Begin Slideshow. 1  If you've got a Trader Joe's in your neighborhood, chances are it's your go-to supermarket. It's cheap, convenient, and the snacks are unbeatable. 2  When I sent out an office poll about people's favorite items, I quickly found I wasn't the only one who can't get enough of what that grocery store offers.
Addendum: Differentiation of magma (fractional crystallization) also plays a big role in creating felsic magmas from mafic magmas. Also, granite can form at convergent boundaries that involve continental crust only (e.g., Indian and Asian plates).
Volcanoes occur at divergent plate boundaries because of the new crust formed by solidifying of magma on the ocean bed which is very weak so the heat and pressure from the magma chamber will become too high to handle and there will be an eruption. Volcanoes form where the earth's crust is thin an the magma can flow to the surface easier.