Magma

Magma can rise when pieces of Earth's crust called tectonic plates slowly move away from each other. The magma rises up to fill in the space.

Magma from the mantle or lower crust rises through its crust towards the surface.

The screams are harmonic tremors, and researchers at the University of Washington believe they are caused when magma is forced through a narrow conduit at greater and greater pressure into the heart of the volcano.

North Kivu province Military Governor Constant Ndima Kongba announced the mandatory evacuation of 10 neighborhoods in the city after seismic and ground deformation data indicated the presence of magma under Goma, extending under adjacent Lake Kivu.

In a report, published in the magazine Nature, a group of scientists say that X-ray and spectroscopic analysis of a small diamond found in magma from a Brazilian volcano showed a 40 micrometer speck of a mineral called ringwoodite.

All volcanoes in the dataset with magma flow rates greater than one-tenth of a cubic kilometer per year—roughly 40,000 Olympic swimming pools—ruptured their magma chambers within a year.

By the pathside, there are occasional large boulders that shown black crystals the size of a fingernail; these are pyroxene minerals that had time to crystallise out deep within the chamber of liquid rock – or magma – beneath the volcano.