Untitled Flashcards Set

What are tectonic plates?

Slabs of rock or lithosphere floating on top of the mantle.

What is the mantle?

A molten sea of magma that tectonic plates float atop.

What are tectonic plates?

Slabs of rock or lithosphere floating on top of the mantle.

What is the mantle?

A molten sea of magma that tectonic plates float atop.

What causes the mantle to be liquid?

The heat given off by the Earth’s core.

What is the Earth's core composed of?

A dense ball of nickel, iron, and radioactive elements.

What happens at a divergent boundary?

Plates move away from each other, causing seafloor spreading.

What occurs at a convergent boundary?

Two plates collide, usually with the oceanic plate being subducted beneath the continental plate.

What is a transform boundary?

Where two plates slide past each other, often causing earthquakes.

What is soil?

A complex mixture of weathered rocks, living material, and organic material.

What are the three key factors in soil composition?

Minerals, open spaces, and organic materials.

What is the O horizon?

The top layer of soil filled with organic material.

What is the A horizon also known as?

Topsoil, containing both organic matter and minerals.

What distinguishes weathering from erosion?

Weathering is the breakdown of rocks; erosion is the movement of those rock pieces.

What forms igneous rocks?

Cooling of molten materials.

What are the three types of rocks?

Igneous, metamorphic, and sedimentary.

What is soil pH?

A measure of the acidity of soil.

How does acidic soil affect plant growth?

It has lower nutrient levels and can damage plant roots.

What are the major gases in Earth's atmosphere?

78% nitrogen, 21% oxygen, 1% argon, and 0.4% trace gases.

What is the troposphere?

The layer of the atmosphere closest to Earth where weather occurs.

What is the role of the stratosphere?

It absorbs UV radiation due to the dense concentration of ozone.

What occurs in the thermosphere?

It is the hottest layer and the region where the aurora borealis occurs.

What is a watershed?

An area of land that drains into a central body of water.

What characteristic separates different watersheds?

Slope, which determines the flow of water into different bodies.