Planet Earth and Plate Tectonics

15 Questions

What is the composition of the continental crust?

Mostly composed of granite

What causes the movement of tectonic plates?

Convection currents in the mantle

What is the lithosphere composed of?

Rocky crust and thin solid portion of the mantle

What lies at the center of the Earth?

Extremely hot and dense core

What are tectonic plates?

Huge slabs formed by broken lithosphere

What is the range of sizes for the major tectonic plates?

58.9 to 103.3 million kilometers squared

Which tectonic plate is responsible for creating the Himalayas?

Eurasian Plate

What does the Pacific Plate's collision with surrounding plates create?

'The Ring of Fire' and Mariana Trench

Where does the boundary of the African Plate extend into?

Atlantic and Indian Oceans

What was a key piece in explaining tectonic plates and their movement?

Discovery of Mid-Atlantic Ridge in the 1950s

What is the 'Roof of the World' believed to be a result of?

Collision of Indo-Australian plate with Eurasian plate

What evidence supports the theory that tectonic plates move and change their locations?

Fossil evidence found in Antarctica

Which plate is not listed as one of the minor tectonic plates?

Antarctic Plate

Where is the Cocos Plate located?

West coast South America

Which plate holds part of South Asia and is one of the minor tectonic plates?

Indian Plate

Study Notes

Theory of Plate Tectonics: based on data such as earthquake and volcano locations, rock and fossil ages
7 major tectonic plates identified: Pacific, North American, Eurasian, African, Antarctic, Indo-Australian, South American
Each plate named after what lies above it (e.g., North America on North American Plate)
8 minor plates exist, much smaller in size
Major plates range in size from 58.9 to 103.3 million kilometers squared
Thickness of tectonic plates: 15 km to 200 km, thinnest new oceanic crust, thickest mountainous continental crust
Pacific Plate: largest, covers Pacific Ocean, collides with surrounding plates, creates 'The Ring of Fire' and Mariana Trench
North American Plate: beneath North America, Greenland, and part of Iceland, geologically active, created Mid-Atlantic Ridge and Andes Mountains
Eurasian Plate: third largest, holds Europe and Asia, created Himalayas, boundary lies across Mid-Atlantic Ridge from North American Plate
African Plate: fourth largest, encompasses Africa, boundary extends into Atlantic and Indian Oceans
Mid-Atlantic Ridge: mostly underwater mountain range, creates new crust, forms boundary between many major tectonic plates
Discovery of Mid-Atlantic Ridge in the 1950s was a key piece in explaining tectonic plates and their movement.