• Today– Hot Spots– Past Plate Motions– Review TEST 1– LAB: Describing Minerals

• Wednesday– TEST 1– Chemistry of Minerals– READ Chapter 5

• Next Monday– Rock Forming Minerals– LAB Identifying Minerals

Hot Spots

Global Distribution of Active VolcanoesSource: http://www.volcano.si.edu/world/location.cfm

09_16b.jpg

04_22.jpg

04_21.jpg

04_23b.jpg

04_23a.jpg

animation

04_22.jpg

Past Plate Positions

Dating the Sea Floor (Fig. 4.11)

animation

Magnetometer Fig 3.24a

Magnetic Field Strength near PNW Coast Fig 3.24b

Magnetic Field

Strength Portland

Source: http://wrgis.wr.usgs.gov/docs/gump/portland/portland.html

Magnetism of a Lava Flow Sequence (Fig 3.25)

Magnetic Field Flips Fig. 3.26

Magnetic Reversal Time Line(Fig 3.27)

Geomagnetic TimescaleFig. 3.30c

Cause of Reversals? Fig 3.27

http://www.es.ucsc.edu/~glatz/geodynamo.html

Fig 3.28

animation

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Dating the Sea Floor (Fig. 4.11)

animation

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Animation of Continental Drift

Cause of Plate Tectonics? Fig. 4.32

Convection in Mantle Fig. 4.28

C_12.jpg

C_16.jpg

Ridge Push and/or Trench Pull Fig. 4.29

Super Continent Cycle?

http://www.gps.caltech.edu/~gurnis/Movies/Science_Captions/aggdisp.html

http://www.uwgb.edu/dutchs/platetec/plhist94.htm#750my

West Coast

TectonicsFig 4.19

PNW Earthquakes

& Plates

3-D view: http://spike.geophys.washington.edu/SEIS/EQ_Special/WEBDIR_01022818543p/hypos.html

Evidence for Past Subduction Zone Earthquakes?

What happens during subduction

zone earthquake? Locking and Bulging

GPS: ½ in/year

Rebound

uplift subsidence

Ghost Forest

And deposition by tsunami

Coastal evidence

of subduction

zone earthquake

s

Peat Layer topped by Tsunami Sand-Oregon

Orphan Tsunami in Japan Jan 29, 1700

Last Subduction Zone Earthquakes

• January 26th 1700

• Coast Line from Vancouver Island to Northern California subsided approx. 6ft.

• M9! (100 times Nisqually earthquake)

How frequent?How frequent?One every 300-800 years. Last one 300 y. One every 300-800 years. Last one 300 y.

a.a.

TEST 1

• Chapters 2, 3, 4, prelude, interlude A & E

Minerals

Crystals Grains in Rocks

Quartz Fig. 5.15

Metallic vs. Non-Metallic Luster Fig. 5.17

Streak Fig. 5.16

Table 5.1

Cleavage Fig. 5.19

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Crystal Shapes Fig 5.5

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Conchoidal Fracture Fig. 5.20

Fizz Test (Fig. 5.22)

Major Classes of Rock- Forming Minerals

Class Defining anion(s) Examples

Native elements

none (no charged ions) gold (Au), copper (Cu), sulf ur (S), diamond (C), graphite (C)

Halides ions of chlorine (Cl-), fluorine (F-)

halite (NaCl), fluorite (CaF2)

Sulfides sulfide ion (S2-) pyrite (FeS2), galena (PbS), sphalerite (ZnS)

Oxides oxygen ion (O2-) hematite (Fe2O3), magnetite (Fe3O4), corundum (Al2O3)

Hydroxides hydroxyl ion (OH-) goethite [FeO(OH)], gibbsite [Al(OH)3]

Phosphates Phosphate ion (PO4)3- Apatite (Ca5(PO4)3)(F,Cl,OH)

Turquoise CuAl6(PO4)4(OH)84H2O

Sulf ates sulf ate ion (SO4)2- gypsum (CaSO42H2O),

barite (BaSO4)

Carbonates carbonate ion (CO32-) calcite (CaCO3),

dolomite [Ca, Mg(CO3)2],

Silicates silicate ion (SiO44-) quartz (SiO2)

olivine (Mg2SiO4)

For Wednesday 1/21

• TEST 1– Chapters 2, 3, 4, – prelude, interlude A & E– 377-379

• Reading-Chapter 5 Minerals