Erupting volcanoes are forming new real estate all around our planet. Beneath Iceland and Hawaii, hot lava upwelling from deep underground is hardening into rock. Hotspots create chains of volcanoes on these islands as a tectonic plate slowly crosses a mantle plume. In Iceland, there are also volcanic eruptions occurring from the location astride the spreading center known as the Mid-Atlantic Ridge. The result: LOTS of lava.