GEOL 109 - BYU - FINAL REVIEW

Io has tidal forces that pull on the moon while it orbits Jupiter and it creates friction of the surface that allows for activity of volcanism to continue

• Io has an eccentric and elliptical orbit

• it is pulled into different shapes based on its proximity and position to Jupiter

• causes tidal heating through friction

Few geologic processes driven by internal energy are still active on the small inner planets (like the Moon and Mercury), whereas Io, another small "planet," has a very young surface and active volcanoes. Why?

If there is a heavily cratered surface its older, if its younger its smoother.

Impact cratering is a fundamental geologic process. Describe a generalized cratering history for a planet. Make sure you explain how the number of impact craters on a planet's surface is related to its age.

It accreats and while it heats up it has differentiation, the iron moves to the core the silicates move to the mantle and as it goes outward the materials become lighter in density

Describe a typical thermal history of a silicate planet. If there are significant deviations from this scenario describe them

No atmosphere's change. for example earth had a lot of carbon dioxide and as life and certain rocks came about it added more oxygen to the atmosphere

Once an atmosphere is outgassed, does its composition or mass stay constant? Give examples of some changes in planetary atmospheres

It has to do with heat and where it comes from. Earth has a lot of internal heat which is why it still has a lot of tectonic activity today.

Why are some planetary bodies tectonically active today and others are not?

Because of their closeness to sun the less dense materials dissipate faster than the outer planets

solar thermal gradient

Why are the inner planets dense and rocky when compared to the outer planets?

Old/young surface

There is volcanisms/not

Liquid/not

Density shows if its closer to sun/not and type of materials probably present

Is atmosphere thick/not

Color of atmosphere

it has a density of 5.3. Suppose that you had no other information about this planet. What can you infer about its present state and past geologic history from this photo?

condensed atmosphere of Pluto as it was blown off from Pluto

• probably methane from Pluto

How did the red terrain on Charon form? It lies at the moon’s north pole.

Older surface

Lots of impact craters

tectonic extension seen through the lines

fractures as opposed to mountains

no active flow features so not very tectonically active

low density may suggest that it is icy rather than rocky

low density means farther from the sun

Imagine that this photograph is our first close-up picture of an extrasolar planet called Incognita in the Alpha Beta system.

Incognita has a density of about 1.3 g/cm³.

We think that this solar system formed 5.6 billion years ago.

Suppose that you had no other information about Incognita. What can you infer about Incognita’s present state and past geologic history from this photo?

Planetary nebula - when medium sized star can’t hold onto their materials anymore and basically explodes

• occurs when medium sized star dies, like the sun

• it creates a cool cloud of dust and gas

How did this image form?

as basaltic lava cools and then contracts

• contraction creates ridge

How do these wrinkle ridges form?

T-Tari stage

sucks in material and shoots out of the poles

What is this?

Iron meteorite

• no stony evidence

What type of meteorite is this?

Stony - Chondrite meteorite

• chondorite= nodules that contain different materials (like olivine)

What is this?

Medium - no multiple rings so a bit bigger than 30 km

• not big enough to have rings

Older but more middle aged than ancient

• no ejecta blanket

• smaller impact craters around it

• steep walls

• flat floor

• material in the center

How large is this crater (on a relative scale)?

How old is the crater (on a relative scale?

Highlands (older, protrude against level of mare)

smooth area= Mare/lava plains (erases the older features)

impact carters

huge multi ring impact basin in the back

The highlands are older bc more craters

What terrains are in this image?

Which is older?

a: Crater rim/edge

b: small impact crater:

c: Flood plains/ mare

d: Sinuous rille

e: Wrinkle ridge

oldest : a (part of it is worn out)

c: wears out other features

e

b

d:cuts across the wrinkle ridge

What features are present in this image?

What are their relative ages from oldest to youngest?

Its older bc they are craters

extensional

What is the age of crater marked by yellow arrows compared to the others in the image?

What is the feature indicated by the red arrow?

Venus- does not have any signs of hydrologic system, but does have lots of volcanics

Lava flow & extensional tectonic features

What planet is this?

What created the sinuous channel and the bright straight lines?

Older than the surrounding stuff

• you can barely see it because it is covered by other craters

Palimpsest as the meteor hits it, the ice will go back into the planet which makes it more flat

How old is this light colored area?

How did it form?

EOLIAN DUNES, wind or eolian process

No

How do these landforms form?

Is this from the Moon?

Mars

• mud like ejecta planet

• impact may have melted some ice and caused a splatter pattern surrounding impact crater

What planet do rampart craters form on?

from dust and gas as the Sun heats up the comets interior and they evaporate

how do the bright streaks form?

Venus - they are pancake domes

What are these circular features?

• extensional features because they are long lines aka rilles

• older becasue impact craters appear on top of them

Explain the origins of the lineated terrain? Is it older or younger?

Earth, ice feature/polar cap

What is this feature and where is this

A and E are not

B, C, and D are

What types of tectonic features do the different letters mark?

Are they all plate boundaries?

Io Volcanoes

What are the dark features?

Europa - it broken up ice

What could make the chaotic area to the left of the center?

• found on Venus

• formed from interaction between Venus’s atmosphere and the impact crater

• Venus has lots of wind, so material spreads out

• Molten material from the impact

What planet are craters like this found? Why does this impact crater have long "bright" deposits extending downhill away from its right edge?

Sand dunes

It has eolian processes so wind and it has an atmosphere

What are the black linear features?

What do they tell us about the differentiation of the planet?

• Callisto

• heavily cratered so very old

• 4.5 million years old

Which planet’s moon is this? What is the surface age of this moon?

Saturn’s moon Enceladus

It has lots of smooth plains not a lot of craters meaning its young

• white and bright

• lots of cracks likely due to ice

• surface is young

• ice causes expansion, which leads to cracks

• colder because it reflects the light back and does not absorb it

What is the surface composition of this moon?

What is unusual about the surface of this small moon?

It is Saturn’s moon, Titan

• largest moon of Saturn

outer solar system its made of nitrogen

• thick nitrogen atmosphere

• hydrologic system of methane

What is the composition of this atmosphere?

Where is it in the Solar System?

a moon of Neptune

Atmosphere freezes and it forms these nitrogen poles while in winter

• it is frozen nitrogen ice, and hase water ice and carbon dioxide ice

• frozen version of Earth’s atmosphere

How does the bright material on the bottom half of Triton form?

it is neptune!

Methane

• takes in light

• absorbs spectrum from red and refelcts blue

Why is this planet blue?

Triton is larger b/c

• it has sufficient gravity, is round, thought to be a captured dwarf planet, has a retrograde orbit (opposite rotation)

• composition similar to pluto

Proteus is …

• an icy body

• was acquired later on

• does not have much gravity because it is not round

What are the important differences between these two bodies? Which one is actually larger?

• liquid flowing

• liquid methane

What process forms the dendritic pattern on Titan?

Extensions, as the ice cools it freezes it expands

• happens with lots of water planets

• ice is less dense than water

• ice takes up more space then liquid

• as it freezes, it expands

How did the tectonic fractures form on Pluto?

on venus!

• has things that are coronas- circular plains surrounded by belts

• Volcano.

• As it lifts up it extends everything around it

How did this radial pattern form?

Related to coronas form as mantle plume comes up through crust and as it cools it gets more dense and drains out of the center and sinks

What process is this feature related to?

Ice

What is the most likely composition of this surface?

A

line of volcanic cones

B

transform boundary

C

divergent boundary

D

convergent boundary

B

• oldest becasue it has the most craters

Which area of Enceladus is the oldest?

E

continental highlands