Author Question: Which minerals are the first to crystallize in a cooling magmaminerals with a lower percentage of ... (Read 25 times)

karlynnae

  • Hero Member
  • *****
  • Posts: 599
Which minerals are the first to crystallize in a cooling magmaminerals with a lower percentage of silica or minerals with a higher percentage of silica?
 
  What will be an ideal response?

Question 2

How does silica content effect volcanic eruptions?
 
  What will be an ideal response?



joneynes

  • Sr. Member
  • ****
  • Posts: 376
Answer to Question 1

Answer: Minerals with a lower percentage of silica.

Answer to Question 2

Answer: Silica content greatly effects magma viscosity. The greater the silica content, the greater the viscosity (resistance to flow). Magmas with a high silica content flow slowly, while magmas with a low silica content tend to flow more easily. As such, basaltic eruptions (low silica content) are very fluid while andesitic eruptions (high silica content) flow slowly. The high resistance to flow can act as a trap to gases in the magma that, as pressure builds up, can cause the volcano to erupt explosively.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).

Did you know?

Signs and symptoms of a drug overdose include losing consciousness, fever or sweating, breathing problems, abnormal pulse, and changes in skin color.

Did you know?

Once thought to have neurofibromatosis, Joseph Merrick (also known as "the elephant man") is now, in retrospect, thought by clinical experts to have had Proteus syndrome. This endocrine disease causes continued and abnormal growth of the bones, muscles, skin, and so on and can become completely debilitating with severe deformities occurring anywhere on the body.

Did you know?

Warfarin was developed as a consequence of the study of a strange bleeding disorder that suddenly occurred in cattle on the northern prairies of the United States in the early 1900s.

Did you know?

Fewer than 10% of babies are born on their exact due dates, 50% are born within 1 week of the due date, and 90% are born within 2 weeks of the date.

For a complete list of videos, visit our video library