are you afraid of volcanos? A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape 
I wouldn't want to live near one! Correct! I've been following the recent lava flows from the volcano in the Island of Hawaii.
I have heard that a mid-oceanic ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates 
Interesting! Yes those tectonic plates are involved with volcanoes! Earthquakes too I believe!
speaking of hawaii  These so-called "hotspots", for example Hawaii, are postulated to arise from upwelling diapirs with magma from the core–mantle boundary