GEO101 Personal question from the profesor

I’m working on a Geology question and need guidance to help me study.

Darby and others,

Basaltic magma is classified as mafic; it is considered by scientists to represent the average composition of oceanic crust. Continental crust, meanwhile, approximates the chemistry of granite, a felsic rock. What do the terms mafic and felsic mean, and where do those names actually come from?

More importantly, how did the two different chemical compositions of crust develop in the first place, billions of years ago? That question is a tough one. If you want to take a crack at it, here is an article: https://www.scientificamerican.com/article/the-evolution-of-continental-crust-2005-07/ (Links to an external site.) and here is a hint: Different minerals have different melting/freezing points. Olivine forms from magma at a very high temperature, while quartz forms from magma at a much lower temperature.