EARTH

‘SIDE VIEW’

‘TOP VIEW’Solar System on outsideof Orion Arm (25,000 light years from centre)

100,000 ly

Nebular hypothesis Important theorists: Emanuel Swedenborg (1734), Immanuel Kant (1755), Pierre-Simon

Laplace (1796), Victor Safronov (1972) – Solar nebular disk model (SNDM)

Evidence: observations systems at varying stages

1. Nebula: Giant Molecular Cloud (GMC) results from collision(s) or explosion of dying star

3. H and He condense into Sun4. Disk of matter (many elements) around sun5. Disk slowly accretes into clumps (planetesimals)

that also contain heavier elements6. planetesimals planetoids

planets and satellites

Hubble Space Telescopeview of a new solar system1500 l-y away in the Orion Nebula

Eons, Eras, Periods and EpochsSuperposition: youngest rocks superimposed on older rocks “Relative time”

Dating by radioactive isotopesHalf-life: time for ½ of unstable isotopes to decay “Absolute time”

Uniformitarianism:“The same physical processes active in the environment today have been operating throughout geologic time” Hutton (1795), Lyell (1830)

Source: University of Calgary

Red ovalsindicatemajorextinctionevents:when extinctionrate greatlyexceeds speciationrate

The Earth incross-section

Upper mantleand lithosphere

Mountain massesdisplace mantle material

Isostatic adjustmentdue to loss of massby erosion

Deformation fromsediment load

ISOSTASYElevation of tectonic plates determined by density/thickness

MineralA natural, inorganic compound with a specific chemical formula and a crystalline structure

Examplessilicates (quartz, feldspar, clay minerals), oxides (eg., hematite) carbonates (eg., calcite)

An assemblage of minerals bound together

• Igneous (solidify & crystallize from molten magma/lava)

• Sedimentary (settling & cementation)

• Metamorphic (altered under pressure)

• from magma (molten rock beneath the surface)

• intrusive or extrusive (from lava)

Laccolith

Dike

Sill

Batholith

plutons

Existing rock or organic material is digested by weathering, picked up by erosion, moved by transportation, and deposited at river, beach and ocean sites.

Lithification follows (cementation, compaction and hardening)

Laid down in horizontally-layered beds

Conglomerate largest clastsSandstone sand cemented

togetherSiltstone derived from siltShale mud/clay compacted into

rock

Limestone calcium carbonate, bones and shells cemented or precipitated in ocean

watersCoal ancient plant remains

compacted into rock

note the shells

Any type of rock is transformed, under pressure and increased temperature

Harder and resistant to weathering

Produced from any rock type by:•Compressional forces due to plate collisions•Regional and contact metamorphism

Shale Slate

Granite Gneiss

Basalt Schist

Limestone, dolomite Marble

Sandstone Quartzite

Crustal Movements

•Continents are adrift due to convection currents in the asthenosphere

•Mantle movements result in platemigration

•225 M BP: Pangaea

Continents Adrift

Age of mid-oceanic ridge magnetic stripes

Subduction zones

“Ring of fire”

Age and thickness of oceanic crust

Fossil Record (plant and animal)

Distribution of marsupials vs. placentals

Mid-oceanic ridge magnetic stripes

See: http://www.scotese.com/sfsanim.htm (animation)

Divergent Boundaries (constructional)

Convergent Boundaries (destructional)

Transform Fault Boundaries

URL: http://pubs.usgs.gov/publications/text/Vigil.html

Source: USGS

Earthquakes and Volcanoes

The technique of _____ involves the measurement of decaying elements and stable end products.

a) radiometric dating

b) relative dating

c) superposition

d) punctuated equilibrium

e) uniform dating

The technique of _____ involves the measurement of decaying elements and stable end products.

a) radiometric dating

b) relative dating

c) superposition

d) punctuated equilibrium

e) uniform dating

Place the major concentric layers of Earth in order from outermost to innermost.

a) mantle > outer core > inner core > crust

b) inner core > outer core > mantle > crust

c) outer core > crust > inner core > mantle

d) crust > outer core > inner core > mantle

e) crust > mantle > outer core > inner core

Place the major concentric layers of Earth in order from outermost to innermost.

a) mantle > outer core > inner core > crust

b) inner core > outer core > mantle > crust

c) outer core > crust > inner core > mantle

d) crust > outer core > inner core > mantle

e) crust > mantle > outer core > inner core

The process of cementation, compaction, and hardening of sediments into sedimentary rock is called _____.

a) carbonation

b) geomagnetic reversal

c) lithification

d) isostasy

e) metamorphism

The process of cementation, compaction, and hardening of sediments into sedimentary rock is called _____.

a) carbonation

b) geomagnetic reversal

c) lithification

d) isostasy

e) metamorphism

The most common extrusive igneous rock is _____.

a) sandstone

b) basalt

c) granite

d) gneiss

e) limestone

The most common extrusive igneous rock is _____.

a) sandstone

b) basalt

c) granite

d) gneiss

e) limestone

Pangaea is the name given to

a) the part of California west of the San Andreas fault that is moving into the Pacific Ocean.

b) the period of geologic history that predates modern life forms.

c) a rift valley in east Africa where a new ocean is forming.

d) the name of a previous supercontinent thought to have broken into several plates.

e) the larger feature that makes up the Hawaiian Islands via hotspot volcanism.

Pangaea is the name given to

a) the part of California west of the San Andreas fault that is moving into the Pacific Ocean.

b) the period of geologic history that predates modern life forms.

c) a rift valley in east Africa where a new ocean is forming.

d) the name of a previous supercontinent thought to have broken into several plates.

e) the larger feature that makes up the Hawaiian Islands via hotspot volcanism.

The interconnected mountain chain on the ocean floor is built by upwelling flows of magma in a process called _____.

a) trench widening

b) metamorphism

c) sea-floor spreading

d) isostasy

e) subduction

The interconnected mountain chain on the ocean floor is built by upwelling flows of magma in a process called _____.

a) trench widening

b) metamorphism

c) sea-floor spreading

d) isostasy

e) subduction

A batholith is most directly associated with

a) intrusive igneous rocks.

b) chemical sedimentary rocks.

c) relative-age dating.

d) extrusive igneous rocks.

e) metamorphic rocks.

A batholith is most directly associated with

a) intrusive igneous rocks.

b) chemical sedimentary rocks.

c) relative-age dating.

d) extrusive igneous rocks.

e) metamorphic rocks.

The collision of India and Asia to form the Himalayas is an example of a _____ plate boundary.

a) drifting

b) convergent

c) divergent

d) transform

e) upwelling

The collision of India and Asia to form the Himalayas is an example of a _____ plate boundary.

a) drifting

b) convergent

c) divergent

d) transform

e) upwelling

Subduction is most likely to be located _____.

a) at the collision of two pieces of continental crust

b) underneath mid-ocean ridges

c) within the outer core

d) at the collision of oceanic and continental crust

e) in the middle of ocean basins

Subduction is most likely to be located _____.

a) at the collision of two pieces of continental crust

b) underneath mid-ocean ridges

c) within the outer core

d) at the collision of oceanic and continental crust

e) in the middle of ocean basins

A map of global volcanoes and earthquakes reveals that they are most commonly found

a) along plate margins.

b) in the center of plates.

c) at hot spots.

d) along mid-ocean ridges.

e) in Australia.

A map of global volcanoes and earthquakes reveals that they are most commonly found

a) along plate margins.

b) in the center of plates.

c) at hot spots.

d) along mid-ocean ridges.

e) in Australia.

The location of the Mohorovičić discontinuity is best described as residing between

a) continental crust and oceanic crust.

b) the outer core and inner core.

c) Gondwana and Laurasia.

d) the Nazca plate and the South American plate.

e) the crust and the mantle.

The location of the Mohorovičić discontinuity is best described as residing between

a) continental crust and oceanic crust.

b) the outer core and inner core.

c) Gondwana and Laurasia.

d) the Nazca plate and the South American plate.

e) the crust and the mantle.