week one questions Flashcards
What is the crust?
The crust is the outer layer of the earth, mainly made of oxygen and silicone. It is fully solid.
What is the mantle?
The mantle is composed of two parts, the upper mantle and the lower mantle. The upper mantle is liquidy, but very slow to flow. It is made up of olivine, mainly. The lower mantle is solid and olivine but with more minerals.
What is the core?
The inner core is solid and made of iron and nickel. The outer core is liquid.
What is the lithosphere?
The lithosphere is the crust and the top mantle.
What is the asthenosphere?
The asthenosphere is the part of the earth that can flow, below the lithosphere.
How is continental crust different from oceanic crust?
Continental crust is much thicker, 20-25 miles, and ocean crust is more like 4 miles.
What is the difference between a hypothesis and a theory?
A hypothesis has no proof behind it. It must be tested. If it is tested and nothing contradicts it, it becomes a theory.
What is uniformitarianism?
Uniformitarianism is the idea that the physical processes that happen on earth today are the same as which occurred in the past.
How did the earth get its layers?
As the earth spun, the densest materials went to the inside.
How did the earth get its atmosphere?
How did the earth get its oceans?
How did the earth get its moon?
A large planetary body- around the size of mars- ran into the earth, which broke off a chunk.
What is the nebular hypothesis?
The Nebular Hypothesis suggests that our solar system was created by a large cloud of dust and gas that spun around. Due to gravity, the densest parts went to the middle and the gases went to the outside. This is why the rocky planets are on the inside and the gassy ones are on the outside.
What are some common elements in all the earth?
Earth : iron (35%), oxygen (30%), silicon (15%), magnesium (13%), nickel (2%), sulfur (2%) and other elements (3%).
