A new study by Chinese researchers suggests that the magma source of the Yellowstone supervolcano is shallower than previously thought, challenging long-held models of how supervolcanoes are fueled. According to the study, the Yellowstone volcano draws magma from a layer of 'magma mush' just below the Earth's crust, rather than from a vast chamber of liquid magma. The volcano sits atop a large, spread-out zone of partially molten rock known as a 'magma mush' system. Previously, scientists believed supervolcanoes were fueled by large magma chambers fed by narrow columns of superheated rock called magma plumes, but such chambers have been conspicuously absent from the biggest supervolcanoes, including Yellowstone.
According to the researchers, as tectonic forces stretch and tear the Earth's outer shell, molten rock seeps up from the upper edges of the semi-molten mantle to fill Yellowstone's magma chambers. If enough magma collects and pressure builds, these processes can lead to an eruption. The lava originates from a region just below the Earth's rigid outermost shell, the asthenosphere. As molten rock rises, it interacts with solid material to create a highly viscous magma mush. A layer of hot rock steadily flowing eastward beneath the caldera is tearing apart the stiff outer crust, creating a channel for magma to rise. This mechanism suggests that Yellowstone can fill its potentially explosive magma chambers more quickly than previously thought.
Supereruptions are 'one of Earth's most catastrophic geological hazards, having widespread environmental impacts, including climate disruption and mass extinction events.'
Supervolcanoes are extremely large volcanoes capable of launching over 1,000 cubic kilometers of rock, ash, and lava. The Chinese researchers described supereruptions as 'one of Earth's most catastrophic geological hazards, having widespread environmental impacts, including climate disruption and mass extinction events.' The Yellowstone supervolcano has produced two supereruptions over the past 2.1 million years. Experts have recently raised concerns that Yellowstone is more active than previously thought, though the new study's implications for eruption probability remain unclear.