Seismic Method: Graph
The x- and y-axes of the seismic method graph are.
What is: x = depth of Earth, y = speed of waves when travelling through Earth's interior
The composition of the Earth's crust is.
What is: Rocks
The theory of continental drift posits that the name of the supercontinent is...
The first person to introduce the theory of continental drift was...
What is: Alfred Wagner
On the graph, the P waves and S waves are.
What are: the two types of seismic waves used to study the Earth - one travels through both solids and liquids, and the other only through solids
The 4 compositional layers of the Earth are...
What is: crust, mantle, outer core, inner core
The 3 types of evidence used to support the theory of continental drift are...
What are: geological, paleoclimatic, paleontological
What observation about the coastlines of South America and Africa supports the idea of continental drift?
What is: they seem to fit like puzzle pieces
The 3 changes seen on the seismic methods graph are called.
What is: Moho discontinuity, Gutenberg discontinuity, Lehmann discontinuity
The 4 physical states of the layers of the Earth are...
What is: Lithosphere, Asthenosphere, Mesosphere, Endosphere
You find identical layers of ancient rock in both South America and Africa. What type of evidence do you classify this finding as?
What is: geological evidence
The Mesosaurus, an ancient freshwater reptile whose remains were found in both South America and Africa, is classified as what type of evidence supporting the theory of continental drift?
What is: paleontological evidence
Explain the Moho discontinuity and how it is shown on the graph.
What is: the Moho discontinuity marks the geographical boundary between the crust and mantle - shown in the graph as a change of speed and chemical composition in the S and P waves
What are the physical states of the Earth that make up the mantle are? What are the characteristics of each?
What is: Asthenosphere (upper mantle, ductile and viscous) and mesosphere (rest of the mantle, solid)
You discover glacial scratches on rocks in both present-dayy India and Antartica. What conclusion could you draw about the past positions of the continents?
What is: they were once connected (paleoclimatic evidence)
What process in the mantle below the crust helps to drive the movement of the tectonic plates?
What is: the convection circulation in the mantle
Explain the Gutenberg discontinuity and its effect on the S and P waves.
What is: the Gutenberg discontinuity marks the geographical boundary between the mantle and outer core - shown in the graph as a change of speed and chemical composition in the P waves and a stoppage of S waves
What is isostasy? How does it work?
Fossils of the same extinct fern, Glossopteris, are discovered on every southern continent. How would scientists use this discovery to support the theory of continental drift?
What is: that due to the plant being found on multiple continents, now far away from each other, in the past the landforms must have been connected.
Explain the process within the mantle that contributes to plate movement.
What is: heat from the core rises and softens the mantle rock - mantle rock rises upward - this pushes cooler rock downward - creates convection currents