Central Oregon Geoscience Society upcoming events

Tour de Tuyas Geo-Exploration, Session 1 (4 Oct 2026)

Sun, 04 Oct 2026 16:00:00 GMT

Tour de Tuyas Geo-Exploration, Session 1

Led by Derek Loeb

Sunday, Oct. 4, 9:00 AM - 12:30 PM

Tuyas are flat topped, steep sided volcanic features that are interpreted to have erupted while capped by significant thickness of glacial ice. The Santiam Pass area is one of the best places in the world to easily view these features.

We will meet at the Santiam Pass, PCT Trailhead and after introductions and a geological orientation we will hike just over a mile while gradually gaining about 350 feet of elevation. Along the way we will have great views looking south at our local examples of Tuyas, Hayrick Butte and Hogg Rock. Our destination is an unnamed topographic feature 'No Name Knob' which may be a small Tuya. ('No Name Knob' is my the working name for this feature)

Total mileage will be about 2.5 miles with a gradual elevation gain of plus/minus 350' on a good trail. This area has been burned so there is not much shade or wind breaks. This trip is very much view dependent so low clouds or very bad smoke conditions may lead to a cancellation. Because we will be in a wilderness area, participants is limited to 12. Participants must be a member of COGS or a guest of a member. As always please leave your pets at home as they are not allowed on COGS field trips.

Ride Sharing: I am looking for a volunteer to informally be the ride share coordinator for this trip.

Please contact Derek Loeb ( DerekLoeb@gmail.com ) with any questions.

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.

Tour de Tuyas Geo-Exploration, Session 2 (4 Oct 2026)

Sun, 04 Oct 2026 20:00:00 GMT

Rescheduled

Tour de Tuyas Geo-Exploration, Session 2

Led by Derek Loeb

Sunday, Oct. 4, 1:00 PM - 4:30 PM

Ride Sharing: I am looking for a volunteer to informally be the ride share coordinator for this trip.

Please contact Derek Loeb ( DerekLoeb@gmail.com ) with any questions.

Harney Basin Field Trip (9 Oct 2026)

Sat, 10 Oct 2026 00:00:00 GMT

Harney Basin Field Trip

Led by Dave Sherrod

Friday, Oct. 9, 5:00 PM - Sunday, Oct. 11, 4 pm

Registration Opens Friday, August 28 at 8 AM

Please join Dave Sherrod on a two day exploration of the Harney Basin, south of Burns. We’ll assemble Friday evening (10/9, Day 0) at Malheur Field Station , with field Day 1 on Saturday and Day 2 on Sunday (10/10 & 10/11). Day 1 will explore the basin’s stratigraphy, structure, geomorphology, and lake history from middle Miocene time to present (road stops). Day 2 is devoted to Diamond Craters, a Holocene lava field with a fascinating complex history unlike any other in the western mainland U.S. The Diamond Craters day includes driving stops and a lunch stop at a viewpoint overlooking the craters. Participants have the option of ending the trip here but there is a recommended, but optional, walking tour of the central crater complex, in the heartland of Diamond Craters. This walk is cross country totaling about a mile with modest elevation loss/gain of 200'. The footing is generally good but footwear with good traction is recommended as well as hiking poles if you find them helpful. Please see the flyer prepared by Dave Sherrod for more details:

Harney Basin FT primer_Sherrod_20260727.pdf

The trip is too far from Bend to allow a Bend-based start each day. Malheur Field Station (MFS) , 30 miles south of Burns, will be our accommodations which feature rooms with two twin beds/room at $50/night/person and a full dinner ($25) Friday and Saturday nights. There is also an option for up to three self contained RV sites at $35/night. Participants could also stay or camp offsite. All of these prices will also have 3% added them to cover the credit card processing fee. Priority will be given to filling up the bed space as COGS has a financial commitment to covering that cost. If you would like to share a room with a particular person either register as participant/guest or contact me. If you would prefer to not share a room there is a single occupancy option (essentially you buy both beds and register yourself and a guest named 'Single Occupancy'. Please note that you must provide your own towels, linens or sleeping bag.

Participation in the group dinners is highly encouraged as it is integral to the field trip and introductions and some introductory info will be provided at that time. MFS can provide vegetarian/vegan and gluten free options, and accommodate dietary restrictions but please contact me on this so I can advise MFS. MFS does not provide alcoholic beverages but participants are free to bring and cosume their own. Breakfast, lunches and snacks are the responsibility of the participant. There are kitchen facilities with basic appliances and cooking equipment.

If you would like to use one of the RV camping sites please be aware that the RV must be self contained and no use of the bathroom or shower facilities is permitted. If you want one of these sites or plan to stay offsite please contact me prior to registering. There is a total of 20 bed spaces and total participation will be capped at about 25 participants.

In case of cancellation, refunds will be based on if COGS is able to fill your space or otherwise recover costs.

Contact Derek Loeb ( DerekLoeb@gmail.com ) with questions or to provide me with pertinent info. More information on the Malheur Field Station is provided on this info sheet:

Malheur Field Station Visitor Guide.pdf

Participants must be a member of COGS or a guest of a member. As always please leave your pets at home as they are not allowed on COGS field trips.

Ride Sharing: Details to be determined.

Registration Opens Friday, August 28 at 8 AM