Foliated metamorphic rocks are characterized by which of the following?

• A. Randomly arranged minerals
• B. Alignment of minerals
• C. High porosity
• D. Low density

Answer: (B)

Foliated metamorphic rocks are distinguished primarily by the alignment of minerals within the rock. This characteristic results from the intense pressure and temperature conditions under which these rocks form, causing platy or flaky minerals, such as mica or garnet, to reorient perpendicularly to the direction of the applied stress. This alignment creates a layered or banded appearance, giving the rock its distinctive foliation.

In contrast, randomly arranged minerals would relate more to non-foliated metamorphic rocks, where the minerals do not exhibit any particular alignment. High porosity and low density are characteristics typically associated with sedimentary rocks rather than metamorphic rocks, as metamorphic processes tend to compact the minerals, decreasing porosity and often increasing density.