Chapter 4: The Habitability of Earth Flashcards
What are the three types of rocks?
- Igneous rock. 2. Metamorphic rock. 3. Sedimentary rock.
What is Igneous rock made from?
From molten rock that cools and solidifies.
What are Metamorphic rocks?
Rock that has been structurally or chemically transformed by high pressure or heat that was not quite high enough to melt it.
How are sedimentary rocks made from?
By the gradual compression of sediments such as, sand and silt at the bottoms of seas and swamps.
How old is the Earth? Who was the first person to accurately give this number? What year?
4.55 billion years old. Clair Patterson in 1956.
What isotopes were used by Clair Patterson to find out the age of the Earth?
Combined the 238U-206Pb and 235U-207Pb system.
Earth’s surface has what two types of crust?
- Oceanic (Seafloor) crust. 2. Continental crust.
What is oceanic (seafloor) crust?
It is basalt in composition, and has a high density.
What is continental crust?
It is granite/rhyolite in composition (higher silica than basalt), and is less dense than oceanic crust.
What is subduction?
The process by which one plate moves under another and is forced or sinks due to gravity into the mantle.
What are faults?
Places where plates slip sideways relative to each other.
Why aren’t continental crusts moved into the core?
Because they are less dense.
What are the three types of plate boundaries?
- Divergent plate boundaries. 2. Convergent plate boundaries. 3. Transform faults.
