Continental Drift and Plate Tectonics

What is the process called through which tectonic plates interact and move?

Which of the following supercontinents existed over a billion years ago?

At what rate are the North American and Eurasian tectonic plates moving away from each other?

What geological feature is formed by the process of seafloor spreading?

What was one major flaw in Wegener's theory of continental drift?

What will happen to the African continent along the Great Rift Valley system?

What substance aids in the process of seafloor spreading by rising from within the Earth?

What is a significant characteristic of the tectonic plates?

Who is most associated with the theory of continental drift?

What was the name of the supercontinent that Wegener proposed existed?

Which fossil evidence did Wegener use to support his theory of continental drift?

What type of climate evidence did Wegener find in Svalbard, Norway?

How did Wegener demonstrate the geological relationship between continents?

What did Wegener believe about the movement of continents?

Approximately how many million years ago did Pangaea begin to break up?

What was Wegener's profession before he proposed the theory of continental drift?

Continental Drift and Plate Tectonics

Continental drift was an early theory explaining how continents moved, largely associated with Alfred Wegener.
Wegener proposed that all continents were once part of a singular landmass known as Pangaea.
He published his theory in the early 20th century based on evidence from biology, botany, and geology.

Evidence for Pangaea

Fossils of the mesosaurus, a freshwater reptile, are found exclusively in southern Africa and South America, indicating a shared habitat.
Plant fossils discovered in Svalbard, Norway, are of tropical species, suggesting it had a warm climate in the past.
The fit of the east coast of South America with the west coast of Africa resembles a jigsaw puzzle, showing geological similarities.
Appalachian Mountains in the eastern USA share geological traits with the Caledonian Mountains in Scotland.

Timeline of Pangaea

Pangaea existed approximately 240 million years ago and started breaking apart around 200 million years ago.
Several supercontinents have formed and fragmented during Earth's history, including Pannotia (600 million years ago) and Rodinia (over 1 billion years ago).

Tectonic Activity

Wegener's theory lacked a mechanism to explain continental movement, leading to skepticism among scientists.
Current understanding attributes continental movement to tectonic plates, massive rock slabs that constantly shift and interact.

Seafloor Spreading and Rift Valleys

Seafloor spreading occurs at mid-ocean ridges, where molten rock adds new oceanic crust, pushing continents apart.
The North American and Eurasian plates are drifting apart at about 2.5 centimeters (1 inch) per year due to the Mid-Atlantic Ridge.
Rift valleys form when a landmass is splitting apart, such as the East African Rift, which will eventually separate Africa into two continents.

Explore the foundational ideas of continental drift and how they have evolved into the modern science of plate tectonics. Delve into Alfred Wegener's contributions and the historical context of these geological theories. This quiz will challenge your understanding of continental movements over time.