30 points
>
>
Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
- IIT JAM
- Geology (GG)
Question below
2 Answer(s)
Answer Now
- 2 Likes
- 2 Comments
- 0 Shares
-
![comment-profile-img]()
>
-
![comment-profile-img]()
>
Sajan sarthak Best Answer
Phonolite contains least sillica ..In QAPF diagram phonolite is the only rock from these options going away from silica end or zero silicau can say ... Nephelline syenite is almost also having zero sillica but the more the away from the Q the less sillica will be. Rhyolite rich in silica. Syenite have volcanic equivalent trachyte is also having silica in good amount.
![cropped7771659876106129932.jpg]()
![cropped3275779595769336659.jpg]()
Do You Want Better RANK in Your Exam?
Start Your Preparations with Eduncle’s FREE Study Material
- Updated Syllabus, Paper Pattern & Full Exam Details
- Sample Theory of Most Important Topic
- Model Test Paper with Detailed Solutions
- Last 5 Years Question Papers & Answers
Sign Up to Download FREE Study Material Worth Rs. 500/-
Rahul kumar![best-answer]()
Answer: A and C; Less silica means silica undersaturated rocks. Phonolite (voocanic equivalent of nepheline) syenite have very low silica content and hence considered as silica undersaturated rocks. The percentage of silica in both nepheline syenite and phonolite are same but the difference is that phonolite is volcanic rock and nepheline syenite is plutonic rock.