What they found were four distinct magma reservoirs, sitting between 4 and 11 kilometers beneath the caldera. The reservoirs aren’t entirely liquid — they’re more like thick mushes of crystal and melt — but their existence reshapes how geologists assess eruption risks in the region. What a Yellowstone Super-Eruption Might Look LikeThere’s no suggestion that a catastrophic eruption is around the corner. The cooling could last 15–20 years, devastating global agriculture, shifting monsoon patterns, and causing mass ecological disruption. For now, tools like InSAR, multi-gas sensors, and magnetotelluric imaging give geologists their clearest view yet of what lies below.