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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

Book talk- Geology Underfoot in Western Washington

GUWW cover

Next book presentation by Dave Tucker*:

Camano Island Library

Saturday, April 21: 10:00am – 12:00pm

848 N. Sunrise Blvd., Camano Island, WA 98282

Directions here.

*Yes, alive and well.

Snohomish and Tacoma Geology Underfoot Book talks

A reminder that I will be in Snohomish this Saturday, Feb. 20, and in Tacoma next Thursday, Feb. 25, to talk about Geology Underfoot in Western Washington.

SNOHOMISH Saturday February 20th, 2 PM, Sno-Isle Public Library, 311 Maple Ave., Snohomish, WA

TACOMA Thursday February 25 Kings Book Store, 218 St Helens Ave Tacoma, WA. 7 PM http://www.kingsbookstore.com/event/2016-02

 

Washington interactive geology map

I get a lot of emails asking about on-line geologic maps. The Washington State Department of Natural Resources has a great resource. It is the Washington Interactive Geology Map. It allows you to select map scales, map background (topographic? street map? terrain?) and the type of geology you are interested in (faults? surface geology? tsunami inundation zones? landslide? volcanic vents?). You can play with scales and move around on a map of the entire state. The portal is here, which connects you to several interactive maps: http://www.dnr.wa.gov/ResearchScience/Topics/GeosciencesData/Pages/geology_portal.aspx

If you choose the Interactive geology map, you end up here: https://fortress.wa.gov/dnr/geology/?Theme=wigm

The menu lets you select lots of features to turn on or off. You have to play with it a bit to get it really

screen capture of a portion of the interactive geology map.

screen capture of a portion of the interactive geology map. Click to enlarge.

figured out, but it isn’t difficult. The figure above shows the screen set for western Whatcom County. In this menu I selected ‘surface geology’, 1:24,000 and 1:100,000 scale geologic map overlays. 1:24,000 scale maps are only available for some areas, and show up in the image as an area with denser information; an example is in the center, and lower left. You can zoom in on those for more detailed geology. You can turn text labels for geologic units on or off to reduce clutter. The more data you request, the slower the system is to load. I also clicked the box for ‘seismogenic features’, which turned on the blue dashed diagonal faults on the left edge of the screen.

Interactive map showing mapped faults in wesern Whatcom County.

Interactive map showing mapped faults in wesern Whatcom County. Click to enlarge.

This figure shows a much simplified view of seismogenic features only, in the same area. There are several fault strands in the Kendall area at center, as well as the same three faults between Gooseberry Point and Blaine. All the other information is turned off for clarity.

REQUEST TO READERS. If you experiment with any of the other interactive maps on the portal page (tsunami inundation zones, coal mine inventory map, natural hazards, seismic scenarios, etc. please consider writing a comment below about how useful you found it.

Glacial erratic inventory website open for business

White Rock, Hood Canal. Not in the inventory yet. Many of the erratics on the Northwest Geolgoy Field trips website aren't listed (yet). Maybe that is your job!

White Rock, Hood Canal. Not in the inventory yet. Many of the erratics on the Northwest Geology Field Trips website aren’t listed (yet). Maybe that is your job!

The Washington Glacial Erratics website has re-opened for business. Managed by the undergraduate GeoClub within the Earth and Space Sciences Department at the University of Washington, it is an inventory database and map showing “significant erratics (i.e., large, diameter >8-10 feet , or has a unique composition or features)” in Washington State. Anyone can add their favorite glacial erratics including photos and a description. You will need to know coordinates (UTM or Lat/Long). Visit the website at http://waglacialerratics.ess.washington.edu/ At present (February 9, 2014) there are 12 erratics shown. Get busy!

Dave Tucker

Google Earth Washington Geology Map program

Google Earth screen shot showing Skagit County, Washington, geology

Google Earth screen shot showing Skagit County, Washington, geology. Click to enlarge any image. The Eocene Rhyolite place mark is my own.

Google Earth (GE, download it here) can be a great tool for looking at landforms. Washington State’s Department of Geology and Earth Resources has prepared a set of 1:100,000 geologic map overlays for the state’s counties. Find them here. Scroll down to the very bottom of the webpage to find “Google earth 1:100,000 scale Surface Geology 3d overlays” . Download the kmz file, which automatically opens in Google Earth. The various geologic layers are listed in GE’s ‘Places’ menu. You can click the boxes to show, or hide, whichever aspect you are interested in. For instance, the default map units are opaque, and you can see no landscape through them. You can adjust the transparency of the overlay, or even hide the map colors (under the ‘geologic units’ submenu) so all you see are the welter of contacts. A tutorial video by DNR on YouTube explains usage of the Google Earth geology overlay. This uses the Whatcom county kmz file as an example.

The transparency slider.

Unit transparency slider: ‘Geologic units’ is highlighted, then click the blue box next to the magnifying lens, and tweak the slider.

The tutorial isn’t very clear on adjusting transparency, so I’ll go over that first. First, click the ‘geologic units’ box in the menu, then the blueish icon next to the magnifying glass at the bottom of the menu. Use your mouse to adjust the slider until you are happy, or at least reasonably satisfied.

GE Skagit geology, with unit polygons turned off. Lines are contacts and faults. Unit names remain.

GE Skagit geology, with unit polygons turned off. Lines are contacts and faults. Unit names remain.

GE Skagit county showing only occurences of Twin Sisters Dunite.

GE Skagit county showing only occurrences of Twin Sisters Dunite.

You may choose to use the menu to show only faults, or only unit labels, or only certain units. However, there may be a TON of map polygons associated with each unit, and each isolated occurrence of, say,

‘Darrington phyllite’ has its own box in the places menu. I’m still getting the hang of it. It is worthwhile to download one county’s geology .kmz file, and zoom out so the entire county is visible. Then you can click the various units listed in the expanded menu to see just what map unit, and where, that unit box belongs to. If you click on the name of a unit on the GE map screen, a balloon pops up with more, or less, information on the unit (see the figure below). Perhaps there will be only a tiny bit of information that is of little use, or maybe you’ll get lucky and get unit name, age, and even a reference. You can always rename units to make it easier to locate them in the places menu. Suppose you are interested in Darrington phyllite but only in the Blanchard Mountain area. You can find one of the mapped phyllite polygons on the GE image, click on the colored map polygon to see which label in the menu at left is highlighted, then rename that menu item ‘ Darrington SE Blanchard’ or whatever sort of personal label makes sense for your interests. You want to set aside some free time to play around with this program.

Burlington Hill (see page here on NW Geo FT blogs) with a unit clicked for info.

Burlington Hill (see page here on NW Geo FT blogs) with a unit clicked for info. Not all of the unit callouts will have this much information.

This is definitely a useful reconnaissance tool. These .kmz overlays take up a fair amount of space, so when you open GE you’ll need to be patient as they all load. The more county GIS layers you load into your GE program, the more slowly GE will open. You can always choose not to keep them in your GE Places menu, and access the maps from the DNR website each time instead. But then you have to tell GE not to save the overlay in the temporary places list when you close GE. Suit yourself. I use this tool a lot to help plan out field trips, so I’m the sort of person who would leave it loaded on GE in my computer.

Field guide to Iceberg Point (Lopez Island, San Juans) geology

Quartz veins crosscutting the sheared sandstone at Iceberg Point. As always, click to enlarge the photo.

White quartz veins cross-cut sheared sandstone at Iceberg Point. As always, click to enlarge the photo.

I have at long last published a new geology guide on the Northwest Geology Field Trips website. This one visits Iceberg Point, the beautiful and wild southwest tip of Lopez island out in the San Juans. Your visit to Iceberg Point requires a pleasant nearly-level stroll of around 2 miles (round trip). The geologic guide visits rocks sheared by subduction and accretion and the unconformity between those rocks and the overlying till. Plus, it just a great place for a day trip.

I have been distracted for months (years!) getting Geology Underfoot in Western Washington written and sent off to the editor. I visited more places for the book than I could submit to the publisher, and this is one of the ones I had to omit. It remains a great geo-trip. Wish I could have written more than one volume, but the publishers were having none of that. Sigh. So, I’m going to gradually put some of the ‘deleted’ book vignettes on this website. Thanks to all subscribers to this website; you have apparently been patient during this long hiatus. Don’t go away!

CLICK HERE TO GO TO THE ICEBERG POINT GEOLOGY GUIDE

Guided geology trip to Ptarmigan Ridge, Mount Baker

Mount Baker and Rainbow Glacier from Ptarmigan Glacier.

Mount Baker and Rainbow Glacier from Ptarmigan Glacier.

There are three spaces left on North Cascade Institute’s guided geology hike [led by yours truly] to the volcanic wonders along the Ptarmigan Ridge trail. This traverses the high country between Mount Baker and Artist’s Point at the end of the Baker Highway.

Sunday, September 29 Rendezvous in Glacier at 8 AM. An all day hike, about 6 miles round trip, 500′ elevation gain/loss. $95 includes bus from Glacier.

Sign up info here:

http://ncascades.org/signup/programs/mount-baker-the-story-of-volcanoes-ii-ph

Here’s the NCI blurb:

Experience time travel by foot on the Ptarmigan Ridge trail in Mount Baker’s radiant late-summer high country. Our field excursion will begin above tree line at Artist’s Point at the end of the Mount Baker Highway before venturing out toward the simmering, glaciated volcano herself. Along the way, we’ll travel over ancient records of volcanism as we traverse the 1-million-year-old Kulshan caldera, a giant volcano that erupted cataclysmically through a continental ice sheet long before Mount Baker built itself from stacks of lava.

As we hike past lava domes that erupted shortly after the caldera collapsed, we’ll lay hands on much younger columnar andesite that still predates Mount Baker, discuss the origin of the eroded table at Table Mountain, and examine layers of volcanic ash preserved in the soil, including the famous Mount Mazama/Crater Lake layer.

Dave is a leading geological expert on the Mount Baker region and will share his intimate knowledge of the natural and cultural history of the area. He’ll interpret the story of this landscape as evidenced in its rocks and ash.

Washington Erratics website temporarily down

Dear friends,

The new Washington Erratics website is temporarily down while a glitch is dealt with. Please do not send in new material until further notice. Anticipated reopening date is November 1. I’ll send out a post when the webmaster there gives me the thumbs up. http://waglacialerratics.ess.washington.edu/

Geology Underfoot in Western Washington- news about the publication date.

Dear friends,

News received here at geo-central today is that my geology guide book, Geology Underfoot in Western Washington, will be published in 2014 by Mountain Press Publishers in Missoula. Here is a link to the other books in the series. I have only three chapters yet to write: Johnston Ridge at MSH, Nisqually Vista at Rainier [deals with the consequences of rapid glacier recession] and the Introduction. Three others are currently in peer review by geologists who are authorities on those specific places. The MS should go to the editor around the end of February this year [I do have other things to do, believe it or not]. Thanks to all for the encouragement in this long process. Now that you know more about a publishing date [vague as it is] you can start saving your pennies to buy a copy or two; it should be a good gift.  Once the book gets through revisions, I’ll publish a list of the chapters, and hopefully more news on the publication date.

Here is a photo from the book.

Here is a photo from the book.

Here’s a figure from one of the most recent chapters.

What do you think it is about?

Pillows in the Middle Fork Nooksack

Stacked pillows. Stolen from a commercial website. So, sue me.

Stacked pillows. Stolen from a commercial website. So, sue me.

(Click HERE to go straight to the page about the pillows along the road.)

No, pillow lava, silly!

Cross-sectioned basalt lava pillow in the Elbow Lake Formation, Middle Fork Nooksack Road. Click to enlarge.

Cross-sectioned basalt lava pillow in the Elbow Lake Formation, Middle Fork Nooksack Road. Click to enlarge.

I planned a XC ski trip up the Porter Creek Road or elsewhere off the Middle Fork Road today, but it was raining and 41 degrees. Indulging my secret identity as a geologist, I instead poked around in a roadside quarry, looking at pillow lava in the Elbow Lake Formation. A rewarding outing from Bellingham if you have a 2-3 hours on your hands and a deeply felt need to look at some exotic, unusual, and (admittedly) not too beautiful rocks. The saving grace is the lava pillows, and a cup of coffee on the way and on the way back. As an added bonus, there is access to Twin Sisters dunite nearby.

P.S. There ARE some nice roads to ski up and back down off the Middle Fork.