U3L1 Flashcards
Earth's Interior
list the 4 steps of the solar system’s formation
- a cloud of dust collapsed into a solar nebula
- began to rotate & flattened into a disk
- sun formed in the center
- particles collided and began to form planets. denser materials were closer to the sun due to its gravity.
identify the materials that formed earth
- dense rock
- metal
- collided dust & particles
list & explain three sources of energy in earth’s interior
collisions - kinetic energy from rocks colliding with earth transferred into heat energy
gravity - dense materials sinking to earth’s core had potential gravitational energy which transferred into heat energy
radioactive decay - unstable materials in earth’s interior broke down & released heat
explain how earth’s layers formed
(3 steps)
- the mixture of rock & metal started out uniform
- earth’s molten state allowed differentiation to occur, meaning that gravity pulled denser materials to the center and pushed less dense materials out
- processes that warmed the earth slowed down & the layers solidified
(diffrenation)
What is the crust?
Crust - thin, divided into two sections: the continental and oceanic. MADE of oxygen, silicon, and aluminum
What is the mantle?
Mantel- thick, middle layer. MADE of magnesium, less aluminum, and less silicon
What is the core?
Core - MADE of iron and nickel
- middle/center of the earth
What is the lithosphere?
- FIRST LAYER
- brittle and solid
- SOLID
What is the Asthenosphere?
- SECOND LAYER
- softer putty like
- soft mantle
- SOLID
What is the Mesosphere?
- THIRD LAYER
- flows slower than rock in the asthenosphere
- Harder dried out putty
- lower part of the mantle
What is the outer core?
- FOURTH LAYER
- liquid
What is the inner core?
- FIFTH LAYER
- solid
What are seismic waves?
Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on
seismographs.
How do scientists detect seismic waves?
With seismographs.
What are the two main types of seismic waves?
- Body waves - travel through earth’s interior layers ( S and P waves)
- Surface waves - travel only along the surface of the planet
What does the study of seismic waves reveal about Earth’s interior?
- P waves and s waves reveal layers and what the layers are made of
- shows how earth can shift
- shows that there is energy in the core
What are P waves?
- P waves are body waves
- P waves are also primary (meaning it is the first wave to come when a earthquake happens
- compressional waves
- P wave cause NO damage
- can travel through liquids and solids
What are S waves?
- S waves are body waves
- S waves are secondary (Meaning that second waves in an earthquake)
- transverse waves
- S waves DO cause damage
- can only travel through solids
What other methods and data add to the understanding of Earth’s interior?
- volcanic eruptions that produce xenoliths (chunks of the mantle)
- meteorites
- earth’s density & magnetic field
