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).
Best Answer: Because most volcanoes form through the process of convergent boundary plate subduction. As one plate is subducted beneath the other, overriding plate, it will reach a point in the mantle at which it will completely melt and form new magma.