Sakurajima is the Japanese supervolcano, found right next to the Kyushu city of Kagoshima. I would guess that it is the most active supervolcano in the world, as it regularly belches gas and ash. This week it starting belching more than that as these pictures testifies —http://www.theguardian.com/world/2016/feb/05/sakurajima-volcano-japan-erupts
Given recent research, this new activity is not necessarily an indication of a major eruption — for a cataclysmic eruption to occur, a major earthquake would be required to damage the ‘lid’ covering the supervolcano to a sufficient degree so as to release enough built up gas pressure to destroy said lid. However, this site has made the argument that such an eruption would indeed occur when the sixth seal is opened (Revelation 6:12-17).
There is scientific evidence that supports the notion that the melting of the land based ice in the Arctic and in Antarctica will trigger a new period of increased volcanic activity worldwide. There is no public index of global volcanic activity so we can only guesstimate if more of the world’s volcanoes are growing in their activity. However, if our arguments are correct, then Revelation is foretelling up to 3 possible separate catastrophic supervolcano eruptions — all of which will bring darkness to the world.
The recent belching of magma at Sakurajima is a reminder that the opening of the sixth seal will occur in the not so distant future. As the fifth seal has already been opened, it could actually occur any day now. The opening of the sixth seal will be plain to the whole world, and will be the final warning to Believers to prepare.