Beauty and the Beast: Plate Tectonics and Geological Hazards...

Cascadia EarthScopeEarthquake and Tsunami

Education Program (CEETEP)

Beauty and the Beast:Plate Tectonics and

Geological Hazards ofthe Pacific Northwest

Otter Crest State Scenic Viewpoint,Oregon

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Beverly Beach State Park, Oregon

Goal and ObjectivesCEETEP Training Workshop

Objectives. Participants will be able to:1. Explain how the landscape of western Oregon formed.2. Discuss geological hazards of the Oregon Coast.

Goal: To provide coastal educators with background knowledge,strategies, and materials to engage students and visitors on thescience of, and preparedness for, earthquakes and tsunamis.

3. Incorporate the region’sgeological landscape andgeophysical monitoringinto lesson plans andinterpretive programs thattell the story of the Coast’sformation and potential forearthquakes and tsunamis.

Earth Science Literacy Principles

1. Earth scientists use repeatable observations andtestable ideas to understand and explain our planet.

2. Earth is 4.6 billion years old.

3. Earth is a complex system of interacting rock,water, air, and life.

4. Earth is continuously changing.

5. Earth is the water planet.

6. Life evolves on a dynamic Earth andcontinuously modifies Earth.

7. Humans depend on Earth for resources.

8. Natural hazards pose risks to humans.

9. Humans significantly alter the Earth.

Big Ideas:

http://www.earthscienceliteracy.org

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U. S

. Geo

logi

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Mt. St. Helens National VolcanicMonument, Washington

Crater Lake National Park, Oregon

“The same geological processes that threaten our lives with earthquakesand volcanic eruptions also nourish our spirits by creating the spectacularmountains, valleys, and coastlines of the Pacific Northwest.”

Beauty and the Beast

CascadeVolcanoes

1. Why are there twoparallel mountainranges in the PacificNorthwest?

National ParkLands in the

Pacific Northwest

CoastalRanges

Most of thePeople

2. Why are thereearthquakes,tsunamis andvolcanic eruptions?

E. L. Orr and W. N. Orr, “Geology of Oregon,”Kendall/Hunt Pub. Co., 5th Edition, 1992.

Geologic Provinces of Oregon

Making Connections:

Ecoregions of Oregon

Oregon’s ecology is closely tied to Oregon’s geology.

Parks and Plates©2005 Robert J. Lillie

What forms the spectacularlandscapes of the Pacific Northwest?

NATIONAL PARKLANDS

Why are there earthquakes,tsunamis, and volcanic eruptions?

TheBeast

Beauty

Cracked Egg Shell!Parks and Plates

©2005 Robert J. Lillie

©19

77, M

arie

Tho

rpe

Beauty

Plate Tectonics: Mountain Ranges• Most mountain ranges occur along the boundaries of movingplates.

Plate Tectonics: Earthquakes and Volcanoes

Modified from USGS Graphicsand Lillie, 2005, “Parks and Plates”

• Most volcanoes and earthquakes occur along plate boundaries.• The deeper quakes (green and blue) occur where one plate divesbeneath another (subduction zones).• Pacific “Ring of Fire”

TheBeast

PLATE BOUNDARIES• Divergent:

– Plates move awayfrom one another.

– Volcanoes andShallow Earthquakes

• Convergent:– Plates move toward

one another.– Volcanoes and very

large earthquakes• Transform:

– Plates slide past oneanother.

– Earthquakes but novolcanoes

• (Hotspot):– Plate rides over

plume of hot mantle.– Lots of volcanism.

Parks and Plates ©2005 Robert J. Lillie

Cascadia

Subduction

Zone

Coa

st R

ange

Will

amet

teV

alle

y

Cas

cade

Vol

cano

es

Basin and Range Province

ColumbiaPlateau

Convergent Plate Boundary(Subduction Zone)

Divergent Plate Boundary(Continental Rift Zone)

Hotspot (Mantle Plume Head)

Nat

iona

l Aer

onau

tics a

nd S

pace

Adm

inist

ratio

n

The Whole Earth andPlate Tectonics

We need to understandwhat goes on inside the

Earth.

Depths inMiles

Oreo®

Cookie Depths inKilometers

Oreo® Cookie

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Oreo® Psycho-Personality Test www.superkids.com/aweb/pages/humor/050199.sht

• Psychologists have discovered that the manner in which peopleeat Oreo® cookies provides great insight into their personalities.Choose which method best describes your favorite method ofeating Oreos:

• 1. The whole thing at once.2. One bite at a time.3. Slow and methodical nibbles examining the results of each bite

afterwards.4. In little feverous nibbles.5. Dunked in some liquid (milk, coffee …..)6. Twisted apart, the inside, then the cookie.7. Twisted apart, the inside, and toss the cookie.8. Just the cookie, not the inside.9. I just like to lick them, not eat them.10. I don’t have a favorite way because I don’t like Oreos.

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6. Twisted apart, theinside, then the cookie.

• You have a highly curious nature.• You take pleasure in breaking things apart

to find out how they work, though you’renot always able to put them back together,so you destroy all the evidence of youractivities.

• You deny your involvement when things gowrong.

• You are a compulsive liar and exhibitdeviant, if not criminal, behavior.

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Sliding Plate over Asthenosphere

Transform Plate Boundary

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PacificPlate

NorthAmerican

Plate

SanAndreasFault

San Andreas Fault Parks and Plates©2005 Robert J. Lillie

Transform Plate Boundary

Mar

shak

, EAR

TH (

Nor

ton,

200

5)


The Pacific Plateslides past the North

American Platealong the San

Andreas Fault inCalifornia.

TransformPlate

Boundary


TransformPlate

Boundaries

Earthquakes in the Pacific Northwest

• Where are the bigearthquakes along theCascadia SubductionZone?

• What about earthquakesbetween the Pacific andJuan de Fuca Plates?

• And earthquakes on theoverriding NorthAmerican Plate?

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Divergent Plate Boundary

NorthAmerica Africa

AtlanticOcean

Nat

iona

l Geo

grap

hic M

id-A

tlant

ic Ri

dge

(Dive

rgen

t Pla

te Bo

unda

ry)

NorthAmerica

Africa

Iceland

Iceland

TheBasin and Range

Provinceis a Continental Rift

Zone, the early stagesof plate divergence

Divergent PlateBoundary

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Plates Pulling Apart--Continental Rift Zone

WesternNorth

America

Basin andRange

Province EasternNorth

America

ActiveContinentalRift Zone

NationalPark

Lands

Death ValleyNational Park

282 Feet Below Sea Level

Death Valley

Panamint Mountains

Death Valley National Park, California


Steens Mountain(Range)

Alvord Dessert(Basin)

Abert Rim(Range)

Lake Abert(Basin)

Winter Ridge(Range)

Summer Lake(Basin)

(Range)

Klamath Lakes(Basin)

www.iris.edu (Animation by Jenda Johnson - Time 0:31)

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Klamath Basin, Oregon


View looking south fromCrater Lake National Park

Fault Escarpment

(Rift Valley)Klamath Basin

1993 – Person killed when rock fellon car on Hwy 97 at Modoc Point

Mountain Range

Klamath Falls Earthquake,Sept. 20, 1993

Continental Rifting in theBasin and Range Province

Two earthquakes (one a magnitude 5.9and one a 6.0) struck KlamathFalls the night of September 20, 1993,damaging more than 1000structures and claiming two lives.


Earthquakes in a Continental Rift Zone

TheBeast

Fault Escarpment

Earthquakes in the Pacific Northwest

• Where are the bigearthquakes along theCascadia SubductionZone?

• What about earthquakesbetween the Pacific andJuan de Fuca Plates?

• And earthquakes on theoverriding NorthAmerican Plate?

Africa

SouthAmerica

Core

LowerMantle

AtlanticOcean

AsthenosphereLithosphere

Trench

Mid-AtlanticRidge

Mod

ified

from

Ham

blin

and

Chris

tians

en, 2

001 Divergent Plate Boundary: Plates Manufactured

Convergent Plate Boundary: Plates Recycled

Giant Re-Cycling Machine!!

Osorno volcano near Puerto Montt, Chilehttp://whatonearth.olehnielsen.dk/volcanoes.asp

Andes Mountains, South America


CascadiaSubduction

Zone

Subduction Zones rim the Pacific Ocean

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Plate Tectonics--Subduction Zone


Juan deFuca Plate North

AmericanPlate

CascadiaSubduction

Zone

Oregon

Cascadia

Subduction

Zone

Coa

st R

ange

Will

amet

teV

alle

y

Cas

cade

Vol

cano

es

CascadeVolcanoes



Pacific Northwest

CoastalRanges


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Olympic National Park,Washington

Coastal Ranges

Layers Lifted out ofthe Sea

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Mt. Rainier National Park,Washington

Cascade Mountains

Steep, ExplosiveVolcanoes

Beauty

TheBeast


Subduction of the Juan deFuca Plate forms theCoastal Ranges andCascade Volcanoes

CoastalRanges

CascadeVolcanoes

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Subducting Juan de Fuca Plate forms two parallelmountain ranges in the Pacific Northwest.

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Oceanic sediment and basalt scraped off subducting plate,forming Coastal Mountains.

Sediment andBasalt Scraped offSubducting Plate

Olympic and otherCoastal Mountain

Ranges

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Subducting plate dehydrates, forming Cascade Volcanoes.

Plate SweatsHot Water

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Subducting plate dehydrates, forming Cascade Volcanoes.

VolcanicMountain

Range


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Puget Sound and the Willamette Valley are low-lying regionsbetween the rising mountains.

Puget Sound/Willamette Valley

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NationalParks

represent thetwo different

mountainranges.

View across Willamette Valley to Three Sisters

Marys Peak Recreation Area, Oregon

Coast Range

Willamette Valley

Cascades

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Coast Range

Willamette Valley

Cascades

Mt. St.HelensNVM

CascadeVolcanoes

National Park Lands inActive Volcanic Arc

Parks in the Cascadesshowcase volcanoesformed above thesubducting plate.

Why are the Cascade Volcanoesin such a straight line?

Subduction leads to Volcanism

http://emvc.geol.ucsb.edu (Animation by Tanya Atwater - Time 0:13)

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The Cascade Volcanoes form above the line where the topof the plate reaches ~ 50 miles (80 km) depth.

VolcanicMountain

Range


How deep is the top ofthe subducting plate

beneath coastal parks?


The Coast Rangecontains Basalt andSedimentary Layers

originally deposited onthe Floor of the Ocean

Ranger Jen’s OreoSubduction Demo

Coast ranges arematerial scraped off

the ocean floor.

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Olympic National Park,Washington

Coastal Ranges

Layers Lifted out ofthe Sea

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Tyee FormationMarine Sandstones and Shales

~ 45 Million Years Old (Middle Eocene)

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Devils Punch Bowl State Natural Area, Oregon

Astoria FormationMarine Sandstones and Shales

~ 18 Million Years Old (Early to Middle Miocene)


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Astoria FormationMarine Sandstones and Shales

~ 18 Million Years Old (Early to Middle Miocene)

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Beverly Beach State Park, Oregon

Yaquina FormationMarine Sandstones and Shales

~ 22 Million Years Old (Early Miocene)

Beauty

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Beverly Beach State Park,Oregon

Yaquina FormationMarine Sandstones and Shales

~ 22 Million Years Old(Early Miocene)

Marys PeakCorvallis,Oregon

Oregon StateUniversity

DowntownBeanery

CampusBeanery

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Marys Peak

Basalt Lava Flows- Manufactured in Ocean Realm

- About 55 million years ago

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Formation of Pillow Lava

The formation of pillow lava in the deep ocean has never been observed, but it probably looks a lot like this. This movie shows pillow lavaflowing underwater off the coast of Hawaii, after it was erupted on land and flowed into the ocean. Video footage from the movie "PeleMeets the Sea" courtesy of Richard Pyle ([email protected]) at Lava Video Productions.http://oceanexplorer.noaa.gov/explorations/04fire/background/volcanism/media/pillow_lava_video.html

Mar

shak

, EAR

TH (

Nor

ton,

200

5)

Oceanic Crust

Lava Erupts into Cold Ocean Water

Formation of Pillow Lava

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Siletz River VolcanicsOceanic Basalt Lava Flows

~ 55 Million Years Old (Early Eocene)

CascadeVolcanoes



Pacific Northwest

CoastalRanges


We can see what’son the surface.

Active Tectonics of the Pacific Northwest

How does the surfacechange as a responseto subduction?

How do we know what’sbeneath the surface?

- Where are the earthquakes?- Why are they there?- How often does each type occur?

- How big is each type?- How destructive is each type?

Oregon Earthquakes“The Big One” occurs when

plates lock for centuries,then suddenly let go!

Big Ones happen every 200to 600 years. The last onewas in the year 1700 …….

Four Types of Earthquakes inCascadia Subduction Zone

1) Slab Earthquakes:– Within Juan de Fuca Plate– Up to 40 miles (60 km) depth– Up to Magnitude 7

2) Locked Zone (Mega-Thrust)Earthquakes:

– Between Juan de Fuca and NorthAmerican Plates

– 5 - 10 miles (8 - 15 km) depth– Up to Magnitude 9

3) Upper Plate Earthquakes:– Within North American Plate– 1 - 10 miles (2 - 15 km) depth– Up to Magnitude 7

4) Volcanic Earthquakes:– From magma shallowing beneath

Cascade volcanoes– 1 - 5 miles (2 - 10 km) depth– Up to Magnitude 5.5

12

3 4

TheBeast

1. Nisqually, Washington,2001 (M=6.9)

2. Cascadia, 1700 (M=9?)3. Scotts Mills, Oregon,

1993 (M=5.6)

4. Mt. St. Helens, Washington,1980 (M=5.5)

5

6

Rifting: KlamathFalls, 1993, M = 6.0

Offshore:M up to 7

Joe

Gre

en

Cape Perpetua Scenic Area, Oregon

Basalt Lava FlowsManufactured in the Ocean~35 million years ago, then addedto the edge of the continent.

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Heceta Head Lighthouse State Scenic Viewpoint, Oregon

Yachats FormationOceanic Basalt Lava Flows

~ 35 Million Years Old (Late Eocene - Oligocene)

Can we design an effective interpretativetalk on geology for the Oregon Coast?

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Seal Rock State Park, Oregon

What about these younger lava flows?Only 9 – 15 million years old

Can we design an effective interpretativetalk on geology for the Oregon Coast?

Orr

, Orr

, and

Bal

dwin

, “G

eolo

gy o

f Ore

gon,

” 4th

Edi

tion,

199

2

Basalt fromOcean Realm(63-29 Million

Years Ago)

Basalt from ColumbiaPlateau

(15-9 Million Years Ago)Age of

Basalt alongOregon andWashington

Coasts

http://www.geo.utep.edu/kidd/Vol_eq_plates.html

Plate BoundariesEarthquakes (yellow dots)Active Volcanoes (orange triangles) The

Beast


Plate Boundaries

Tectonic activityfar from plateboundaries.

Nat

iona

l Geo

grap

hic

Soci

ety

FormingToday

45 MillionYears Old

21 MillionYears Old

NorthwestwardPlate Motion

Hawai`i – Emperor Hotspot Track

Pacific Plate Riding Over Hawaiian HotspotParks and Plates ©2005 Robert J. Lillie

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PacificPlate

Hawaiian Islands

HOTSPOT

U. S

. Geo

logi

cal S

urve

y ,

Haw

aiia

n Vo

lcan

o O

bser

vato

ry

On Top of HotspotParks and Plates

©2005 Robert J. Lillie

Hawai`i Volcanoes National Park, Hawai`i


Plate Boundaries

YellowstoneHotspot

Columbia Plateau –Yellowstone

Selected Parklands

Oregon StateParks

NationalPark Service

U. S. ForestService

John DayFossil Beds NM

Yellowstone NP

Bureau LandManagement

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John Day Fossil Beds National Monument, Oregon

Friendly park rangers engage visitors on thegeology, paleontology, and cultural history of the

John Day Country.

SheepRock

Fossil-BearingLayers

ColumbiaPlateau Basalt

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John Day Fossil Beds National Monument, Oregon

ColumbiaPlateauBasalt

Surfacing of Hotspot

Beauty

Picture Gorge

Yellowstone National Park,Wyoming

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Old Faithful Geyser

On Top of Hotspot

TheBeast

This BBC production brought great globalawareness of Yellowstone as an active volcano

Flood Basalts and Hotspot TracksFlood Basalts and Hotspot Tracks

From Camp and Ross, JGR 2004

Plate Moves

Over Hotsp

ot

Giant Explosive Calderas

YellowstoneSupervolcano

Numbers are age of initial lava eruptionsNumbers are age of initial lava eruptions (millions of years)(millions of years)


(Surfacing ofHotspot)


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NorthAmerican

Plate

Volcanoes

HOTSPOT

Hotspot

ContinentalHotspot

Volcanism

Lava Lamp

ContinentalHotspot

Volcanism

Lava Lamp Columbia Plateau

ContinentalHotspot

Volcanism

Lava Lamp Yellowstone Supervolcano

Flood Basalts and Hotspot TracksFlood Basalts and Hotspot Tracks

From Camp and Ross, JGR 2004

Plate Moves

Over Hotsp

ot

Giant Explosive Calderas

YellowstoneSupervolcano

Numbers are age of initial lava eruptionsNumbers are age of initial lava eruptions (millions of years)(millions of years)


(Surfacing ofHotspot)

Lava flowed all theway to the

Willamette Valleyand Oregon Coast!

Columbia Plateau –Yellowstone

Selected Parklands

Oregon StateParks

NationalPark Service

U. S. ForestService

John DayFossil Beds NM

Yellowstone NP

Silver FallsState Park

YaquinaHeadONA

Bureau LandManagement

MultnomahFalls

U. S

. For

est S

ervi

ce

Beauty

Multnomah Falls,OregonMany of Oregon’s

majestic waterfalls flowover resistant

Columbia PlateauBasalt

Columbia Gorge NationalScenic Area,

Oregon/Washington

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Silver Falls State Park,Oregon

South Falls

Many of Oregon’smajestic waterfalls flow

over resistantColumbia Plateau

Basalt

Yaquina Head Outstanding Natural Area, OregonBu

reau

of L

and

Man

agem

ent

Many of Oregon’s coastal headlands are also resistantColumbia Plateau Basalt

Cape Meares Scenic Viewpoint, Oregon

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Cape Lookout

Columbia Plateau BasaltContinental Hotspot Volcanism

~ 15 Million Years Old (Middle Miocene)

Cape Lookout State Park, Oregon

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Cape Meares

Columbia Plateau BasaltContinental Hotspot Volcanism

~ 15 Million Years Old (Middle Miocene)


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OtterCrest

CapeFoulweather

Cottonwood Canyon State Park, Oregon

Ore

gon

Park

s and

Rec

reat

ion

Dep

artm

ent

Columbia Plateau Basalt

Seal Rock

CapeLookout

Cape Meares

CapeFoulweather


Hat Rock

Rooster Rock

AinsworthCrown Point

Silver FallsSome Oregon State Parks

showcasing ColumbiaPlateau Basalt

CottonwoodCanyonMayer

Cascadia

Subduction

Zone

Coa

st R

ange

Will

amet

teV

alle

y

Cas

cade

Vol

cano

es


ColumbiaPlateau

KlamathMountains

WallowaMountains

BlueMountains

OchocoMountains

StrawberryMountains




Older Mountain Ranges(Subduction and Accretion)

Parksand

Plates –Oregon

Ore

gon

Park

s and

Rec

reat

ion

Dep

artm

ent

Iwetemlaykin State Heritage Site, Oregon

Wallowa Mountains

Mar

shak

, EAR

TH(N

orto

n, 2

005)


AGE OF NORTHAMERICANBASEMENT

ROCKS(Billions Years)

Rocks are oldestnear the center of

the continent(continental shield)

and tend to getyounger outward.

What’s thePattern?

Marshak, EARTH (Norton, 2005)

Terrane AccretionA TERRANE consists of crust that is too thick and

buoyant to subduct. The continent grows outward asterranes come crashing in.

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North AmericanPlate

First Terrane

SecondTerrane

Third Terrane

ForthTerrane

Ocean Plate

Safeway Terrane Accretion

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Ocean Plate

First TerraneSecondTerrane

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Ocean Plate

Third Terrane

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FourthTerrane

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North American

Plate

First Terrane

Second Terrane

Third Terrane

Forth Terrane

OceanPlate

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The Cascadia Subduction Zone is just the latest episode of thePacific Northwest building outward by Terrane Accretion.


Most of Oregon andWashington has been

added to the edge of thecontinent in the past 150

million years

Material addedsince then by

Subduction andTerrane Accretion

Coastline150 MillionYears Ago

Jurassic

� � � � � � � � � � � � � � � � � ��

195Million Years Ago

Ron BlakeyNorthern Arizona

University

� � � � � � � � � � � � � � � � � ��

Rifting of Pangaea;

Opening of the Atlantic ocean


Jurassic


University

� � � � � � � � � � � � � � � � � ��

Rifting of Pangaea;



Jurassic


University

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Jurassic


University

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Cretaceous


University

� � � � � � � � � � � � � � � � � ��

50Million Years Ago

Eocene


University

� � � � � � � � � � � � � � � � � ��

40Million Years Ago

Eocene


University

� � � � � � � � � � � � � � � � � ��

25Million Years Ago

Oligocene


University

� � � � � � � � � � � � � � � � � ��

15Million Years Ago

Miocene


University

� � � � � � � � � � � � � � � � � ��

8Million Years Ago

Miocene


University

� � � � � � � � � � � � � � � � � ��

3Million Years Ago

Pliocene


University

� � � � � � � � � � � � � � � � � ��

Laurentide glaciation

12,500Years Ago

Holocene


University

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PresentDay

Now


University

Tectonic Development ofWestern North America

85 Million Years Ago tothe Present

http://emvc.geol.ucsb.eduFrom: Tanya AtwaterEducational Multimedia Visualization CenterDepartment of Earth ScienceUniversity of California at Santa Barbara

http://emvc.geol.ucsb.eduFrom: Tanya Atwater

Tectonic Development of the Pacific Northwest40 Million Years Ago to the Present

Educational Multimedia Visualization CenterDepartment of Earth ScienceUniversity of California at Santa Barbara

Cascadia

Subduction

Zone

Coa

st R

ange

Will

amet

teV

alle

y

Cas

cade

Vol

cano

es


ColumbiaPlateau

KlamathMountains

WallowaMountains

BlueMountains

OchocoMountains

StrawberryMountains




Older Mountain Ranges(Subduction and Accretion)

Parksand

Plates –Oregon

PLATE BOUNDARIES• Divergent:

– Plates move awayfrom one another.

– Volcanoes andShallow Earthquakes

• Convergent:– Plates move toward

one another.– Volcanoes and very

large earthquakes• Transform:

– Plates slide past oneanother.

– Earthquakes but novolcanoes

• (Hotspot):– Plate rides over

plume of hot mantle.– Lots of volcanism.


Beauty and the Beast: Plate Tectonics and Geological Hazards...

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Transcript of Beauty and the Beast: Plate Tectonics and Geological Hazards...