Where will the next Doomsday volcano erupt? Scientists have finally unveiled the mystery behind it.

Today, the Doomsday Volcano in Yellowstone is relatively calm, yet it is known that major caldera-forming eruptions have occurred here in the past: 2.8 million years ago, 1.3 million years ago, and 640,000 years ago. Since then, the volcano has remained in a state of relative tranquility, but scientists believe that it will inevitably erupt again, and now we know when that might happen, according to Live Science.

In a new study, researchers conducted a thorough analysis of the magma storage system in Yellowstone and discovered that, in the long term, liquid magma will likely accumulate in just one region. In simple terms, scientists have figured out where the supervolcano in Yellowstone is expected to erupt in the future.

The eruption of the Doomsday Volcano is not expected to happen anytime soon. Scientists believe that by that time, Yellowstone may no longer be a national park, as any eruption is anticipated to occur only after hundreds of thousands of years. Nevertheless, according to co-author of the study, volcanologist-seismologist Ninfa Bennington from the Hawaiian Volcano Observatory, future eruptions will most likely be concentrated on the northeastern side of the national park.

The results of the new study indicate that the molten magma beneath Yellowstone is not stored in a single large mass but is hidden in four separate reservoirs within the caldera's crust. In the west, the reservoirs do not contact deep mantle rocks that could heat them from below, keeping them liquid and eruptible. Meanwhile, in the northeast, near the landmark known as Sour Creek Dome, deep rocks heat the magma trapped in the crust. In simple terms, scientists believe that the magma on the western side of Yellowstone will likely cool and solidify, while the northeast will remain hot.

In previous studies, researchers used the passage of earthquake waves through the caldera to evaluate where liquid magma was located compared to solid rock beneath the park. The issue is that the waves can change their behavior for a variety of reasons, including the hardness of the material or its temperature. As a result, it is difficult to distinguish hot solid rock from similarly liquid magma.

In the new study, scientists employed a different method known as magnetotellurics. It is known that the Earth's rotating core creates a magnetic field surrounding the planet. Since magma contains magnetic minerals, pockets of underground liquid magma generate their own mini-magnetic fields, which can also be detected at the surface. Using instruments placed around Yellowstone, researchers mapped these mini-fields to locate hidden magma pockets.

The results of their analysis show that together, the four pockets contain more liquid magma than was present in Yellowstone's depths during past major caldera-forming eruptions. It is known that the bulk of the magma lies at depths of 9.6 to 11.2 kilometers beneath the surface. At the same time, scientists believe that only in the northeastern part of the caldera does magma come into contact with hot basaltic rock, which can keep it in a liquid state.

Despite the large volume of magma accumulated beneath Yellowstone, the caldera is unlikely to erupt anytime soon. The fact is that magma has accumulated in the pore spaces within the solid rock of the caldera, similar to water in a sponge. Only when more than 40% of these pore spaces are filled can the magma in the pores connect, become mobile, and begin to erupt. Meanwhile, scientists have found that the current filling of these pores is only 20% or less.