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Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Mayank vedwal Vedwal
Here option C is correct. Because at 660 km depth Sillicate structure changes from 4 fold coordination to 6 fold coordination and olivine which is in gamma phase (ringwoodite) changes to pervoskite. Pervoskite is a type of structure shown by sillicate at this depth .