The short answer is that while lava is hot, it's not hot enough to melt the rocks that make up the side of the volcano.
It feels as if volcanoes in our region are going off at a high rate right now - but it's reasonably normal activity for the "Ring of Fire" belt running around the Asia Pacific.
Research suggests a new threat to life on Earth from the meteorite's crash: Via seismic waves, the impact triggered massive undersea eruptions, as big as any ever seen in our planet's history.
A new study has found a way to predict eruptions at Mount Etna within two weeks.
We asked three volcanologists what to look out for in the year ahead.
Robots, like drones, are filtering the natural world through algorithms and turning the world into data.
And will the aviation sector implement vital lessons learned from Icelandic disruption in 2010?
Stand by for drones, robots and sensors to the rescue.
Until late November, Bali's high economic dependence on tourism led its Tourism Board to dismiss the dangers of the Mount Agung volcano. This severely undermined the reputation of destination Bali..
'Volcano forensics' involves a mixture of modern day monitoring and analysis of past eruptions. Geologists use volcanic rocks as a kind of time capsule to assess what happened previously.
How do scientists predict volcanic eruptions? To do so with accuracy, they need to know the individual volcano and its history very well.
The world watches and waits to see what will happen next at Bali's Mt Agung, an active volcano.
Volcanologists study the formation and eruptions of volcanoes - surely one of the most interesting jobs around. However, it can also be very dangerous.
The saga of Öræfajökull suggests we should take small earthquakes in the region seriously.
Human-induced earthquakes have been reported from every continent except Antarctica. We asked a geologist to investigate whether North Korea's nuclear tests could trigger geological changes.
Satellite research in Ethiopia is opening up a new frontier in the hunt for geothermal power.
Hundreds of earthquakes a day are being recorded near Mount Agung in Bali as the volcano threatens to erupt for the first time in more than 50 years.
Volcanic ash can cause a nuisance to farmers, burying agricultural lands and damaging crops. But in the long term, this ash will create highly productive soil that can support huge populations.
They erupted for billions of years and make Earth's volcanoes look like molehills. Here's what we know and what we don't know about them.
Ambae does not fit the stereotypical image of a volcano, and it poses a significant threat.