61 There are different sources of volcanoes. 63 There is a swelling of the floor before an eruption. 64 The crystallization begins inside the Earth. 65 There are different compositions of magma crystallizing in different rocks. 66 The magma is also composed of dissolved gases.

Growth and movements of bubbles drives eruptions. Different scenarios are possible, notably depending on bubbles mobility compared to the melt. They can rise faster through a permeable foam, inducing a passive degassing or be trapped because of a high viscosity and rise at the same velocity as the melt. 68 Passive degassing is linked t.

Unsteady magmatic flow, viscosity, feeding system. What happens in deep Earth? How to create magmas. Feeding system and changes in viscosity. More about the Big Idea. Because of that, understanding how magma flows, what parameters contro.

Volcanoes are exceptional in the fact that they grow. Each time they erupt lavas or tephras. By understanding collapses, we can understand more about.

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