Sonoma State University
October 3, 2026

The Geology of Laguna de Santa Rosa (Part 2 of the Triple Watershed Series)

Sonoma Mountain Triple Watershed

Fairfield Osborn Preserve
Sat, Oct 3, 10:00 am – 1:00 pm

Register Here

Admission Fees: none

The Triple Watershed Series 

Join geologist Nicole Myers, CEI's Program and Outreach Specialist, to explore the geologic history of the three watersheds of Sonoma Mountain. Learn how the formation of the San Andreas Fault System lifted the rocks of Sonoma Mountain out of the depths of the ocean, then caused millions of years of volcanic eruptions. Explore the oceanic and volcanic rocks of the mountain that record 180 million years of Earth history, the faults that have formed beautiful landscapes over the last 20 million years, and the streams that have been carved into the mountain as water flows to the Pacific Ocean by way of the Russian River and San Pablo Bay. 

This event is part of a series! Check out the Petaluma River Watershed event at Lafferty Ranch on September 19th at 9-11:30am, a collaboration with Sonoma Mountain Preservation & Landpaths. The Sonoma Creek Watershed Rocktober event at Jack London State Historic Park is on October 17th at 11am-3pm in a collaboration with Jack London Park Partners

 

Presenter 

Nicole Myers, M.S. in Geological Sciences, developed a passion for understanding the Earth from a childhood fascination with rocks and volcanoes, and now teaches others to appreciate planet Earth. Nicole has been teaching earth science classes, including geology, climatology, & Earth history for more than 20 years. She currently teaches Geology and Earth Sciences at Sonoma State University (SSU) through the Applied Human and Environmental Sciences DEpartment and Osher LIfelong Learning Institute (OLLI) and through Appreciating Earth, and is the SSU Center for Environmental Inquiry (CEI) Program & Outreach Specialist. Nicole brings her enthusiasm to the community by offering Earth science field explorations and presentations. 

 

Logistics 

The maximum hike will be ~3 miles with a 480-foot elevation gain. We will be walking on trails over uneven, occasionally steep, ground. Walking sticks might be helpful.

  • Fairfield Osborn Preserve is a 15-minute drive from Sonoma State University's main campus, on Lichau Road in Penngrove. Driving directions are available here in English and in Spanish.
  • Parking is limited so please consider carpooling, and park close together. Let us know if you plan to carpool so we can open more registration spots accordingly.
  • The preserve gate will be unlocked 15-minutes prior to the start time of the event. The preserve gate will be locked 15-minutes after the start of the event time. It is not possible to join the event late or to leave the event early.
  • We will meet outside at the Federated Indians of Graton Rancheria Learning Center, which is across the footbridge on the east side of the parking lot.
  • A restroom, sink for hand-washing, and potable water are available on site.
  • Participants must sign a waiver upon arrival.
  • This event is appropriate for minors 12 years and older. All minors must be accompanied by a legal guardian for the entire event (the parent's/guardian's email can be used for their registration).
  • Pets and smoking are not permitted.
  • Due to narrow, rocky, unpaved trails, sturdy shoes for hiking are required and no strollers are permitted.
  • This is a rain or shine event, though severe storms may cancel.
  • No previous experience or knowledge is required to participate.

What to Bring

Sturdy footwear for hiking is required. Please bring a backpack, a water bottle, and snacks for the trail. Layered clothing, long pants, toe-covered shoes, rain gear, a hat, sun protection, and insect protection are recommended. Walking sticks may be helpful. 

How to Sign Up

See registration link above. Each person should register separately. 

This event is free of charge.

About the Center

Sonoma State University’s Center for Environmental Inquiry empowers university students to work with community members on the environmental challenges of the North Bay. Our mission is to create an engaged and environmentally ready society, one where all people have the skills to find solutions to the challenges facing our earth. SSU Preserves are open to everyone engaged in education or research. Reservations are required.

Contact Email: myersni@sonoma.edu
Contact Phone: 707-664-3869

Sonoma State University acknowledges the Coast Miwok, Central and Southern Pomo, and the Wappo as the traditional stewards of our preserved lands. Let it be acknowledged that the Sonoma State University campus is located within the traditional homelands of the Federated Indians of Graton Rancheria. Sonoma State offers deep gratitude to the original stewards of this land and recognizes its immense historical, spiritual, and personal significance to the Native nations and peoples of this region.

Sonoma State University reconoce a los Miwok de la costa (Coast Miwok), los Pomo del centro y del sur (Central and Southern Pomo), y los Wappo como los guardianes tradicionales de nuestros terrenos preservados. Cabe destacar que el campus de Sonoma State University está ubicado dentro de las tierras tradicionales de los Indios Federados de Graton Rancheria (Federated Indians of Graton Rancheria). Sonoma State expresa su profunda gratitud a los guardianes originales de esta tierra y reconoce el inmenso significado histórico, espiritual, y personal a las naciones y pueblos indígenas de esta región.