What volcanic events formed Crater Lake, Oregon? When did they take place?
A) A powerful explosion blew away the top of a stratovolcano 10 million years ago.
B) Caldera collapse followed major ash and pyroclastic-flow eruptions 6000 years ago.
C) The crater of a large, extinct cinder cone filled with water 5 million years ago.
D) Landslides and volcanic mudflows dammed the Mazama River 500 years ago.
B
You might also like to view...
If an alcoholic beverage is 20% alcohol by volume, what is its proof?
A. Proof is a measure of the age of a fermented beverage. B. 20 proof C. 10 proof D. Proof is a measure of flammability. E. 40 proof
What is the central thesis of the theory of organic evolution?
The bending of light as it passes around objects is referred to as ____
A) dispersion B) diffraction C) refraction D) reflection
Movement of affluent residents to suburbs usually begins the process of exurb migration and urban blight
Indicate whether the statement is true or false