The difference between tephra and tuff is that ____________.
A) tephra is created in ash falls, whereas tuff is created in pyroclastic flows
B) tephra hasn't become a rock, whereas tuff has
C) tephra is always silicic, whereas tuff is always basaltic
D) All of the above are correct.

Question

Quizplus · Accepted Answer

Tephra and tuff both refer to volcanic ash, but tephra refers to loose, unconsolidated ash while tuff has become compacted and cemented together to form a rock. Option A is incorrect because tephra can also be created in pyroclastic flows. Option C is incorrect because neither tephra nor tuff are limited to a specific composition. Option D is incorrect because only option B is correct.

The Difference Between Tephra and Tuff Is That ____________