Leslie Gulch-Mahogany Mountain Caldera

Join Geologist Mark Ferns for an incredible geologic journey through Succor Creek to Leslie Gulch. During this field trip we will be looking at the Mahogany Mountain Caldera, a large rhyolite complex whose core is well exposed in Leslie Gulch. This is largely a ‘look at the scenery’ trip that is not designed for pounding on rocks. The Mahogany Mountain Caldera is an important link between the Yellowstone Hot Spot and the Columbia River Basalt. It is only in the last ten years or so that the geologic model tying the Yellowstone Hot Spot Trend and the Columbia River Basalt Province together has begun gaining acceptance. The trip will include about 8 stops with the first being at Succor Creek for a lunch/bathroom break.

Meetup

1) Meetup at 8:45 AM at Meridian Albertson: 3301 W Cherry Ln, Meridian, ID 83642.

(exit Ten Mile Rd NORTH off Hwy 84miles to Cherry. Albertsons is on SW corner of Cherry Ln & Ten Mile.) Park near the McDonalds, but not in the McDonalds parking lot. Look for Barb's white Ford Explorer SUV.

2) We can only take 6 cars, so if you have a 4 seater pick-up or SUV we ask you to bring that and we will pick 4 for ride sharing in addition to Barb's SUV and Mark's car. The roads are dirt with limited parking so we need to plan accordingly.

3) Each passenger must have a seatbelt, and vehicles should have a full tank of gas. The trip is approximately two hours each way, not including stops. Museum volunteer Barb Beatty will assist in organizing carpools.

4) We will leave Meridian Albertsons at 9 AM in six cars for the 50 minute drive to the Homedale Albertsons, where we will pick-up our guide, Mark Ferns, at 10:00am. Mark will be our guide on the tour!"

Alert: If you are going straight to the Homedale Albertsons. PLEASE let Barb know, 602-228-5097. We don't want to leave any one behind and we need to arrange car pooling.

Attendance Limitations

Limited to 6 cars or about 20 people. Everyone must pre-register. Because of the limited number of cars, we can’t handle ‘No-shows’ so please cancel online or contact Barb if you find you can't go after you register.

Preparation and Gear

Bring lunch, snacks and water. Be prepared and dressed for the weather.

Fees and Refund Policy

Sponsored by Idaho Museum of Mining and Geology (IMMG), 2455 Old Penitentiary Rd. Non-members of the Museum pay $20 plus an Eventbrite fee; IMMG members and children attend for free.

Full refunds will be issued if IMMG cancels the trip due to weather. Please provide a valid email address when registering and check it the day before the event for possible cancellation updates.

Contact Information

For questions, contact [email protected].

About the Guide

Mark Ferns was born and raised east of the historic mining camp of Jacksonville in Southern Oregon. His fascination with geology began early in life. After returning from the US Army in 1972, he earned geology degrees from the University of Oregon. In 1979, Ferns started his career as a geologist with the Oregon Department of Geology and Mineral Industries (DOGAMI), working in Baker City. His initial projects involved cataloging old reports and mapping gold veins in northeast Oregon. In the late 1980s, he led a geologic mapping project during a gold rush in the Owyhee country, contributing to new discoveries and expanding geological understanding.

After retiring in 2011, Ferns taught geology and mining history at Eastern Oregon University, developing engaging stories for students. He continues to live in Baker City, exploring geology and contributing to museum exhibits, with over 40 years of published geological maps and publications.

Further Reading

This is very technical material but check out pages 33-38 for info that relates to this field trip.

Field-trip guide to Columbia River flood basalts, associated rhyolites, and diverse post-plume volcanism in eastern Oregon

Scientific Investigations Report 2017-5022-https://pubs.usgs.gov/publication/sir20175022O

Waiver and Agreement

This adventure requires a waiver . By signing up for this field trip, the registered individual assumes all risks for themselves and those on their ticket, including possible dangers and hazards associated with the trip offered by the Idaho Museum of Mining and Geology (IMMG). The participant agrees to hold harmless the trip leaders, IMMG, and all officers and representatives from any claims, losses, or damages (including attorney’s fees and costs) arising from injury, death, property damage, inconvenience, or financial loss due to delay or other causes by reason of participation. The participant also acknowledges responsibility for carrying their own automobile, life, and health insurance and understands that use of alcohol or drugs may impair judgment and coordination, holding IMMG harmless from any claims resulting from such use.

For questions, please contact [email protected].

Know what’s Happening Next — before everyone else does.

Get App

Host or Publisher Idaho Museum of Mining and Geology