Lecture Quiz #1 (Chps. 1-3)

Question 1

Chp.1: What is geology? What is environmental geology?

Answer 1

study of rocks, the relationship between humans and the Earth (what effect have we had?)

Question 2

Chp.1: Haiti v. the Dominican Republic

Answer 2

Haiti is very barren and brown (overpopulation and overconsumption of resources, whereas the DR is green and foresty (better use of resources)

Question 3

Chp.1: Age of the Earth

Answer 3

Earth is 4.57 Billion years old

Question 4

Chp.1: What is geologic time? What is it based on?

Answer 4

Part of Earth’s history based on the geological rock record (fossils)
- ex. the first appearance of life on Earth
- ex. formation of Earth’s mountains

Question 5

Chp.1: What is a population bomb? What is the doubling time equation?

Answer 5

Population bomb is a high growth rate (leading to worries of overpopulation).
- Doubling time = 70/current population growth rate (percentage)

Question 6

Chp.1: What were trilobites? How does their story relate to population growth?

Answer 6

One of the most successful organisms ever in terms of diversity and population (similar to humans in that sense)
- despite their population dominance, they went extinct 251 million years ago

Question 7

Chp.1: What is an open system? What is a closed system?

Answer 7

O system in a system in which energy can be transferred between the system and its surroundings
- C system is the opposite

Question 8

Chp.1: What is the overshoot day?

Answer 8

The day in which humans will have used up all of the resources currently available on Earth :)

Question 9

Chp. 2: What are the layers of the Earth?
- Name a characteristic of each

Answer 9

1) Crust: the outermost top part, what we see everyday
2) Mantle: contains the lithosphere (outermost crust layer) and the asthenosphere (hot & slow flowing layer of relatively weak rock)
3) Outer core: liquid, produces Earth’s magnetic field
4) Inner core: solid, as pressure increases so does the melting point

Question 10

Chp. 2: How do we know what the thickness and composition of the layers of the Earth?

Answer 10

Seismology (study of earthquakes); the seismic waves move through material at different rates, which allows scientists to see the layers inside the Earth’s crust

Question 11

Chp. 2: What is a P-Wave? What’s an S-Wave?

Answer 11

P-wave: can travel through all materials (i.e. gas, water, air), are faster, and are able to be heard. Moves in an up and down motion
- S-wave: CANNOT travel through liquid, moves in a horizontal motion, slower

Question 12

Chp. 2: Difference between oceanic and continental crust?

Answer 12

Oceanic: more dense, mainly composed of heavy minerals

Continental: less dense, varying thickness, varying mineral composition

Question 13

Chp. 2: What is the lithosphere?

Answer 13

the part of the crust that we will on, outermost part of the crust

Question 14

Chp. 2: What is the asthenosphere?

Answer 14

underneath the lithosphere, it’s what the plate tectonics float on, acts like a hot plastic

Question 15

Chp. 2: What are ophiolites?

Answer 15

A piece of ocean crust/mantle that gets obducted rather then subjected (above ground rather then under)

Question 16

Chp. 2: what do lithospheric plates do?

Answer 16

creates earthquakes and other seismic activity that can be seen on the Earth’s crust (i.e. volcanos)
- vary in size
- overtime are created and destroyed

Question 17

Chp. 2: what is the continental drift?

Answer 17

the lithospheric plates moving over the asthenosphere

Question 18

Chp. 2: what are the 3 kind of plate boundaries? what do they do?

Answer 18

1) divergent: lithosphere is being produces as plates are moving away from each other (CREATION of plates)
2) convergent: occurs where plates collide (destruction of plates)
3) transform: occur where the edges of two plates slide against each other

Question 19

Chp. 2: what are subduction zones?

Answer 19

where one plate sinks beneath another and is destroyed (WHERE BOUNDARIES HAPPEN?)

Question 20

Chp. 3: characteristics of a mineral (5)

Answer 20

1) solid
2) naturally made
3) made of the same thing throughout
4) strutural component is consistent
5) well-defined chemical composition

Question 21

Chp. 3: most abundant mineral(s) in earth’s crust?

Answer 21

Feldspars

Question 22

Chp. 3: what’s the difference between a mineral and a rock?

Answer 22

minerals are naturally occurring while rocks are made of minerals

Question 23

Chp. 3: what are Igneous rocks?

Answer 23

made from MAGMA
- either INTRUSIVE (formed underground) or EXTRUSIVE (formed on the surface)

Question 24

Chp. 3: what is fractional crystallization?

Answer 24

change in melt chemistry from mafic (dark) to felsic (light)

Question 25

Chp. 3: what are Sedimentary rocks?

Answer 25

rocks that are formed through the erosion of igneous and metamorphic rocks. Tend to kind of look like a bunch of stuff cobbled together (maybe not as smooth as other rocks)
- clastic
- chemical
- biochemical

Question 26

Chp. 3: what are clastic rocks? how are they related to sedimentary rocks?

Answer 26

compacted rock cemented with different sediments picked up during its formation
- porous rocks filled with fossil fuel, water

Question 27

Chp. 3: what are chemical and biochemical rocks? how are they related to sedimentary rocks?

Answer 27

chemical: need to identify the minerals in the rock (looks more like a “normal” rock?)
biochemical: has something living in it (like a fossil)
- an example would be coal

Question 28

Chp. 3: what are metamorphic rocks?

Answer 28

rocks that are formed in areas with high pressure (such as subduction zones)

Question 29

Chp. 3: what is needed (at some level) for metamorphism?

Answer 29

pressure, temperature, and convergent boundaries

Question 30

Chp. 3: what are the 3 most important geological laws? explain them.

Answer 30

1) law of crosscutting relationships: a rock is younger than any other rock that it cut
2) law of original horizontality: when originally deposited, sedimentary layers are nearly horizontal
3) law of superposition: IF sediments layers have not been overturned, then the bottom layer is the oldest and the top the youngest