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).
Convergent boundaries that involve at least one oceanic plate form subduct â¦ ion zones, where an oceanic plate plunges into the mantle. Volatiles carried into the mantle lower the melting point of the rock there, allowing magma to form. At divergent boundaries the crust becomes thinner. This reduces pressure on the upper mantle, thus lowering melting points and generating magma. Transform boundaries have no such means of producing magma.