- What does it mean to be curious?

For my students, curiosity creates opportunities for a bigger and brighter future.

- The beautiful Skagit Flats in Western Washington, these are tulips growing in this landscape, but beneath the tulips is a layer of volcanic material that connects us to a volcano high in the Cascade Mountains, which volcano is it?

We're 5,000 feet above the tulip fields now, and that is an absolutely stunning view of Glacier peak volcano.

Would you agree?

Most people don't get a chance to see this beauty, and we've got it right here.

Do you know the names of the five active strata volcanoes in the state of Washington?

I'll bet you do.

Mount Rainier, Mount St. Helens, Mount Adams.

Mount Baker and Glacier Peak.

But many people don't know about Glacier Peak because it's tucked high in the Cascades and not easily seen from down low in civilization.

This mountain is 9,000 vertical feet above the Sato River Valley.

There's active lava domes.

There's rivers of glacial ice on that mountain.

It's erupt many times in the past, and we are concerned about a future eruption of this mountain.

What does it look like when Glacier peak volcano erupts and what might be flowing down the river valleys away from the erupting volcano.

So how do we know the volcano's been active recently, like a layer of volcanic ash down here among the trees?

Yeah, but this trail and this whole valley bottom is absolutely chock full of these gorgeous blocks of pumice.

You heard of pumice?

This is the stuff that floats in water.

There's so much pore space inside of this very fragile, delicate volcanic deposit.

Pumice forms up towards the top of the volcano at a vent where gases are being injected into the magma, and you get this very porous material.

So the pumice in this case traveled tens of miles down the river, valleys carried by water.

They're rounded blocks of pumice, but on the other side of glacier peak volcano up to 20 miles away.

Over by Lake Shalan, there's blocks of pumice that are angular that clearly got sent through the air.

That's an incredibly explosive eruption 13,000 years ago.

There's more though than pumice.

On this side of the mountain.

A recent landslide has exposed an incredible cliff showing many layers hinting at different kinds of activity coming down these river valleys away from glacier peak volcano.

So when the volcano erupted, it was not lava that flowed all the way to the tulip fields.

Instead, it was something that we call lahar material or volcanic mud flow.

Have you heard of such things?

You can see in this beautiful exposure that there have been multiple eruptions and multiple mud flows with the history of glacier peak volcano.

It's not that the mountain was erupting mud.

Instead, a flank of the volcano became unstable and started to slide.

It was truly a landslide.

And as that slide continued to flow down into the valley, the rock and ash and water and glacial ice all mixed together into a slurry, the consistency of liquid, concrete.

That's what we should visualize for these deposits when they were active.

And if we're filling the valley from valley wall to valley wall more than 50 feet thick, that means that everything is devastated in the path of one of these lahars.

Wow.

So that beautiful mountain, so graceful glacier peak volcano, and so remote has a very real connection.

And dare I say it, a very real threat.

A volcanic threat.

A volcanic hazard to many residents in Western Washington.

Why?

I think we know why we've been talking about it.

This cone is active and when it next erupts, the potential for a major volcanic mud flow coming down a river valley like this, the Sato River Valley is very real.

Why?

We have 50 feet of lahar down in the trees.

We saw it in this episode, and that lahar deposit extends 80 miles from Glacier peak volcano down to Puget Sound, the tulips.

So if that has happened so often in the past 13,000 years ago, 5,000 years ago, it seems likely it will happen in the future.

And we need to take note of these geologic facts, a geologic thread between Puget lowland and beautiful remote glacier peak volcano.

- This series was made possible in part with the generous support of Pacific Science Center.