Planet Earth Midterm

Sediments
Fragments being transported
Sediments/Diagenesis

a.sediments are being deposited

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b. diagenesis-the accumulation compaction cementation

accumulation(where there deposited)

a.oceans

b.lakes

c.deltas

d.shoreline

e.glaciers

f.deserts(wind)

g.riverbed

h.mudslides

comapaction and cementation

a.calcite

b.CaCo3

c.quartz

d.SiO2

1. these form layers, beds, and strata, sorting melting process glaciers do not form sorting because it drops everything when melting also landslides do not sort materials.

Clastic vs. non-clastic

Clastic

sediments are made out of fragments you can see it with the naked eye

Clastic vs. non-clastic

non-clastic

a.rocks that crystalize in water

b.chemical or biochemical precipitate

c.biochemeical means an animal is involved

 

Parrallel bedding

__________

B__________

A__________

 

graded bedding sorted large to small vertically and horizontally

cross bedding
occurs do to currents but mainly waves maken layers between horizontal layers
ripple marks


caused by waves and currents. sediments that represent how the waves pushed them to the shore line

mudcracks

 

a.shallow water

b.wet sediments-shrink

 

 

 

c. cracks remain as part of te rock

d. water deposits between these cracks tells us it was a shallow water enviroment

Fossils

a.remains of a once living organsim

b.body parts or evidence of it’s activity has to be atleast 1,000 years old

c.not only the animal parts buts its activity

coprolite-fossilzed feces (most sought sought after fossil)

1.very revealing of life on earth

2.used to determine age history of earth

3. 99.9% percent of fossils are sedimentary

dark black sedimentary rocks means it has alot of organic content.

black=organic

light red =alot of iron

Geologic Cycle/geo principles

-important in the history of the earth

James Hatton(scottish farmer)

a. Things come up from the ocean they come to the form and then erode back down.

b. a cycle

Geological Cycle

a.everything on the earth is cycling

b. Rocks–>sediments–>sediments

6 Principles

Uniformitarinism

a. the present is the key to the past.

b.all processes that are on the earth today have existed and acted the same way in the past

6 Principles

Orginal Horizonatality

a. when sedimentary rocks form and are undisturbed expects them to be horizontal

6 Principles

Superposition

a. the one on the bottom and is undisturbed is the oldest the top is the youngest

 

__________

D__________

C__________

B__________

A__________

6 Principles

Cross-Cutting Relationships

a. intrusion into something tells us about age

b. if it cross cuts it’s younger because it intrudes something that is already there

 

____________

D____________

C____________

B____________

A____________

6 Principles

Inclusions

 

a. the inclusions represents an older source

 

 

 

____________

____________

____________

____________

____________

6 Principles

Igneous/Sedimentary

_____________

_____________

_____________

_____________

_____________

 a. if its an igneous intrusive (plutons)it’s a sill

b. Volcanic (E) is younger because it has to be there to cover the lave than D

c. F is the youngest

6 Principles

Igneous/Sedimentary

Extrusive(Volcanic)

extruve on the surface

6 Principles

Igneous/Sedimentary

Intrusive(plutonic)

 

a. instrudes in the surface inside the earth

Mafic rock= Gabbro

Ultra Mafic=Perodite

ways we know whats inside the earth

evidence

1.eruptions

2.erosion

3.12km (drilling)

4.seismic waves(earthquakes waves)

ways we know whatsinside the earth

1. certain constant change

2.5000 degrees C center of the earth

3.density 18km in center

4,000,000 in the center

5.volcanis erruption is evidence of what is in the center of the earth

6.erosion

7.drill a hole

8.maxium density to drill is 12km

9. Granite is uner the continents and Basalt is under the ocean

in the outer core heat wins over pressure and makes things liqu
in the inner core pressure wins over heat and makes things solid
earths structure

1.crust

2.mantle

3.outter core-liquid

4. inner core-solid

Geological Time

Relative Time

Principle Cont.

Unconformity

a.reps erosion not deposition, abscence of deposition

b. tells about the depth of the ocean

 

Unconformity

a. tells us about time, there was an interruption

b.tells us depthbetween limestone and sandstone the water becomes less, the amount of what decreases, its exposed and becomes shallow.

b. deep shallow

c. conglomerate shallow depth

d. limestone deepest

unconfomrity can be divided in 3 types

 

1.angular

2.discomformity

3.non-conformity

angular unconformity

1. layers deposited

2.metamorphic

3.exposure

4.depostition

discomformity
Transgression/regression conformity

a. sea level rising and falling

 

Transgression conformity

a. the sea invades the land

Two causes: glacieation and plate movement

1.when glaciers melt

2.land elevates

Regression

a. the sea level drops

1.when glaciers form

2.land goes down

Facies

1.horizontal

2.vertical

William Smith (Engineer)

discovered radio activity

a. recognized that each layer contained distinctive fossilsvertically

b.fossilis change through time correlation

1.age equivilance through fossils

-certain isotopes spontaneously decay by themeselves giving out paricles by omitting alpha, betta, and gamma waves and becoming stable

-they are stable because they are decaying themselves