Geology of the Mayacamas

Online Lecture: Thursday, September 23, 2021, 7pm-8:30pm
Field Exploration: Saturday September 25, 2021 9am – 12:30pm

$35 per person ($30 for Friends of Pepperwood)
Ages 13 and up welcome
Meet at the Dwight Center (field class), and online via Zoom (lecture)

Have you ever wondered about the diversity of rocks and landforms that can be seen in our local landscape – how did they get here, what are they made of? What is the Franciscan Mélange? How are faults and volcanoes represented here? From the unique topography of the Coast Ranges to the soils and plants that thrive here, the features we see all around us are controlled by geology. Learn to see this landscape from a geological perspective with this 2-part class. Through an engaging online lecture plus field exploration taught by Rebecca Perlroth, you will learn basic concepts of geology, earth history, and the rock cycle through a local lens. Discover how Pepperwood is representative of our region’s fascinating geology, and walk away with a better understanding of the forces which have shaped our landscape over millennia.

The field portion of this event will include a moderate hike of up to 3 miles.

Rebecca Perlroth has spent the past 20 years studying and teaching the geology of California, and currently teaches geology at Santa Rosa Junior College. She earned her BS from Tulane University, and her MS from UCLA.

Please note: All events will follow current regional health safety guidelines. Please bring a mask – we will require masks to be worn indoors during this event (this includes in the bathrooms), regardless of vaccination status. Masks are not required while outdoors. Please practice good hand washing hygiene, and physical distancing when possible. If you do not feel well, please do not attend.

Back To All Events


Register for this event using the secure form below. 

To register, select the applicable level below, either General or Friends of Pepperwood and click +Add. On mobile devices, please scroll all the way to the right to find the +Add button. In the pop up window, enter your information and scroll to the bottom to click “Continue”. Next, on the main form, you may add your additional donation amount in the open field, then click the green “Continue” button to move to the final page for payment. Click the green “Process” button on this final page to complete your transaction. 

For all questions about this event, please contact Holland Gistelli, Education Program Coordinator, at or (707) 591-9310 x 124.

Friends of Pepperwood: Enter the code you received as a current Friend of Pepperwood to receive your discount. If you’re not sure about your Friends of Pepperwood status or don’t know the code, contact Sloane Shinn, Community Associate, at or (707) 591-9310 x 133. Click here to become a Friend of Pepperwood today!

Registration for Friends of Pepperwood opens Monday, July 19, 2021. Registration opens for the public on Friday, July 23, 2021.