Don't be fooled by those tourist volcanoes that reliably produce small basaltic lava eruptions. A new study shows they hide the same chemically diverse magmas in their underground plumbing systems as volcanoes that generate explosive activity.
Some volcanoes in Iceland, Hawai'i and the Galápagos Islands consistently produce lava flows of molten basaltic rock which form long rivers of fire down their flanks. They are so slow, you can outwalk them, and therefore so predictable you can visit them but unless you build a house in front of one, they are safe.
Yet they share chemistry in common with Vesuvius or Mt. St. Helens, which means they are not as timid as we think.