Plate Boundaries
What are the three main types of plate boundaries?
Convergent, Divergent, and Transform
What type of geological landform formed by tectonic plate movements, can indicate past plate movement?
Trenches, mid-ocean ridges, mountain ranges, volcano, earthquake
What is radioactive dating?
The process used to determine the age of rocks and fossils by measuring the decay of radioactive isotopes.
Why did other scientist not support his theory?
He did not have enough evidence. The idea seemed strange (new). He did not explain how the plates moved.
What is Pangea?
A supercontinent that existed during the late Paleozoic and early Mesozoic eras.
What happens at divergent plate boundaries?
Tectonic plates move apart, causing new crust to form as magma rises to the surface.
How do fossils found in different continents support the theory of plate movement?
Similar fossils found on separate continents suggest they were once connected.
Different versions of an atom
What is an isotope?
What was the main idea of Wegener's theory of continental drift?
Continents were once joined together in a single landmass called Pangea and have since drifted apart.
What is the name of the section of Pangea that contains India, Antartica, Australia, South America, and Africa?
Gondawanaland
Causes Earthquakes
What are earthquakes?
What is the term for the remains or traces of ancient organisms found in rock layers?
A fossil
How does radioactive dating help scientists understand geologic time?
It provides a way to measure the age of rocks, which helps place events in Earth's history on the geologic time scale.
Name one piece of evidence Wegener used to support his theory.
Edges fit like puzzle pieces. Fossils of same species found on two different continents. Similar mountain ranges and rock types found on different continents.
The continents of Pangea fit together like?
One plate is destroyed, while the other plate is pushed towards plate. Mountain ranges and trenches are common
What is a convergent boundary?
What type of data can scientists analyze to support the theory of plate tectonics?
What is the distribution of fossils and rock layers?
Why does rock have to be formed by melting or cooling for radioactive dating to determine the rocks age?
These rocks do not start off with any Ar-40 atoms.
What was the name of the supercontinent Wegener theorized existed before the continents drifted apart?
Pangea
How did the breakup of Pangea affect Earth's climate?
It led to changes in ocean currents and climate patterns as the landmasses drifted apart.
What pattern do we see at ALL types of plate boundaries?
Earthquakes happening along plate boundaries.
Explain how sea-floor spreading supports the theory of plate tectonics.
New oceanic crust forms at mid-ocean ridges, pushing older crust away, showing that plates are moving apart.
The more Ar-40 atoms present means
The older the rock is
How did Wegener's ideas contribute to the modern understanding of plate tectonics?
What is the foundation for understanding continental drift and plate movements?
Discuss the significance of Pangea in understanding Earth's geological history.
Pangea helps explain the distribution of species and geological features, showing how plate tectonics has shaped Earth's surface over time.