-SS 4.6 billion yrs. old, Universe ~ 14 bill yrs

1. Condensed matter collided

2. Gravitational attraction (mass ↑, size ↓) 

3. Protosun collapsed (P ↑, T ↓)

-Nuclear Fusion (H→He)

4. Collision of particles to form planets!

Red Shift in distant nebulas (Doppler Shift) 

–Glow left over from explosion 

–Distant galaxies traveling away from us at great speeds 

1. Terrestrial Planets (earth-like)

-Primary composition: rocky & metallic

- Inner planets

2. Jovian Planets

-Primary composition: volitile substances

-H, He, H₂O, CO₂, ammonia, methane

*Why?  

-Volitile materials go away close to the sun b/c of heat

-sun pulls the densest thing closest

[image]

Theory = Hypothesis that have been tested 

multiple times and support observations 

»Atmosphere 

Water forms clouds that redistribute moisture 

»Hydrosphere 

The main reservoirs of water on Earth: 

»Oceans, lakes, rivers, groundwater, ice ... 

Which of these reservoirs contains most of Earth’s Freshwater? Total water? Fresh unfrozen? *1. Ice 2. Groundwater, 1. ocean 2. ice, 1. Groundwater 2. Lakes

»Biosphere 

Green blanket of plants 

Millions of animal and plant species 

coexist on Earth 

»Geosphere 

The solid earth: crust / mantle / core

-Isolated system

-No exchange of energy of matter beyond defined boundaries 

-imaginary

-Closed system

-boundaries allow exchange of energy 

-no exchange of matter

-Earth

-open system

-energy & matter can go in & out 

-island

"closed system" 

-energy IN as sunlight, OUT as heat

-matter, little matter leaves or enters atmosphere

-implications: waste has to stay, current resources are all we have

The average time H₂O spends in a reservoir 

residence time = volume/flow

ex. If a swimming pool

-contains 7,000 gal of H₂O

-inflow & outflow = 35 gal/day

residence time = 7,000/35 = 200 days

Continental Drift: based on observations of continental shape, & the geological record.

-Plates ARE moving, BUT the ocean material moves w/ it.

1960's 

1. Continents fit together

2. Old rocks line up

-mountain belts match

3. Coal in Antarctica

4. Fossil Plants & Reptiles

5. Glaciation in tropics

-ice directions from scour lines in rocks, south pole used to be in Africa 

»A. Divergent 

 -plumes of hot material giving you a volcano!

-plate riding on hot material

-burns into plate

[image]

Lithosphere = (Right under crust) strong "plate" layer, relatively cool & brittle

*Isostacy- Lithosphere floats on asthenosphere like ice burg

Asthenosphere = (last layer of crust) small amount of melt

Moho = (bottom of the crust) boundary marked by increase in seismic velocity 

Core-Mantle boundary 

-Pushes rocks formed under normal magnetism away from ocean spreading center ← goes back & forth

-makes it so you can only test one area in the bands & not the whole ocean

Because it:

-protects us from sun

-acts like a bar magnet

-poles are able to switch S=N & N=S

-caused by Earth's iron/nickel core, outer core solid, inner core liquid, there's a diff of rotation between cores

»a) Crustal Topography 

»b) Paleomagnetism, Crustal Age 

–Magnetic Reversals (104to 106year intervals) 

–Age of Ocean Floor 

Oldest Rock --200 million years 

–Polar Wander Curves 

»c) Location of Earthquakes and Volcanic Eruptions 

»d) Hot Spot Tracks 

a) warping/stretching of Pangea

-Volcanic matter begins pushing up Earth

b) rift forms

-continental matter breaks up oceanic crust forms, some H₂O.

-Naturally occuring

-inorganic/solid

-ordered internal molecular structure

-Definite chemical composition 

(whole earth)

Iron 32.4% weight 

Oxygen 29.9%

(crust weight)

Oxygen 46.6%

Silicon 27.7%

(crust volume)

Oxygen 94.05%

Silicon 0.88%

-Valence e^- are free to migrate among atoms

-weaker & less common than ionic or covalent bonds

Luster

-appearence in reflective light

-metallic/non-metallic

Color

-unreliable

-highly variable due to slight changes in mineral chem

Streak

-color of mineral in its powdered form

-helpful in distinguishing forms of the same mineral

Hardness

-Mohs hardness scale

Cleavage

-breaks along a plane of weak bonding 

-produces flat, shiny surfaces

-described by resulting geometric shapes

*# of planes

*angles between adjacent planes

Fracture

-no cleavage when a mineral is broken

Specific gravity

-ratio of the weight of a mineral to the weight of an equal volume of H₂O

-avg. 2.7

Others

-magnetism

-rxn to HCl

-malleability

-double refraction

-taste

-smell

-elasticity

Oxygen is much larger that Silica 

Tetrahedraforms with 4 O’s per SI (packed in middle)

Silicon-Oxygen Tetrahedron 

Close packing of oxygen 

Silicon fits in holes 

Charge on SiO4is -4

silicates

-most important mineral group

*comprise most of rock-forming minerals

*very abundant, due to large amounts of Si & O.

Plutonic are intrusive, they cooled slowly @ depth

Volcanic are extrusive, they erupted & quickly cooled

Aphanitic: fine grained 

Phaneritic: course grained 

• Crystals can be identified without a 

microscope 

Pegmatitic: Exceptionally coarse grained 

• Crystals > 1 cm diameter 

• Form in late stages of crystallization 

Pyroclastic:ejected volcanic fragments 

• Visually similar to sedimentary rocks

Porphyritic 

   Increase temp

-↑ heat, ↓ melts

Decrease pressure

-most solids take up less space than their melt

- ↑ pressure in mantle prevents melting

-If pressure ↓ rock melts

↑ H₂O

-A wet rock melts @ ↓ temp than a dry rock

- H₂O allows ions to move around

(During crystallization, the composition 

of the liquid portion of the magma continually changes) 

• Composition changes by removal of elements by earlier-forming minerals 

• The silica becomes enriched in the melt as crystallization proceeds 

• Minerals in the melt can chemicallyreact and change

Magmatic differentiation 

• Separation of a melt from earlier formed crystals to form a 

different composition of magma 

Assimilation 

• Incorporation of surrounding host rock into a magma 

Basaltic magmas 

• Most from partial melting of ultramaficmantle rocks 

• Form at mid-ocean ridges by decompression melting or at subductionzones 

• With upward migration, confining pressure ⇓thus melting temperature⇓ 

• Large outpourings of basaltic magma are common at Earth’s surface 

Andesitic magmas 

• Interactions of mantle-derived basaltic magmas and silica-rich crustal rocks 

• May evolve by magmatic differentiation 

Granitic magmas 

• Commonly a crystallization end product of andesitic magma 

• High in silica 

– more viscous than other magmas 

– lose their mobility before reaching the surface 

– Tend to produce large plutonic structures

↑ silica, ↑ viscosity, ↓ temp= explosive!

↓ silica, ↓ viscosity, ↑ temp = not as explosive

Shield volcano 

flows down gradually builds

stratovolcano

cascades "normal" volcano

cinder cone

need H₂O present, even on all sides

Ash fall: evenly covers hills & valleys (ex. snow)

Surge: thicker (ash) in valley, think on hills

Ash flow: think in valley, absent on hills

Mudflows:

-snow covered volcanic slopes rapidly melt

-can cause mass damage & death

-picks up debris which can cause even more damage

Gases

Steam

Climate change

-CO₂ long term warming

-SO₂ & ash keep solar radiation from hitting the planet (may enhance O₃ depletion)

-Active = erupted within recent history

-Dormant = Fresh looking flow

-Extinct = no evidence of activity, no driving force

-Volcanic precursors

-earquakes

-temp, & gas emitted

-Uplift & tilting

earthquakes

gas emitted

The index of eruption size

0 = low 8 = high

• Any object on a slope will tend to move 

down the slope due to gravity 

• force = mass x acceleration 

= (Mass of rock & soil) x 9.8 m/sec2 

• This force acts vertically

-sheer stress

• Slope 

–Angle of Repose 

• Moisture Content 

–Reduces friction:Pushes grains apart 

–Frost heave: Expansion / Contraction 

• Grain Size and Composition 

–e.g. Expanding clays 

• Vegetation: Can increase friction in shallowslides 

• Earthquakes 

–Shaking

Finer, rounder particles –gentler 

slope 

Grain Size: 

Angle of Repose 

• Composition 

– Clays --often slide 

– Sand --fairly stable 

– Gravel --stable 

• Shape 

– Round  -less stable 

– Irregular –more stable 

Material slides if steeper 

than the angle of repose 

Coarse, irregular 

particles –steeper slope 

Largest boulders 

typically reach the 

bottom of a talus slope 

or rockfall: 

Small rocksget caught 

in spaces between 

large rocks as they 

tumble. 

Large rockseasily roll 

over areas of smaller 

rocks to reach bottom of 

slope. 

Rotational

Translational

Block Slide

Fall

Topple

Debris flow

Debris avalanche 

Earthflow

Creep

Lateral Spreads

•Large Rain Storms:water 

• Development:water, slope steepened, load 

• Natural Erosion undercuts slope: 

steepened 

• Earthquakes:shaking 

• Volcanic Eruption:water, new loose material 

 Drain hillslopes 

–Reduces weight and increases friction at base of 

slope 

• Remove portion of slope that is likely to slide 

• Avoid undercutting steep slopes 

• Bolt slope together 

• Avoid developing areas with high slide risk