The Fire Within:The Fire Within:

Plate Tectonics & Volcanism Across the Solar SystemPlate Tectonics & Volcanism Across the Solar System

By the Lunar and Planetary InstituteBy the Lunar and Planetary Institute

For Use In Teacher Workshops

USGS Photo by B. Chouet

What’s a Rock?What’s a Rock?

What are the Main Rock Types?What are the Main Rock Types?

How Do They Form?How Do They Form?

How Do You Tell One from How Do You Tell One from Another?Another?

IgneousIgneous

All All igneous rocksigneous rocks cool and crystallize from magma or lavacool and crystallize from magma or lava or consolidate from pyroclastic materialsor consolidate from pyroclastic materials

MagmaMagma is molten material below the is molten material below the surfacesurface

LavaLava is molten material on the surface is molten material on the surface Pyroclastic materialsPyroclastic materials are particles such are particles such

as volcanic ashas volcanic ash

MetamorphicMetamorphic

Changes in minerals, texture, and/or chemical Changes in minerals, texture, and/or chemical composition of a rock that result from changes composition of a rock that result from changes in temperature and pressure … like burial, in temperature and pressure … like burial, contact with hot stuff, extreme crunching …contact with hot stuff, extreme crunching …

No melting!No melting!

Photo by J.P. Lockwood. Figure 24-B, U.S. Geological Survey Bulletin 1595.

Clastic Sedimentary RocksClastic Sedimentary Rocks

Sediment particles (skeletal, rock Sediment particles (skeletal, rock fragment, mineral, plant particles) fragment, mineral, plant particles) derived from erosion (breakdown / derived from erosion (breakdown / transport) of rock that are lithified transport) of rock that are lithified (cemented or compacted)(cemented or compacted)

Carbonate / Carbonate /

Other Sedimentary RocksOther Sedimentary Rocks

Chemical precipitates (halite) or Chemical precipitates (halite) or biologically - produced (organic) biologically - produced (organic) material (shell fragments). material (shell fragments). In-In-situ.situ.

SedimentarySedimentary

Images from http://wrgis.wr.usgs.gov/parks/rxmin/rock2.html

What is the Rock Cycle?What is the Rock Cycle?

From USGS at http://3dparks.wr.usgs.gov/nyc/images/fig6.jpgFrom USGS at http://3dparks.wr.usgs.gov/nyc/images/fig6.jpg

Igneous Part of the Rock Igneous Part of the Rock CycleCycle

From USGS at http://3dparks.wr.usgs.gov/nyc/images/fig6.jpg From USGS at http://3dparks.wr.usgs.gov/nyc/images/fig6.jpg

Igneous RocksIgneous Rocks

All All igneous rocksigneous rocks cool and crystallize from magma or lavacool and crystallize from magma or lava or consolidate from pyroclastic materialsor consolidate from pyroclastic materials

MagmaMagma is molten material below the is molten material below the surfacesurface

LavaLava is molten material on the surface is molten material on the surface Pyroclastic materialsPyroclastic materials are particles such are particles such

as volcanic ashas volcanic ash

Identifying Igneous RocksIdentifying Igneous Rocks

Step 1.Step 1.Is it an igneous rock?Is it an igneous rock?

Interlocking randomly oriented crystals?Interlocking randomly oriented crystals?

Published as figure 14 in U.S. Geological Survey. Bulletin 1595. 1987Published as figure 14 in U.S. Geological Survey. Bulletin 1595. 1987

Identifying Igneous RocksIdentifying Igneous Rocks

ExtrusiveExtrusive or or volcanicvolcanic rocks rocks form at the surface from lava or form at the surface from lava or

pyroclastic materialspyroclastic materials

IntrusiveIntrusive or or plutonicplutonic rocks rocks form from magma in the crustform from magma in the crust

Identifying Igneous RocksIdentifying Igneous Rocks

Igneous rocks have 4 texturesIgneous rocks have 4 textures determined by the cooling rate of magma or determined by the cooling rate of magma or

lavalava TextureTexture

size, shape and arrangement of crystals in a size, shape and arrangement of crystals in a rockrock

4 Cooling-Rate Textures4 Cooling-Rate Textures

Phaneritic – Coarse Grained (Intrusive)Phaneritic – Coarse Grained (Intrusive) visible grains, cooled slowlyvisible grains, cooled slowly

AphaniticAphanitic – Fine Grained (Extrusive) – Fine Grained (Extrusive) with grains too small to see, cooled quicklywith grains too small to see, cooled quickly

Porphyritic –Porphyritic – (Extrusive) (Extrusive) with larger grains surrounded by a finer-with larger grains surrounded by a finer-

grained groundmass grained groundmass cooled slowly first, then more quicklycooled slowly first, then more quickly

GlassyGlassy with no grains with no grains

cooled too quickly for minerals to growcooled too quickly for minerals to grow

Igneous Rock TexturesIgneous Rock Textures

AlsoAlso vesicular texture vesicular texture, with holes , with holes ((vesiclesvesicles) ) indicates the rock formed as water vapor indicates the rock formed as water vapor

and other gases became trapped during and other gases became trapped during cooling of lavacooling of lava

PyroclasticPyroclastic or or fragmental texturefragmental texture containing fragments formed by containing fragments formed by

consolidation of volcanic ash or other consolidation of volcanic ash or other pyroclastic materialpyroclastic material

Identifying Igneous RocksIdentifying Igneous Rocks

Step 2.Step 2.Coarse grained or fine grained?Coarse grained or fine grained?

(Porphyritic or Aphanitic)(Porphyritic or Aphanitic)

From the USGS photo glossary of volcanic terms

Igneous RocksIgneous Rocks

Texture and composition are the criteria Texture and composition are the criteria used to classify most igneous rocksused to classify most igneous rocks

Composition categories are based on Composition categories are based on silica content silica content felsicfelsic (>65% silica) (>65% silica) intermediateintermediate (53-65% silica) (53-65% silica) maficmafic (45-52% silica) (45-52% silica)

Identifying Igneous RocksIdentifying Igneous Rocks

Step 3.Step 3.Light or Dark? … Composition HintsLight or Dark? … Composition Hints

Images from USGS Photo Library

Identifying Igneous RocksIdentifying Igneous Rocks

Step 4.Step 4.What minerals present?What minerals present?Quartz – gray opaque, concoidal fractureQuartz – gray opaque, concoidal fracture

K-Spar - pinkK-Spar - pink

Plagioclase feldspar – white to grayPlagioclase feldspar – white to gray

Muscovite – light, flakeyMuscovite – light, flakey

Biotite – dark, flakeyBiotite – dark, flakey

Pyroxene - LBMPyroxene - LBM

Amphibole - LBMAmphibole - LBM

USGS Mineral Specimen Photography: Bureau of Mines, ___ and Mineral collection of Bringham Young University Department of Geology, Provo, Utah

Igneous Rock ClassificationIgneous Rock Classification

Diagram by staff of LPI

A Classification of Igneous Rocks

Cooling History / Texture

Slow Cooling and Coarse Grained

Fast Cooling and Fine Grained

Very Fast Cooling and Glassy/Cellular

Mafic and Dark Color

Gabbro Basalt

Scoria

Intermediate in composition and color

Diorite Andesite

Felsic and Light Color

Granite Rhyolite Pumice and Obsidian

Green sand beach – why green?Green sand beach – why green?

Image courtesy of Alison Henning, Rice University

Volcanoes!Volcanoes!

Image from http://photo.itc.nps.gov/storage/images/lavo/lavo-Full.00005.html

Lassen Volcanic Lassen Volcanic National Park, CANational Park, CA

Volcanic DepositsVolcanic Deposits

http://volcanoes.usgs.gov/Hazards/What/hazards.html

Shape depends on compositionof magma…

BasalticAndesiticRhyolitic

…and gas content

… and number and size of eruptions

… and the environment of eruption

Volcanic DepositsVolcanic Deposits

http://volcanoes.usgs.gov/Products/Pglossary/basalt.html

Why does silica matter?Why does silica matter? Si - O bonds much stronger Si - O bonds much stronger

than othersthan others

In lava, single silica tetrahedra In lava, single silica tetrahedra flow easily, like little ballsflow easily, like little balls

In lava, large silicate polymers In lava, large silicate polymers flow poorly, like noodlesflow poorly, like noodles

Diagram by staff of LPI

Basaltic LavaBasaltic Lava

High temperature High temperature (1000-1200 C)(1000-1200 C)

LowLowerer silica content silica content

Extremely fluidExtremely fluid

Images courtesy of Alison Henning, Rice University

Basaltic LavaBasaltic Lava Flood basaltsFlood basalts – huge – huge

plateaus (e.g. Columbia plateaus (e.g. Columbia Plateau of Washington Plateau of Washington and Oregon)and Oregon)

Pahoehoe and aaPahoehoe and aa – ropy – ropy vs. jagged blocks (e.g. vs. jagged blocks (e.g. Hawaiian volcanoes)Hawaiian volcanoes)

Pillow lavasPillow lavas – ellipsoidal, – ellipsoidal, cool underwatercool underwater

Images from USGS Photo Glossary of Volcano Terms

Rhyolitic LavaRhyolitic Lava Most felsic, light in colorMost felsic, light in color

Higher silica contentHigher silica content

Lower melting point than Lower melting point than basalt. Erupts at 800-1000 Cbasalt. Erupts at 800-1000 C

Moves 10 X more slowly Moves 10 X more slowly than basaltthan basalt

Tends to be explosive – Tends to be explosive – more gas (water) contentmore gas (water) content

USGS Photo Glossary of Volcano Terms

Gas ContentGas Content Magma rises close to surface, Magma rises close to surface,

pressure dropspressure drops

Volatiles released with Volatiles released with explosive forceexplosive force

Explosive eruptions most likely Explosive eruptions most likely with gas-rich, viscous rhyolitic with gas-rich, viscous rhyolitic and andesitic magmasand andesitic magmas

PyroclastsPyroclasts – rock material – rock material ejected into airejected into air

Image courtesy of Alison Henning, Rice University

Volcanic LandformsVolcanic Landforms Shield volcanoes – Mauna LoaShield volcanoes – Mauna Loa

BigBig Broad, Low SlopeBroad, Low Slope

Properties of lava? Number of flows? Types of rocks?Properties of lava? Number of flows? Types of rocks?

Image from http://hvo.wr.usgs.gov/maunaloa/

Volcanic LandformsVolcanic Landforms

Lava PlateauLava Plateau ExtensiveExtensive Stacked flowsStacked flows Virtually no slopeVirtually no slope

Properties of lava? Number of flows? Type Properties of lava? Number of flows? Type of rock?of rock?

Photo from http://en.wikipedia.org/wiki/Image:3-Devils-grade-Moses-Coulee-Cattle-Feed-Lot-PB110016.JPG

Columbia Plateau

130,000 Km2 x 1.5 km thick

Buried topography

~16 Ma

Cinder ConesCinder Cones Small Small Steep slope (30Steep slope (30oo) ) Basaltic … Basaltic …

hmmmmhmmmm

Properties of lava? Properties of lava? Number of flows? Number of flows? Types of rocks?Types of rocks?

Volcanic Volcanic LandformsLandforms

USGS Photo by K. Segerstrom

NPS image from Capulin, NM USGS image

SmallSmall

Few eventsFew events

Flanks of Flanks of Mauna Kea Mauna Kea

Common on Common on shield volcano shield volcano flanksflanks

USGS Photo Glossary of Volcano Terms

Volcanic LandformsVolcanic Landforms Composite Composite

VolcanoVolcano Big Big High slope High slope

(30(30oo) ) Made of Made of

multiple multiple lavalava and and ashash flows flows

ExplosiveExplosive

Properties of lava? Number of Properties of lava? Number of flows? Types of rocks?flows? Types of rocks?

USGS Photo Glossary of Volcano Terms

Composite Volcano - Mt St HelensComposite Volcano - Mt St Helens

Images from http://vulcan.wr.usgs.gov/Volcanoes/MSH/SlideSet/ljt_slideset.html

PinatuboPinatubo

USGS photo by Dave Harlow

Volcanic Volcanic LandformLandform

DomeDome SmallSmall Steep slope Steep slope

Properties of Properties of lava? Number of lava? Number of flows? Type of flows? Type of rock?rock?

Foreshadowing … Patterns to where types Foreshadowing … Patterns to where types of volcanos occur?of volcanos occur?

If a planet has active volcanos, If a planet has active volcanos, what do we know about the planet?what do we know about the planet?

NASA/JPL/NGA image from http://photojournal.jpl.nasa.gov/catalog/PIA06668

Where Does the Heat Come From?Where Does the Heat Come From?

Hubble Image from http://hubblesite.org/newscenter/archive/releases/1998/38/image/a/

Where Does the Heat Where Does the Heat Come From?Come From?

(Terrestrial Planets)(Terrestrial Planets)

Originally: Impacts (accretion), differentiation, radioactive decay

Presently: Mostly radioactive decay

Image by LPI: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=168

Image by LPI

What Evidence Suggests What Evidence Suggests Volcanism on Other Planets?Volcanism on Other Planets?

NASA image at http://photojournal.jpl.nasa.gov/catalog/pia00254

What Planets Are / Have Been Volcanically Active?

Past• Mercury, Venus,

Earth, Moon, Mars, Io, Titan

Presently

• Earth, Io, Enceledus, Triton

• Probably Venus and Mars

Photo montage from http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=2167

Why Might a Planet Have Ceased Being Volcanically Active?

Image: Lunar and Planetary Laboratory: http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=178

Our MoonWhat do you observe?

Image at http://www.lpi.usra.edu/education/timeline/gallery/slide_61.html

Big Impact Basins Filled by Lava

Apollo image from http://www.lpi.usra.edu/expmoon/Apollo15/A15_Photography_orbital.html

Mare Imbrium

Volcanism after impacts – most before 3 Ga (to 1 Ga)

Fissure Eruption Courtesy of USGS.http://www.geology.sdsu.edu/how_volcanoes_work/Thumblinks/Puuoorift_page.html

Lunar BasaltsLunar Basalts

15555

15016

3.3 Billion Years Old

Apollo image at http://www.lpi.usra.edu/expmoon/Apollo15/A15_BasaltFS.gif

Apollo image from http://curator.jsc.nasa.gov/lunar/compendium.cfm

Lunar VolcanismLunar Volcanism

Aristarchus Plateau

Marius Hills

photo by Lunar Orbiter V at http://history.nasa.gov/SP-168/section2b.htm

Photo of Aristarchus Plateau at

http://lunar.gsfc.nasa.gov/images/gallery/2Craters_br-browse.jpg

MercuryMercury

Tons of Craters Some Flat Plains …

hmmmmmm…

Only ~ 1/3 imaged Messenger

spacecraft on its way to orbit!

Image: http://www.lpi.usra.edu/publications/slidesets/ss_tour/slide_2.html

Craters and PlainsCraters and Plains

500 km

Mariner image at http://photojournal.jpl.nasa.gov/catalog/PIA02948

Venus

Magellan image from http://antwrp.gsfc.nasa.gov/apod/ap020330.html

Venera Images - 1982Venera Images - 1982

Image: http://www.lpi.usra.edu/publications/slidesets/ss_tour/slide_5.html

Sapas Mons – 1.5 km high, 400 km acrossAtla Regio

Magellan image at http://www2.jpl.nasa.gov/magellan/image28.html

Maat Mons – 8 km high, Aphrodite Terra Region

Magellan color image at http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=2085

Courtesy of David P. Anderson (Southern Methodist University) Image at http://www.lpi.usra.edu/publications/slidesets/venus/slide_21.html

Pancake DomesPancake Domes

Single Flows, Steep sides

Height 1/2 - 1 km.

What kind of volcano?

What kind of lava?

NASA Image from LPI: http://www.lpi.usra.edu/publications/slidesets/venus/slide_24.html

Pancake DomesPancake Domes

Rhyolite? Or merely cold,

crystal-rich basalt?

What kind of What kind of volcano?volcano?

What kind of lava? What kind of lava?

USGS photo by R.A. Bailey

What’s missing?

Few impact craters – what does this tell us?

No craters less than 3 km (meteoroid ~ 30 m across)

Atmospheric filter Magellan image from http://antwrp.gsfc.nasa.gov/apod/ap020330.html

MarsMars

dfldjfkdkfjdfldjfkdkfj

MOLA image from http://pds-geosciences.wustl.edu/missions/mgs/mola.html

Olympus Mons

TALLEST Volcano in the Solar System

24 km high550-600 km across

Mauna Loa9 km high (sea floor) 120 km across (base)

Lava flows in last million years?

Viking image at http://photojournal.jpl.nasa.gov/catalog/PIA02982

MarsMars

LPI image at http://www.lpi.usra.edu/publications/slidesets/hawaiivolcanoes/slidespages/slide_01.html

LPI image at http://www.lpi.usra.edu/publications/slidesets/redplanet2/slide_10.html

MarsMars Olympus Mons Image overlain on topography and vertically

exaggerated 10x

MOLA image at http://photojournal.jpl.nasa.gov/catalog/PIA02806

Mars Express images fromhttp://www.esa.int/esaMI/Mars_Express/SEMKC2W4QWD_0.html And

http://www.esa.int/esa-mmg/mmg.pl?b=b&keyword=Olympus%20Mons%203D&single=y&start=5

Broken Cinder Cone?

On Syrtis Major - Shield VolcanoOn Syrtis Major - Shield Volcano

USGS image at http://wrgis.wr.usgs.gov/fact-sheet/fs024-02/

Themis image at

http://themis.la.asu.edu/zoom-20030514a.html

Why Might a Planet Have Ceased Being Volcanically Active?

Hubble

Io

NASA Gallileo Image at: http://www.lpi.usra.edu/publications/slidesets/ss_tour/slide_23.html

Io

• About the size of our Noon

• HOT – tidal friction• Lots of Sulfur• Voyager detected• Yellow-brown color• Silicate lava – crust is

silicate in nature (strong; supports high mountains and deep crevasses; lava flows at temps too high for S)

NASA Gallileo Image at: http://www.lpi.usra.edu/publications/slidesets/ss_tour/slide_23.html

Io Galileo ImageTvashtar Catena

NASA Galileo image at: http://photojournal.jpl.nasa.gov/catalog/PIA02584

Io Amirani Lava Flow – Galileo Image

Largest active flow in solar system (~200-300 km)

Galileo image from http://photojournal.jpl.nasa.gov/catalog/PIA03533

• Plumes of sulfur / sulfur dioxide

• Long-lived (months)

• Geysers

• High – lack of atmospheric pressure and low gravity

• Old Faithful – 35 km high if on Io

Io

Voyager image at http://photojournal.jpl.nasa.gov/catalog/PIA01971

New Horizons flew past Io in late February 2007

New Horizons photos at http://pluto.jhuapl.edu/gallery/missionPhotos/pages/022707_1.htm l