Author Question: Identify the following igneous rocks based on their texture and mineral content. What will be an ... (Read 64 times)

Jipu 123

  • Hero Member
  • *****
  • Posts: 569
Identify the following igneous rocks based on their texture and mineral content.
 
  What will be an ideal response?

Question 2

What processes can form intermediate and felsic magmas from a melt that is originally mafic?
 
  What will be an ideal response?



Ptupou85

  • Sr. Member
  • ****
  • Posts: 334
Answer to Question 1

a. Fine-grained rock with 0 quartz, 0 potassium feldspar, 61 plagioclase feldspar, 13 biotite, 17 amphibole, 9 pyroxene, 0 olivine
b. Fine-grained rock with 0 quartz, 0 potassium feldspar, 67 calcium-rich plagioclase feldspar, 0 biotite, 0 amphibole, 25 pyroxene, 8 olivine
c. Coarse-grained rock with 0 quartz, 0 potassium feldspar, 52 calcium-rich plagioclase feldspar, 0 biotite, 0 amphibole, 32 pyroxene, 16 olivine
d. Coarse-grained rock with 0 quartz, 0 potassium feldspar, 0 plagioclase feldspar, 0 biotite, 0 muscovite, 0 amphibole, 56 pyroxene, 44 olivine
e. Fine-grained rock with 32 quartz, 26 potassium feldspar, 26 sodium-rich plagioclase feldspar, 5 biotite, 11 amphibole, 0 pyroxene, 0 olivine
By reference to text Figure 4.3: Andesite, Basalt, Gabbro, Peridotite, Rhyolite

Answer to Question 2

Fractional crystallization: Removal of early-formed, relatively low-silica minerals leaves a melt that is more silica-rich.
Magma assimilation: Mafic magma may melt more silica-rich surrounding rock; the resulting silica-rich melt blends with the originally mafic magma to produce an intermediate or felsic magma.
Magma mixing: A mafic magma may mix with a felsic magma to produce an intermediate magma.



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
 

Did you know?

More than 50% of American adults have oral herpes, which is commonly known as "cold sores" or "fever blisters." The herpes virus can be active on the skin surface without showing any signs or causing any symptoms.

Did you know?

To prove that stomach ulcers were caused by bacteria and not by stress, a researcher consumed an entire laboratory beaker full of bacterial culture. After this, he did indeed develop stomach ulcers, and won the Nobel Prize for his discovery.

Did you know?

The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.

Did you know?

A recent study has found that following a diet rich in berries may slow down the aging process of the brain. This diet apparently helps to keep dopamine levels much higher than are seen in normal individuals who do not eat berries as a regular part of their diet as they enter their later years.

Did you know?

Immunoglobulin injections may give short-term protection against, or reduce severity of certain diseases. They help people who have an inherited problem making their own antibodies, or those who are having certain types of cancer treatments.

For a complete list of videos, visit our video library