Unit 2: Dynamic Earth Flashcards
Who noticed that the continents look like they fit together like a puzzle?
Alfred Wegener
What evidence is there to support continental drift?
- Continental coastlines fit together.
- Similar fossils found on different continents.
- Similar geological features found on different continents.
- Similar ancient climates found on different continents.
How many millions ago do scientist believe the continents were combined into Pangaea?
200 Million Years Ago
What are three ways the oceanic crust differs from the continental crust?
- They are thinner.
- They are younger.
- They are denser.
What happens when when tectonic plates interact?
Volcanos are formed and earthquakes happen
What causes the tectonic plates to move?
Earth’s internal heat (aka convection).
What are the key features of divergent boundaries?
- Plates move away from each other.
- They form mid-ocean ridges and rift valleys.
When oceanic plates collide, what happens?
The plate sinks (subducts) beneath the continental plate creating volcanoes.
What happens at transform boundaries?
The plates slide past each other.
When is created when a tectonic plate moves over a hotspot?
A chain of volcanoes is formed.
Where do hotspots form?
In the middle of the tectonic plate NOT where they collide.
Who mapped the seafloor and proposed subduction?
Hess
Who found a pattern in paleomagnetism to support seafloor spreading?
Vine and Matthews
Who found evidence that plates move during earthquakes?
Plafker
Who discovered hotspots and transform faults?
Wilson
