It seems that although the Pacific 'Ring of Fire' [NZ - Japan - Alaska - Mexico - Chile]is well known for significant and persistent eruptions, to get something really big if less frequent you need to step a little to one side and look at Indonesia [Krakatoa, Tambora, Lombok as in the article; also Toba a long way back]. A different quality of magma? Deeper interaction betwen plates?
Originally Posted by: DEW