A scientist identifies a rock sample as basalt. Why did he do so?
A) He observed that the rock has a lot of silica, making it mafic.
B) He observed that the rock has a lot of silica, making it ultra-mafic.
C) He observed that the sample has little silica, making it felsic.
D) He observed that the sample has little silica, making it mafic.

Question

Quizplus · Accepted Answer

Basalt is a mafic rock, meaning it has relatively low silica content. Therefore, the scientist likely identified the rock as basalt after observing that it has little silica, making it mafic.

A Scientist Identifies a Rock Sample as Basalt