Volcanic ‘scream’ precedes explosive eruptions
The study of tremors in the lead up to the 2009 eruption of Redoubt, a volcano in Alaska, appears in Journal of Volcanology and Geothermal Research.
Those quakes continuously rose in pitch like a volcanic glissando - a musical glide from one pitch to another.
Subterranean magma plumbing systems sit beneath volcanoes and feed pressurised molten rock toward the surface before eruptions.
As the magma flows through deep conduits and cracks, it generates small seismic tremors and earthquakes.