A GIANT supervolcano hidden beneath California could be an equal if not greater threat to the US than Yellowstone volcano, scientists have revealed. The 20-mile long Long Valley Caldera in eastern ...

The city of Mammoth Lakes sits on the edge of the Long Valley Caldera formed around 700,000 years ago. This caldera is 15 miles in diameter and is North America's second largest. 1. The Long Valley ...

It’s been around 100,000 years since California’s Long Valley supervolcano experienced a major eruption, but this supposedly dormant caldera has been acting a bit strangely over the past four decades.

A spring surge of meltwater, seeping through vertically tilted layers of rock, caused a seismic swarm near California's Long Valley Caldera in 2017, according to new research. A spring surge of ...

A long-dormant supervolcano in California still holds over 1000 cubic kilometres of semi-molten magma. The find suggests the supervolcano is not entirely extinct, but a major eruption remains ...

05:07, Sun, Aug 12, 2018 Updated: 09:19, Sun, Aug 12, 2018 The amount of magma in the Long Valley Caldera is so large it could support an eruption equivalent to the massive one which occurred 767,000 ...