The region between two adjacent isograds ____.
A)does not vary in width within a given metamorphic formation
B)is always nonfoliated rock
C)is composed of non-metamorphosed rock
D)makes up a single metamorphic zone
E)is where rock types change

Question

Quizplus · Accepted Answer

Isograds are lines on a map that represent the first appearance of a particular metamorphic mineral under increasing grades of metamorphism. The region between two adjacent isograds, therefore, represents a range of metamorphic conditions and makes up a single metamorphic zone where specific minerals can form.

The Region Between Two Adjacent Isograds ____