A giant wave caused by an earthquake under the ocean.
What is a tsunami?
100
This type of rock forms when lava from a volcano hardens.
What is an igneous rock?
100
Scientists have discovered that the mountains on the east coast of South America closely match the mountains on the west coast of Africa. How can two landforms that are so far apart be related?
What is continental drift?
200
volcano
What is an opening in Earth's crust out of which magma flows?
200
A unit of time measured in millions of years.
What is era?
200
Causes chemical weathering
What is acid rain?
200
A solid geometric shape formed by a mineral
What is a crystal?
200
Volcanoes are most likely to erupt on Earth here.
What is along the the plate boundaries?
300
landform
What is a physical feature on Earth's surface?
300
The way a mineral reflects light.
What is luster?
300
Trenches, rift valleys, and abyssal plains
What are features of the ocean floor?
300
Subsoil has less what than topsoil?
What is humus?
300
These are returned to soil during crop rotation
What are nutrients?
400
erosion
What is the movement of pieces of weathered rock from one place to another?
400
Rocks change from one type to another over time in a process called:
What is the rock cycle?
400
Small streams that start in the mountains and join larger streams.
What are tributaries?
400
This type of rock forms when bits of dirt, dust, sand, and soils are pressed together
What is sedimentary rock?
400
The soil horizon is divided into three layers. This layer contains humus.
What is the A horizon?
500
fault
What is a crack in the Earth's crust?
500
wind, moving water, and solar energy are all
What are alternative energy sources?
500
Someone who studies Earth's structure and history.
What is a geologist?
500
These are formed from parts of decayed ocean plants and animals buried in the ocean floor.