When two tectonic plates push together,pull apart or slide past one another, which of the following is most likely to occur?

• a delta
• a tidal wave
• an earthquake
• a typhoon

In the structure of soil, the A layer forms when clay and minerals washed into the B layer.  The A layer is also called ________.

• subsoil
• fertilizer
• topsoil
• humus

Soil with approximately equal parts of sand, clay, and silt is called_______.

• bedrock
• topsoil
• loam
• humus

The minerals present in the area will depend on ______

• parent rock
• climate
• altitude
• vegetation

What is soil?

• a mixture of rock and mineral paricles
• of decayed organic materials
• a mixture of air and water
• all of the above

Which processes are primarily responsible for the formation of soil?

• earthquakes
• meteorites
• weathering and decomposition 
• volcanic activity

In a soil profile, which horizon lies beneath the C horizon?

• bedrock
• subsoil
• topsoil
• clay

The decayed organic material in soil is called_______

• humus
• loam
• topsoil
• bedrock

Which layer of the Earth is solid iron and nickel?

• outer core
• inner core
• mantle
• crust

On average, about how fast are the tectonic plates moving?

• 1000 cm /year
• 10 meters/year
• 5 cm/year
• 5 meters /day