This lava is flowing from what geologists call a hot spot that is located deep under the ocean surface beneath Earth's crust. Hot spots form above mantle plumes that reach a sweltering 2,500 ...

The lava has a thin crust on it that's caused by air cooling, so the geologist has to break this with his rock hammer before taking a sample. Lava sampling regularly happens at Kīlauea Volcano to ...

Some volcanoes, like Mauna Loa in Hawaii are caused by hot spots in the Earth’s crust. These do not erupt violently and lava usually flows slowly out of them.