Deep beneath Portugal’s São Jorge Island, a massive surge of magma silently pushed upward from more than 20 kilometers underground in 2022, triggering thousands of earthquakes and briefly raising fears of a volcanic eruption. Scientists discovered that the molten rock climbed astonishingly fast — enough to fill 32,000 Olympic swimming pools — before stalling just 1.6 kilometers below the surface in what researchers call a ‘failed eruption.’