Formation
They are created when magma reaches the surface but, as there is a large difference in temperature between the lava and the water, the surface of the emergent tongue cools very quickly, forming a skin. The tongue continues to lengthen and inflate with more lava, forming a lobe, until the pressure of the magma becomes sufficient to rupture the skin and start the formation of a new eruption point nearer the vent. This process produces a series of interconnecting lobate shapes that are pillow-like in cross-section. The skin cools a lot faster than the inside of the pillow, so it is very fine grained, with a glassy texture. The magma inside the pillow cools more slowly, so is slightly coarser grained than the skin, but still classified as fine grained.
Read more about this topic: Pillow Lava
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“The formation of an oppositional world view is necessary for feminist struggle. This means that the world we have most intimately known, the world in which we feel “safe” ... must be radically changed. Perhaps it is the knowledge that everyone must change, not just those we label enemies or oppressors, that has so far served to check our revolutionary impulses.”
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