Earth Science Flashcards

Which layer of Earth is composed primarily of iron and nickel and is responsible for generating Earth's magnetic field?

Answer: Outer core

Earth's outer core is a liquid layer of iron and nickel whose movement generates the planet's magnetic field through convection currents.

What type of rock is formed when molten magma cools and solidifies?

Answer: Igneous

Igneous rock forms directly from the cooling and solidification of magma or lava, making it the primary rock type formed from molten material.

The theory of plate tectonics explains that Earth's lithosphere is divided into large sections called:

Answer: Tectonic plates

The lithosphere is divided into tectonic plates that float on the semi-fluid asthenosphere and move relative to one another, driving geologic activity.

Which type of boundary occurs when two tectonic plates move away from each other?

Answer: Divergent boundary

A divergent boundary is where two plates separate from each other, allowing magma to rise and form new crust, as seen at the Mid-Atlantic Ridge.

What is the primary cause of the seasons on Earth?

Answer: Earth's axial tilt of 23.5°

Earth's axial tilt of 23.5° causes different hemispheres to receive varying amounts of direct sunlight throughout the year, creating seasonal changes.

Which process in the water cycle involves liquid water changing into water vapor?

Answer: Evaporation

Evaporation is the process by which liquid water absorbs heat energy and converts to water vapor, transferring water from Earth's surface to the atmosphere.

The Richter scale is used to measure which characteristic of an earthquake?

Answer: Magnitude (energy released)

The Richter scale quantifies the magnitude of an earthquake, which reflects the amount of seismic energy released at the earthquake's source.