Lecture Quiz #1 (Chps. 1-3) Flashcards
Chp.1: What is geology? What is environmental geology?
study of rocks, the relationship between humans and the Earth (what effect have we had?)
Chp.1: Haiti v. the Dominican Republic
Haiti is very barren and brown (overpopulation and overconsumption of resources, whereas the DR is green and foresty (better use of resources)
Chp.1: Age of the Earth
Earth is 4.57 Billion years old
Chp.1: What is geologic time? What is it based on?
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
Chp.1: What is a population bomb? What is the doubling time equation?
Population bomb is a high growth rate (leading to worries of overpopulation).
- Doubling time = 70/current population growth rate (percentage)
Chp.1: What were trilobites? How does their story relate to population growth?
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
Chp.1: What is an open system? What is a closed system?
O system in a system in which energy can be transferred between the system and its surroundings
- C system is the opposite
Chp.1: What is the overshoot day?
The day in which humans will have used up all of the resources currently available on Earth :)
Chp. 2: What are the layers of the Earth?
- Name a characteristic of each
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
Chp. 2: How do we know what the thickness and composition of the layers of the Earth?
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
Chp. 2: What is a P-Wave? What’s an S-Wave?
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
Chp. 2: Difference between oceanic and continental crust?
Oceanic: more dense, mainly composed of heavy minerals
Continental: less dense, varying thickness, varying mineral composition
Chp. 2: What is the lithosphere?
the part of the crust that we will on, outermost part of the crust
Chp. 2: What is the asthenosphere?
underneath the lithosphere, it’s what the plate tectonics float on, acts like a hot plastic
Chp. 2: What are ophiolites?
A piece of ocean crust/mantle that gets obducted rather then subjected (above ground rather then under)
Chp. 2: what do lithospheric plates do?
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
Chp. 2: what is the continental drift?
the lithospheric plates moving over the asthenosphere
Chp. 2: what are the 3 kind of plate boundaries? what do they do?
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
Chp. 2: what are subduction zones?
where one plate sinks beneath another and is destroyed (WHERE BOUNDARIES HAPPEN?)
Chp. 3: characteristics of a mineral (5)
1) solid
2) naturally made
3) made of the same thing throughout
4) strutural component is consistent
5) well-defined chemical composition
Chp. 3: most abundant mineral(s) in earth’s crust?
Feldspars
Chp. 3: what’s the difference between a mineral and a rock?
minerals are naturally occurring while rocks are made of minerals
Chp. 3: what are Igneous rocks?
made from MAGMA
- either INTRUSIVE (formed underground) or EXTRUSIVE (formed on the surface)
Chp. 3: what is fractional crystallization?
change in melt chemistry from mafic (dark) to felsic (light)
Chp. 3: what are Sedimentary rocks?
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
Chp. 3: what are clastic rocks? how are they related to sedimentary rocks?
compacted rock cemented with different sediments picked up during its formation
- porous rocks filled with fossil fuel, water
Chp. 3: what are chemical and biochemical rocks? how are they related to sedimentary rocks?
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
Chp. 3: what are metamorphic rocks?
rocks that are formed in areas with high pressure (such as subduction zones)
Chp. 3: what is needed (at some level) for metamorphism?
pressure, temperature, and convergent boundaries
Chp. 3: what are the 3 most important geological laws? explain them.
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
