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Post by Celine 5E on Nov 17, 2014 13:44:36 GMT
The Type of Lava
The type of Lava coming out of a volcano depends on its mineral conten. Some Lava is very thin, and can flow out of a volcano in great rivers that go for dozens of Kilometers. Other Lava is very thick, and only flows for a short distance before cooling and hardening. And some Lava is so thick that it barely flows at all, and can plug up the plumbing of a volcano. The main types of Lava have been given Hawaiian names, because of the volcanic nature of the Hawaiian Islands: A'a: this is a basaltic Lava that doesnt flow very quickly.It Looks like a slowly moving mass of hot jello. Pahoehoe: this type of Lava is much thinner and less viscous than A'a. It can flow down the slopes of a volcano in vast rivers. The surface of the Lava congeals into a thin crust that Looks very smooth. Pillow Lava: is typically found erupting from underwater volcano vents. As soon as the Lava contracts the water, it's cooled down and forms a hardened Shell.
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