This trip through the geology of the Lewis River area involves about 2-3 miles of hiking. However, we will be driving about 120 miles total, so we encourage carpooling. Additional details and starting point TBA.

Field guide pdf can be found here.

Two Day Field Trip to Oregon’s Coast Range

Mary’s Peak, Sat. July 13

Join President Sheila Alfsen on a trip to the tallest point in Oregon’s Coast range. We will explore the rocks and geologic processes that made Oregon’s Island in the Sky. Participants will drive to Corvallis and carpool for the day-trip up to the top.

Hwy 20 from Corvallis to Newport, Sun. July 14

A tour along the newly constructed Hwy 20 from Corvallis to Newport. This one day trip will explore the fantastic road cuts of the Tyee formation of the Coast range. GSOC’s Clay Kelleher will show us the mitigation procedures that were employed to make this once unlucky and seemingly doomed highway a reality. Participants will gather at Ellmaker State Wayside near Blodgett to consolidate cars for the tour. 

$45 Registration fee includes field guide. However lodging and meals are on your own.

Register here.

Sorry this tour is sold out!

This is a Central Oregon Geoscience Society field trip.

This field trip will explore recent mafic volcanism in the McKenzie Pass and Santiam Pass areas, with a focus on the Sand Mountain volcanic field. We will look at recent lava flows and tephra deposits, and at rivers, lakes, and groundwater that have been shaped by volcanic activity. We will also discuss hazards associated with mafic volcanic activity, including forest fires, disruption of water routes, and damage to infrastructure, agriculture, and tourism. 

Our sister club Central Oregon Geoscience Society (COGS) has extended an invitation for this field trip to GSOC members. This offers a great opportunity for meeting fellow geology enthusiasts and for building ties between our two organizations. More information and registration on the COGS website.

Once again this year, Sheila Alfsen will host a tour by helicopter of Mt. St. Helens and the surrounding devastation area on Aug. 18, 2018. The price includes a presentation in the gift shop theater of the 1980 eruption and its aftermath, and a 40 minute flight over the devastated area and close up to the crater where you can see the effects on the landscape. Additionally Nathan Reynolds, Ethno-ecologist and Habitat Program Manager for the Cowlitz Indian Tribe, will be giving a presentation about the federal designation of Lawetlat’la/Mt. St. Helens as a Traditional Cultural Property of the Cowlitz Tribe and Yakima Nation. This event is sold out.

With cooler weather forecast for Saturday, ride with us along the Eastbank from the Portland's youngest rocks to its oldest. We will dine after at the Milwaukie Station Food Carts and Beer Garden. No geologic knowledge required.

This is a 3-hour moderately-paced bike ride (9 miles) with a return by MAX. (A shorter 5 mile route, with return by MAX, is also available.)  We will be starting from "Peace Sign Park" at NE Oregon and Interstate.

Sign-ups are now full. If you have already signed-up for this field trip with Dave Olcott, use the registration page to complete your registration and pay your registration fee. If you'd like to be on the alternate list, please email Dave.

The Geological Society of the Oregon Country will host a one-day helicopter field trip of Mt. St. Helens. The helicopter tour is approximately 40 minutes of spectacular scenery as you fly over both the devastated area from the 1980 eruption and the crater itself. An educational presentation by Sheila Alfsen will precede your tour so that you can recognize and interpret the landscape in light of the greatest volcanic event in recorded U.S. history.

This trip limited to GSOC members and their guests only. Become a member today! 

Registration now open. Limited to GSOC members and their guests only. This field trip, organized by GSOC President Rik Smoody, will focus on the geology of the Cascades and will climax in the total eclipse of the sun on the morning of August 21. It will be held at a private property in Mill City, Oregon, and will be limited to 48 GSOC members and their guests and 12 vehicles. Cost $80 per person. 

Join us for a one day field trip to study Missoula Floods gravel and cobble deposits, and Boring volcanism in Clark County on Saturday, June 17, 2017. Tour will be given by Bill Montgomery, CEMEX Executive, and GSOC Past Presidents Bo Nonn and Larry Purchase.

A One-day Field Trip

The Geological Society of the Oregon Country will host a one-day helicopter field trip of Mt. St. Helens. We will be based at Hoffstadt Bluffs Visitor Center on the North Fork of the Toutle River. The helicopter tour is approximately 40 minutes of spectacular scenery as you fly over both the devastated area from the 1980 eruption and the crater itself. An educational presentation by Sheila Alfsen will precede your tour so that you can recognize and interpret the landscape in light of the greatest volcanic event in recorded U.S. history.

The deadline for your payment is Thursday, Sept 29th, 2016. Click for tour and payment information. 

Registration now closed. Stay tuned for our report on the trip!

Our four-day excursion will travel down the coast to Brookings and across to Grants Pass before returning via I-5. The emphasis will be on the complex geology of the Mesozoic accreted terranes of the Klamaths but on the way we will take a look at Tertiary terranes of the north coast and interactions of Columbia River Basalt flows with coastal sediments.