Deep beneath the Yellowstone Supervolcano lies a complex network of magma reservoirs that could be causing a shift in volcanic activity towards the northeast. Researchers from the US Geological Survey and Oregon State University have been examining the natural electromagnetic fields in the area and have discovered at least seven significant magma reservoirs at varying depths, between 4 to 47 kilometers, right at the boundary of the Earth’s crust and mantle. Some of these magma bodies are interconnected, creating a dynamic system that could influence volcanic behavior.
Interestingly, their findings indicate a potential decline in volcanic activity in the western regions of Yellowstone. Certain sections of the caldera host magma chambers that are characterized by low melt fractions, reducing their likelihood of erupting. Conversely, a prominent reservoir of rhyolitic magma—associated with explosive eruptions—has been identified beneath the northeastern part of the Yellowstone Caldera. This reservoir is being actively replenished with heat and materials from basalt migrating up from the Earth’s lower crust, leading to the accumulation of approximately 440 cubic kilometers of magma.
The research team suggests that the epicenter of future explosive rhyolitic eruptions may indeed be shifting towards the northeast Yellowstone Caldera, highlighting a greater probability of volcanic activity in this area. However, it’s crucial to understand that these observations do not suggest an eruption is on the horizon. Volcanic phenomena unfold over geological timescales, which are significantly longer than our human experience. Over the past 2.1 million years, Yellowstone has witnessed three cataclysmic eruptions, with an average recurrence interval of about 725,000 years. Since the last major eruption occurred around 631,000 years ago, it does not imply that another is due imminently.
Forecasting volcanic eruptions is notoriously challenging, so it’s wise to approach these findings with caution. The study detailing these insights has been published in the esteemed journal Nature.
