Exam 1 Review Flashcards
(50 cards)
Explain one key theme of Geology
The Earth is a planet, as in it interacts with the systems around it and provides a space for species to live on
How old is the Earth?
4.5 billion years old
How old is the universe (ex: when did Big Bang happen?)
14 billion years old
Explain one way the Earth has undergone profound change
The shift in magnetic field impacts ozone degradation acceleration and the variety of processes the Earth can carry out including weather and climate
What is the Geocentric Model?
Proposed in the Middle Ages, it stated that the Earth was the center of the Universe and everything else revolved around it
What is the Heliocentric Model?
Proposed in the Renaissance Era, it stated that the Earth revolved around the sun along with the other planets in our solar system
What helped support the Heliocentric Model and why?
In the 1600s Newton explained gravity which explained how our planet can stay in orbit and revolve around the sun at the same time (centripetal force)
T/F Helium and Hydrogen were the first elements to form when the universe was created
True
What are nebulas?
An enormous loud of dust and gas that acts as a nursery for new stars
How does a solar system form?
The collapsing of a nebula results in intense pressure and heat, causing gravity to pull debris from the nebula on the outside of a disk. Rocks and debris collide together to form planets that are still cooling down from the heat of the explosion.
How are planets formed?
While the nebula is collapsing or has collapsed, there is still remaining heat that is continuously melting the planetoid and molding it into a “spherical” shape until it cools and hardens
The Earth was originally a magma ocean T/F
True, it still needed time to cool down after the nebula collapsed
How are moons made?
Rocks/debris from the nebula collide with planets that have already formed and get trapped in the planet’s gravitational pull
When was Earth’s moon formed?
4.5 billion years ago
Planets in our solar system are typically composed of which elements?
Silicon and Oxygen, typically referred to as a silicate planet
Which 2 silicate planets share the same density?
Earth and Venus with a density of 4.4 g/cm^3
What does it mean for a planet to be differentiated?
It is a way to organize the various layers of the Earth based on depth and or the composition of elements that lay within each layer
The Inner Core typically has what elements? Are they dense?
Ni, Fe (Nickel and Iron)
They are incredibly dense due to the intense pressure and temperatures at the center of the Earth
Define the lithosphere and what kinds of rocks (Mafic, ultramafic, Silicic, etc.) can be found there
The lithosphere is the rigid crust at the surface of the Earth that we stand on. It has Silicic rocks (which is typically lighter in color)
Define the mantle and what kinds of rocks (silicic, ultramafic, Mafic, etc) reside there
The mantle is the hot magma layer below the lithosphere that contains Mafic rocks. The rocks here are denser than the ones that reside in/on the lithosphere
What is the difference between the inner and outer core?
The amount of temperature and pressure needed to keep rocks that reside there in place. The inner core is the densest layer that contains the highest pressure and temperature that keeps the inside metals fairly solid.
The outer layer of the Earth is liquid and convects heat that influences the geomagnetic core T/F
True
What is oceanic crust?
A dense type of crust that is fairly thin (7-10 km) and is found below sea level
What is continental crust?
Land crust that is incredibly thick and not super dense (breaks easily). Typically up to 70km thick, or deep. This is what we stand on.
