Field Trips

COGS offers a variety of field trips led by experts on Oregon's geology.


Geo-Explorations

Informal hikes, bike rides, and other explorations of geologically interesting sites.


To participate in field trips and geo-explorations:

  • You must be a member of COGS, or a guest of a member, to participate in field trips and geo-explorations.
  • You must sign the COGS field trip and geo-exploration waiver.
  • Please arrive at the meeting location 5-10 minutes early to get signed in.
  • Check the weather report and plan accordingly. Remember that weather conditions can change quickly in central Oregon! Dress in layers and wear sturdy hiking shoes.
  • Bring plenty of water and snacks, pack a lunch if specified in the field trip description.
  • Please leave your pets at home – dogs are not allowed on COGS field trips. 

    COGS Field Trip & Geo-Exploration Waiver


    Upcoming Field Trips

      • 9 Jun 2023
      • 9:30 AM - 5:30 PM
      • Biggs Junction, OR
      • 5
      Register

      OR State Parks, JackBrownPDX

      Columbia Gorge Field Trip

      Led by Bill Burgel

      Friday, June 9, 9:30 am - 5:30 pm


      Registration opens on May 24

      Please join Bill Burgel as we explore the Columbia River Gorge from Biggs Junction downstream to Troutdale.  After an orientation and overview from the rim, we will proceed downstream making numerous stops along the way.  Topics will include Columbia River Gorge Basalts, Missoula Flood erosional and depositional features and more recent geological events such as landslide and lahar deposits.  In addition to being a structural geologist, Bill worked for 50 years in the rail industry and will be available to answer any questions related to the two railroads operating through the Gorge. 

      This field trip will mostly involve driving from stop to stop with only minor amounts of walking involved.  To facilitate the logistics and parking, we will be trying to minimize the number of vehicles in the caravan.  There will be ride sharing meet up locations  in Bend and possibly points north for those interested.  As a reminder, ride sharing is completely voluntary and COGS does not directly organize this.

      Contact the field trip coordinator, Derek Loeb ( DerekLoeb@gmail.com ), with questions.

      Please note that this event is limited to 15 participants and registration must be done via the registration button on the trip listing on the COGS website.  Successful registration will be confirmed on the webpage by a light green box indicating registration was successful and by a confirmation email.  If you don't get this email you should try the registration process again.  If the trip is full, please join the wait list.



      • 24 Jun 2023
      • 9:30 AM
      • 25 Jun 2023
      • 3:30 PM
      • Hines, OR
      • 15
      Register



      Hank Johnson (L) and Dr. Steve Gingerich (R) at Barnyard Spring, western Harney Basin.                    Photo by  Derek Loeb

      Hydrogeology of Silver Creek Field Trip, Western Harney Basin

      Led by Hank Johnson & Dr. Steve Gingerich

      Saturday & Sunday June 24-25, 9:30 am - 5:30 pm


      Registration opens on June 8

      Please join hydrogeologists Hank Johnson and Dr. Steve Gingerich for a two day field trip exploring the hydrogeology of Silver Creek in western Harney County.  The first day we will make a series of stops to understand the recharge area of the aquifer system and the second day will focus on the discharge area.

      Silver Creek is a medium-sized intermittent creek in western Harney County with a big story to tell. One involving 170 million year old island arcs, cataclysmic caldera eruptions, continental-scale tectonic processes, and 8,000 year old groundwater. Its story is also a microcosm of the water management challenges writ large across the western US.

      This trip will follow Silver Creek from its headwaters in the Ponderosa forests of the Blue Mountains to its final destination in the wetlands and playas of the Malheur National Wildlife Refuge west of Harney Lake. Springs bookend the field trip, beginning with small-volume springs that feed upper Silver Creek and ending with large-volume thermal springs in Warm Springs Valley. The creek follows the Brothers Fault Zone for much of course as it flows across three major physiographic provinces: the Blue Mountains, the High Lava Plains, and the Basin and Range. We will explore how the complex geologic history of western Harney County has influenced the distribution of groundwater and surface water in the basin. And, how that distribution has influenced water resource management and development over the last 150 years.

      Participants will meet at Fastbreak Convenience Store/Eddies Truck & Auto Center (Sinclair) on the north side of U.S. Highway 20 on the western edge of Hines, OR at 9:30 AM.  The meetup location for the second day will be at the ODOT Sage Hen rest area on the south side of U.S. Highway 20 about 14 miles west of Hines.  Participants will be responsible for their own lodging arrangements.  The Hines/Burns area has numerous options including the historic Central Hotel or a Best Western.  There are also several camping options in town including the Burns RV Park as well as numerous other options in the surrounding area including public land.  It is also possible to commute to the area for the day.  This is an integrated two day trip, but those who can only attend for a day will be accommodated on a space available basis.  The logistics of caravaning and parking will be easier with a limited number of vehicles so opportunities to ride share for the day's itinerary will be available.  As a reminder, ride sharing is completely voluntary and COGS does not directly organize this.

      Contact the field trip coordinator, Derek Loeb ( DerekLoeb@gmail.com ), with questions.

      Please note that this event is limited to 15 participants and registration must be done via the registration button on the trip listing on the COGS website.  Successful registration will be confirmed on the webpage by a light green box indicating registration was successful and by a confirmation email.  If you don't get this email you should try the registration process again.  If the trip is full, please join the wait list.



    Past Field Trips

    24 May 2023 Smith Rock Geo-Exploration
    26 Apr 2023 Session 2: Riley Ranch Field Trip
    21 Apr 2023 Riley Ranch Field Trip
    31 Mar 2023 Session 2: COGS Geo-Exploration: Barnes Butte, Prineville, OR
    31 Mar 2023 COGS Geo-Exploration: Barnes Butte, Prineville, OR
    12 Mar 2023 Steelhead Falls Geo-Exploration - Session 2
    11 Mar 2023 Steelhead Falls Geo-Exploration
    26 Oct 2022 Mafic Volcanism!
    30 Sep 2022 Thomas Condon Paleontology Center tour and field work experience
    17 Sep 2022 Deschutes Formation and Tumalo Volcanic Center Field Trip
    24 Aug 2022 Melting Glaciers, Failing Dams: The 1966 Debris Flow from No Name Lake Field Trip
    5 Aug 2022 Faults in the Strawberry Mountains
    1 Aug 2022 Whychus Creek Geo-Exploration
    26 Jun 2022 Lava Cast Forest Field Trip
    4 May 2022 COGS Geo-Exploration: Gray Butte
    7 Apr 2022 COGS Geo-Exploration: Barnes Butte, Prineville, OR
    3 Dec 2021 COGS Geo-Exploration: Farewell Bend Loop
    1 Dec 2021 COGS Geo-Exploration: Flatiron Rock in the Oregon Badlands
    6 Aug 2021 Ochoco Mining District Field Trip by Carrie Gordon & Derek Loeb
    28 Jul 2021 Deschutes River Geohydrology Field Trip
    27 Jun 2021 COGS Field Trip: Fault Scarps of Mt. Hood (south side)
    27 Mar 2020 Monthly Tours of the OSU-Cascades Pumice Mine
    4 Oct 2019 Deschutes River Field Trip
    14 Sep 2019 Mount Hood Field Trip
    22 Jul 2019 Newberry Volcano Field Trip
    13 Jul 2019 Wildcat Mountain Caldera Field Trip
    28 Jun 2019 Fire and Water: Recent mafic volcanism of the central Oregon Cascades
    16 May 2019 Geology of the Scout Camp loop trail along the middle Deschutes River
    27 Apr 2019 Geology of Shevlin Park
    3 Nov 2018 Hydrovolcanoes of Central Oregon Field Trip
    23 Oct 2018 Crooked River Caldera Field Trip
    23 Sep 2018 Mount Bachelor Volcanic Chain Field Trip
    14 Sep 2018 Clarno Fossil Beds Field Trip
    5 Aug 2018 Glacial Geomorphology of the Santiam Pass Area Field Trip
    14 Jul 2018 Lava Butte and Lava Lands Visitor Center
    10 May 2018 Deschutes Formation, Whychus Creek Geologic Field Trip
    1 Apr 2018 Geology of Riley Ranch Nature Reserve Field Trip

    Central Oregon Geoscience Society

    Email: COGeoSoc@gmail.com
    P.O. Box 2154,  Bend, Oregon 97709

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