How are volcanos formed?
What is hot molten rock, ash and gases that escape from an opening in the Earth's surface?
A period of extremely cold temperatures when part of the planet's surface was covered with massive ice sheets.
What is an ice age?
The color of a mineral's powder
What is streak?
Japan is an example of an island ____
What is arc?
Linear, narrow, steep-sided, V-shaped depressions in the sea floor
What is ocean trenches?
A volcano that is erupting or has shown signs that it may erupt in the near future...
What is an active volcano?
Small pieces of rock, soil, and other materials
What is sediments?
What is continental crust made of?
What is granite (different granites)?
A boundary between two colliding plates, often associated with mountain building ocean trenches and volcanic islands
What is a convergent boundary?
An underwater chain of mountains
What is a midocean ridge?
The opening through which molten rock and gas leave a volcano
What is a vent?
This is the most destructive mass movement, happens when rock and soil slide quickly down a steep slope
What is a landslide?
What types of rocks make up the crust?
What is igneous, metamorphic, and sedimentary rocks?
Where two plates are moving apart, magma comes up to create new crust...
What is a divergent boundary?
What percent of the earth is covered by the ocean?
What is 71%?
An area where material from deep within Earth's mantle rises to the crust and melts to form magma.
What is a Hot Spot?
______ _____ occurs when gravity causes rocks, soil, and other pieces of sediment to move downhill
What is mass movement?
The layer of Earth between the crust and the outer core... this layer of solid and partly melted rock
What is mantle?
At a convergent convergent boundary where an ocean meets a continent, the ocean dives under.
What is subduction?
This creates midocean ridges, earthquakes, and volcanic activity.
What is sea floor spreading?
A bowl-shaped area that may form at the top of a volcano around the central vent.
What is a crater?
What are 5 ways erosion take place
What is Wind, Waves, water, Glaciers, Gravity?
The process by which sedimentary rock is formed in which sediments are squeezed together
What is compaction?
This place is in Africa and the plates are coming apart
What is the Great African Rift?
Dark colored, basaltic composition, avg density 3.0 gm/cc; avg thickness 6 km
What is oceanic crust?