Earth's Surface Composition

Earth's Surface Composition

• The Earth's surface has three primary compositional layers: Crust, Mantle, and Outer Core.

Lithosphere and Asthenosphere

• The Lithosphere is the outermost layer of the Earth, containing the entire Crust.
• The Asthenosphere is a layer of the Earth beneath the Lithosphere, characterized by high temperatures and pressure.

Inner Core and Outer Core

• The Inner Core is a solid layer of the Earth's composition, due to high pressure.
• The Outer Core is a liquid layer of the Earth, due to extremely high temperatures.

Plate Tectonics Theory

• The Plate Tectonics Theory states that the Earth's Lithosphere is divided into large moving plates.
• The plates move at an average rate of 15-20 inches per year.
• The process by which new land is formed through plate tectonics is the heated magma rising through cracks in the oceanic crust.

Key Characteristics of Plates

• The Earth's plates are described as moving in the Plate Tectonics Theory.
• New land is formed through volcanic eruptions, specifically by heated magma rising through cracks in the oceanic crust.