Planet Earth Topic 4-10 Flashcards
What are the five layers of the earth
- Crust cool out most lure
- Upper mantle diols and together
- lower mantel partly melted consistency of taffy
- Outer core contains iron,nickel and is liquid
- Inner core sphere temperature of 6000*c
Who is Alfred Wegener
He is a scientist who thought all the contents were connected a really long time ago
What is some evidence Wegener used to support his theory
There are similarities in rock samples on both sides of the Atlantic Ocean also similar fossils found in the Himalayan mountains
What dose sonar mean when is it used
It stands for SOUND NAVIGATION AND RANGE bats use sonar to help nave hat through the dark if the night
Scientists used sonar what did they find out about oceans
Scientists found mountains on the ocean floor using sonar
What is the mid Atlantic ridge
A giant magnetic field that is in the middle of the ocean
What is the the theory of the sea floor spreading
They thought the sea floor was spreading the ocean floors ridges and rocks where getting farther apart
Define Diverging plates
Two or more plates move away from each other
Converging plates
Two or more plates colliding
What is the theory of plate tectonics
Evidence that earth crust is move
Who is Tuzo Wilson
A Canadian scientists who contributed to our understanding of the earths crust
What are convection currents?
A convention current is the flow result from the rise of warming materials and the sinking of cooler material scientist call the places where the two plates collide convergent or collision boundaries although they move too slowly for us to notice each movement affects other plates
When do you subduction zones occur
Scientist suggest that subduction zones form when convection current cools and sinks. The same process might be occurring in Earth’s mantle creating the force behind plate tectonics
Could the convection currents cause the Atlantic Ocean to widen
Convection currents might be causing the Alantic ocean to widen at the mid Atlantic Ridge
Who is a seismologist
Seismologist study earthquake by reading seismograph this report is printed out it’s called a richer scale
What is a seismograph
A seismograph is the special tools scientist use to measure earthquakes inside the seismograph has a pen when the bedrock moves a pen draws how big the earthquake is
What is a Richter scale
Describes the magnitude of an earthquake
Describe seismic waves
Energy Waves that travel out words from the source
What does aftershock mean
smaller earthquake that can cause buildings to collapse
Primary wave
Last for about one minute travel through the centre of the earth quake rattles dishes
Secondary wave
Lasts about 1 1/2 minutes slower than primary wave passes through glass
Surface waves
Last about six minutes for slowest of the three breaks apart roads and buildings
Why is it important to know that some waves go through liquids and others do not
If he can go through a liquid it can cause tsunami’s
Is it possible to determine the location between primary and secondary Waves?
It is possible to determine the location of an earthquake by the distance between primary and secondary Waves. The farther apart they are the farther away the earth. Quake is
What does focus mean
It’s where the earthquake begins
Is the epic centre
The epic centre is right above the focus