greenspun.com : LUSENET : Introductory Geology, Oswego State : One Thread

In class today (2/16/01) we discussed how liquid lava sometimes comes out of holes underneath molten rock that has ulready hardened due to being on the cool surface. This question refers to one of the pictures that Dr. Gabel showed in class. After the liqiud lava flows from under the hardened lava is that space hollow or does it collapse under the rocks weight? Or do minerals start to grow in between?

-- Laura M Smith (LilRed1525@aol.com), February 16, 2001


I think that once the magma flow ceases, the rock chamber the magma comes out of it still filled with magma and it crystallizes to fill it in. The magma flows out beause the chamber doesn't have enough capacity to hold it, but once the flow ceases, the magma stops flowing out and just fills the chamber to capacity.

-- Christine Stenglein (carobchips@hotmail.com), February 18, 2001.

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