​​​​Snow Productions BI 

Bainbridge Island Geology: Video Previews, Field Trips

Discover how a small island in Puget Sound can reveal the larger picture.


Next Screening:
September 26, 2018
Bainbridge Cinemas on Madison Avenue
Bainbridge Island, WA
6:00 and 7:00 PM
Duration of the film is close to 2 hours. The two screenings overlap in time.

To receive a link for seat reservations,
please send a request through the contact page on this website.



Part One, The Blakeley Formation and The Blakely Harbor Formation (30 minutes)

We explore the foundations, the oldest rocks and the oldest part of the geological history of our island.  The Blakeley Formation underlies the south end of our island from Restoration Point to Fort Ward Park.  Marine fossils tell us that this sandstone formed beneath the sea 25-30 million years ago.  Nearby, outcropping at Rockaway Beach, the Blakely Harbor Formation contains chunks of trees and basalt pebbles deposited by rivers 13 million years ago.

Both of these formations, thousands of feet deep, have been tilted up 60 degrees and more by movement on the Seattle Fault.

Part Two. Faults and Earthquakes (45 minutes)

We look at how rocks are folded and faulted – and the three sources of earthquakes in our area: the subduction zone beneath the Pacific Coast, the breakup of the subducting plate 30 miles under the Puget Sound Region, and compression of the Earth’s crust, which creates the Seattle Fault and multidirectional faulting throughout the region

Part Three, Our Glacial Heritage (about 45 minutes)

Most of the island has been built up and blanketed by glacial deposits.  We explore the processes that formed both hard-pan near the surface and permeable aquifer layers deeper down, as well as our hilly landslide-prone topography

Seattle Fault Zone on Bainbridge Island