them blocked the river for up to 20,000 years at a time. Once the Owyhee had filled the lakes with sediment and begun to carve its ultimate path around or through the dams, it generated huge landslides as it impinged on new valley walls, often resulting in landslide dams and short-lived lakes that failed catastrophically and moved huge boulders downstream.”

Camp scene on the Owyhee. Photo from Ouzel Outfitters.

Registration is limited to 14 people.  Kyle House and five river guides will give feel of a small personalized tour of fantastic geology, with one-on-one interaction and in-depth presentation.  If you register before the end of December, Ouzel is offering 2012 pricing.  In this case, the price would be $1029.00.

This page gives the quoted description above, plus a link to photos and a video:


This page provides details and reservation information for the field trip:


Rafts on the Owyhee. Photo from Ouzel Outfitters.

An abstract of a paper in the GSA Bulletin describing the lava dams is here:


and a geologic map is here: http://owyheeflotsam.posterous.com/

Online geology field trip: the Deadhorse Volcano, Skyline Divide, Mount Baker volcanic field

The last couple of miles of Skyline Divide. The Deadhorse Volcano is marked by the red pin and Hildreth’s unit designation ‘acr’. Click to enlarge.

A nearly unknown volcanic vent is exposed in cross section on a rock wall at the south end of Skyline Divide north of Mount Baker. Click here to read my on-line field guide to the informally named  “Deadhorse Volcano“. Yes, I know, winter approacheth, so chances to visit this eroded volcano are fast-slipping away. Hope for a weather break, or save this little gem until after the snow is gone next year. The snow that hasn’t fallen- yet.

Virtual geology field trip: Cougar Divide

Acres of flowers and meadows on the crest of Cougar Divide. Did I say I like this hike? The snow fingers mark the Dobbs Creek headwaters, site of many dikes. Copyright Dave Tucker.

I have broken out of my writing doldrums and written a self-guided geology field trip to Cougar Divide on the north flank of Mount Baker. Figure I better provide people with a summertime hike before it is too late! This hike is mostly volcanic geology that long predates Mount Baker. In fact, the oldest dated rock in the Mount Baker volcanic field is found on the ridge crest. That alone makes this beautiful hike significant.

Read the field trip here.

First MBVRC field trip of 2012

The first Mount Baker Volcano Research Center geology field trip of 2012 is announced over on the MBVRC blog.

The Pinus Lake lava towers 600′ above the Baker Highway east of Nooksack Falls. Click to enlarge any photo

The trip will head up the North Fork Nooksack and visit the Pinus Lake lava flow, the Wells Creek formation (subducted sea floor basalt), the gigantic Church Mountain Landslide, an older and larger version of the Racehorse Creek landslide, and Nooksack Falls. The trip will be led by Doug McKeever, geology Professor at Whatcom Community College. The first ten people have already signed up and the trip will reach its limit of 26 quickly so click here to  learn more about the trip and how to sign up.

Geologic hike on Sumas Mountain, Whatcom County: real geology and a mining hoax

Doug McKeever at the rusted ore cart and the infamous ‘gold vault’ from perhaps the biggest mining scam in the region. Photo courtesy Eric Rolfs.

Hey, take me straight to the field trip!

No, I haven’t finished my book. Time away from the keyboard is important, so what do I do? Go for a hike up Sumas Mountain, come home and write about the geology! I have had this field trip in my head for a while, and needed to share it. I did the hike back in early April with Doug McKeever and Eric Rolfs, but didn’t have my camera, so returned with Scott Linneman May 28. Click here to read the story of an audacious early 19th Century mining scam, and to learn about the geology on this short hike. You’ll also find a rare bonus- an exposure of the basal contact of the Chuckanut Formation, where it overlies the serpentinized ultramafite of Sumas Mountain.

Martha Lake erratic is all cleaned up!

Greg shows off the cleaned-up Martha Lake erratic. Spic and span! photo courtesy of Greg Kulseth. Click to enlarge.

Greg 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 about erratics: where they come from, how they get swept up into glaciers, and the extent of the last glacial maximum. The sign mentions the Lake Steven’s Erratic, and states that it may be the largest in the US.
Special thanks to David McConnell of the Parks Department, who, last I heard, was going to spearhead the cleanup, and to Greg for sending the good news.
I’ve updated the Martha Lake erratic webpage to show the now-cleaned up boulder.
Looking at my calendar, I see it is ‘Spring’. Looking out my window- hmmm. Oh, there’s a new snowdrop blooming, and maybe a leaf bud! Guess the calendar isn’t that far off, and the precession of the equinox marches on.

Have a good spring!

Coupeville’s Big Rock in the news

Big Rock. Island County Commissioner Angie Homola and her daughter Kira. Angie says she is 5 ft tall, so the erratic is about 22' (6.7 m) tall. 2010 photo by Dave Tucker.

Big Rock in the 1960s. Photo courtesy of Donn Charnley.

The big rounded erratic in Coupeville has recently been the subject of debate. The town council considered a proposal to purchase the land the erratic sits on to protect the rock from possible destruction. Their was concern that the owner of the apartments behind (to the west) of the rock would consider ‘removing’ the boulder to make room for a new and larger apartment complex. Here is the story in the Whidbey News Times. An earlier article in the paper, including information from UW glacial geologist Terry Swanson, describes the rock and the property ownership issue. The second article also reveals that at least as late as the 1930s, a stairway allowed access to the rock’s summit. Note that the newspaper refers to the big hunk o’ greenstone as ‘granite’, though a much earlier story in a rival newspaper (South Whidbey Record), identified the rock correctly in an article about erratics featuring Terry Swanson.

The Wedgwood erratic is on a lot cared for by the neighborhood.

Thanks to Valarie Bunn of Seattle’s Wedgwood neighborhood for supplying these links. She wrote about the similar Wedgwood erratic in her Wedgwood history blog.

Baker field guide published on line

For those of you who don’t subscribe to the Mount Baker Volcano Research Center website, here’s some news.

A field guide to Mount Baker deposits is available via link from the MBVRC site. The link takes you to a guide written by Dave Tucker and Kevin Scott for a Northwest Geological Society field trip in September, 2010. The guide describes Holocene lavas, lahars, and tephras in the Baker River valley, and the Pleistocene Kulshan caldera and Pinus Lava flow on the northeast flank of Mount Baker.

The trip guide is written by Dave Tucker (WWU) and Kevin Scott (USGS). The two-day trip was held in September 2010. It visited the Baker Lake side on Day 1- Holocene lahars, the Sulphur Creek lava flow, and tephras. Day 2 of the guide visits the volcano’s north east flank: Heather Meadows, the Kulshan caldera, and Pinus Plateau lava. The guide includes maps and color photos.

For a list of NWGS guides, go here.

New geology books

Two Eastern Washington field guides:

Washington’s Channeled Scablands Guide
, by John Soennichsen
Mountaineer Books, announced as available Mar. 1.


And, Described earlier on Northwest Geology Field Trips:

On the Trail of the Ice Age Floods, Vol. 2: The Northern Reaches by Bruce Bjornstad and Gene Kiver;

The first volume, by Bruce Bjornstad, is a very detailed and thorough treatment of the Missoula flood geology, focusing on the mid-Columbia basin

The Rocks Don’t Lie: A Geologist Investigates Noah’s Flood
by Dave Montgomery;
from W.W. Norton, due out in Aug. 2012

Dave is a geomorphologist on the faculty at the University of Washington.

I recommend: The Mountains of Saint Francis, (2009) by Walter Alvarez

This is a lay reader book focusing on the geology of central Italy. It has excellent descriptions of how geologists do their work, and the tools and methods used. It contains a great account of the discovery of the K-T boundary layer in the Gubbio Section of the Apennines this is the iridium layer that records the impact of the Chixhulub meteor marking the end of the Cretaceous, bringing about a frightful mass extinction. It describes the geooogy of Rome, and how it affected the rise of that civilization and great city. There is a copy available from the Whatcom Library.