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Why do mafic magmas tend to reach the surface much more often than silicic magmas?
- K. Crummell
A good question! There are a couple reasons: mafic magma starts hotter so it has a better chance of making it the whole way to the surface. For the second you need to go to the atomic level: the simple silicate structures allow mafic magmas to flow and move through the crust easier. Felsic minerals have generally more complex mineral structures (double silicate chains, rings, and sheets) and are stickier (imagine a log jam in a river and you've got the general idea).
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