Nick Zentner Unveils The Mysteries Of Wenatchee’s Saddle Rock

Saddle Rock - an iconic pair of giant rock pinnacles looming above Wenatchee. 

Seattle’s Public Broadcasting Station - KCTS 9 has an educational geology show called, Nick on the Rocks. The host, Nick Zentner, is a professor of Geology at Central Washington University in Ellensburg.

I’m glad KCTS spotlights Nick's vast knowledge on Pacific Northwest geology.

He does a great job of explaining the complex topics - to the masses, in a very easy-to-understand presentation.

He’s extremely good at what he does. 

How did Saddle Rock appear above Wenatchee?

Saddle Rock and the other pinnacles in greater Wenatchee are a result of volcanic activity.

It is recently believed to have formed 44 million years ago - older than the famous Cascade volcanoes.

Interesting to know that Mt. St. Helens, Mt. Rainier, and Mt. Baker are all younger than the formations at Saddle Rock. 

What kind of rock makes up Saddle Rock?

Nick explained that the material that makes up the iconic pinnacles - are not typical of volcanic rock. The rocks of Saddle Rock are rhyolite - pink volcanic rocks with little white chunks, made up of little smoky quartz and crystals. 

Rhyolite is very stiff, sticky lava, and so each of these pinnacles is a rhyolite dome. Nick Zentner’s origin story for the rhyolite is very descriptive.

‘A squirt of very toothpaste-like magma. It was part of a very explosive volcanic system.’ - Nick Zentner, CWU Geology professor.

Was there a Super Volcano underneath Wenatchee?

The 44 million-year-old rhyolite that make up Saddle Rock, have the same story of the many outcrops above ground and visible in the area, Wenatchee Dome, Castle Rock, Black Thumb, and Rooster Comb have the same rhyolite rock.

The older than the Cascades burst above the surface as a result of a violent pyroclastic ash flow.  Nick explains that the outcrops of rhyolite probably came from some sort of supervolcano rather than then a composite cone volcano. The pinnacles of rhyolite lava were once underground fingers of magma that worked their way up through soft sandstones. Some of them got to the surface and exploded violently.

Geologists like Nick are still trying to work out the details.

Watch Nick tell this story here and check the many episodes of Nick on the Rocks that spin yarn on the varied and interesting geology in the great Pacific Northwest.

KCTS 9 Cascade PBS via YouTube

INFO: KCTS 9