Introduction

Question 1

What are the two categories that geology is spilt into? Which came first

Answer 1

Physical geology (1st)
Historical geology

Question 2

What is the source of energy for internal processes coming from (2 places)?

• how did one of these sources come to be?

Answer 2

Heat from Earth formation
* hot, dense stuff f/collisions sank to become core

Heat from decay of radioactive isotopes

Question 3

What is the source of external processes?
what do internal processes produce?
ex of external processes

Answer 3

Sun
EQ, mt, volcanoes
Erosion, weather, climate

Question 4

Things that make up the hydrosphere

order f/makes up greatest majority–> least majority
include components

Answer 4

1. Oceans
2. Freshwater - glaciers/ice sheets, ground water, other (streams, lakes, etc)
3. Saline ground water and lakes

Question 5

Processes modifying earth surface

Answer 5

Tectonics
Action of water
Biological processes

Question 6

How old is the Earth?

Answer 6

4.6 billion years old

Question 7

Erosion

Answer 7

Physical removal of material by an agent like water, wind, ice

Question 8

How did the Earth acquire its layered structure? (3)

what were the rocky materials rich in?

Answer 8

heat that drives internal processes–iron and nickel melted and sank to form core

Chemical differentiation: buoyant magma rose and solidified as crust, rocky materials were rich in oxygen and silica

Chemical segregation created 3 layers- core, mantle, crust

Question 9

Composition of oceanic vs continental crust
* thickness
* rocks found
* composition

Answer 9

Oceanic: 7km thick, mafic (basalt and gabbro), iron and mg

Continental: heterogeneous composition, average of granodiorite, felsic, Si, 40-70 km thick

Question 10

Density of oceanic crust vs continental crust vs mantle

Answer 10

Oceanic: 3.0g/cm^3
Continental: 2.7g/cm^3
Mantle: 4.5g/cm^3

Question 11

Mantle composition (state of matter, composition, materials)
Layers of the mantle
What are the parts of the mantle? Mantle is stronger at ___

Answer 11

Solid, rocky shell, silicate materials

lower mantle, upper mantle> lithosphere and asthenosphere

Question 12

Composition of lithosphere (state of matter, temp, strength, comp, thickness)
what makes up the lithosphere

Answer 12

Solid, Cool, rigid, strong, 100km thick
Crust and uppermost mantle

Question 13

Composition of the asthenosphere (state of matter, strength, movement)

Answer 13

solid, weak, moves like silly putty, ductile, easily deformed

Question 14

Core composition (majority-least)
Avg density
outer core and inner core composition (state of matter, elements, movement, density)

Answer 14

iron, nickel, oxygen, silicon, and sulfur

Outer: liquid iron rich (molten) 11g/cm^3
Inner: solid dense metallic 13 g/cm^3

Question 15

What is the chemical composition of the earth vs physical composition

Answer 15

chemical: core, mantle, crust
physical: inner core, outer core, lower mantle, upper mantle>asthenosphere, lithosphere (oceanic crust, continental crust)

Question 16

Unformitarianism

Answer 16

processes acting on earth today operated in the past, present is the key to the past

Question 17

who created uniformitarianism

Answer 17

james hutton

Question 18

prodominant rock of upper mantle
what does the mantle have more of than the crust? describe the lower mantle

Answer 18

peridotite
iron and mg
rocks are hot and have gradual flow