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→You Just Gotta Be Kidding Me
: I don't reject all mainstream evidence. Creationists simply have a different ''explanation'' for the evidence than evolutionists have. It's all the same evidence.
: I don't reject all mainstream evidence. Creationists simply have a different ''explanation'' for the evidence than evolutionists have. It's all the same evidence.
: [[User:Philip J. Rayment|Philip J. Rayment]] 21:09, 18 January 2008 (EST)
: [[User:Philip J. Rayment|Philip J. Rayment]] 21:09, 18 January 2008 (EST)
::I'm afraid that vulcanology doesn't work that way. The problem we're dealing with here is one that it is very hard for people to grasp - the sheer scale of geological time. Humans, by the scale of our paltry lifetimes, tend to think that 10 years or 50 years or 100 years are quite long periods of time. Volcanoes - and the world that powers them - tend to think in terms of thousands of years. There is no potential scenario that I can think of that can take into account the seamount-island chain in terms of YEC thinking. The powerhouse for a volcano is its magma chamber. The bigger it is, the larger the eruption, or at least the larger the potential eruption. To erupt the amount of material that makes up the Pacific seamount-atoll-island chain is vast. That either requires a vast magma chamber - bigger than anything that has ever been discovered so far, or a long-period series of eruptions. Let's look at the large magma chamber option. The problem here is that once a magma chamber empties due to a huge eruption, it then leaves a hole, into which the surrounding rock collapses, forming a void, or to give it it's right name, a caldera. The largest of these have been named supervolcanoes, and there are three of these in the US - Yellowstone, Long Valley and Valdez.
::But the Pacific hotspot has left a series of islands, not caldera, so this points to a more gradual series of building events, not a catastrophic series of limited eruptions. The creation of an island like Hawaii - the ones that preceded it - is not easy. Underwater volcanoes exist under conditions of extreme pressure. Don't forget that Hawaii is bigger than Everest. That's a huge amount of material, and requires thousands of years of eruptions - and that's just at the end of the current chain. There are hundreds of other volcanic edifices in Hawaii's wake, making the path of the hotspot. For each one to reach the surface requires again a huge amount of material. And even then, reaching the surface is just the start of the battle to build an island. When a vent approaches the surface of the sea then it can start oparting under conditions of low water pressure - and thus blowing material to the surface. Magma tends to fragment at this point as it cools, forming ashes or scoiria - small fragments. Unfortunately this stuff can be washed away by the sea very easily - look up what happened to the early versions of the isle of Surtsey off Iceland, or a seamount that broached the surface off the coast of Sicily in 1831, and which was promptly claimed by the UK, France, Italy, and Spain, before it was eroded back under the sea in 1832 when the eruption stopped. You need lots of liquid lava to cement everything in place, and again this takes time. Hawaii has made it, obviously. Again, this took time.
::As for your comment about sedimentary layers, I'm afraid that claiming that the 1980 Mount St Helens eruption blows the length of time out of the water is a bit premature. Every eruption of a volcano results in the venting of ash - which is finely pulverised magma. Every eruption is from magma that tends to be slightly different from the last. We can tell this by the chemical composition of the ash. Examining the layers around Mount St Helens show lots and lots of layers - but all are from the same magma source, created at the same time, and with the same chemical signature. Worse still, these layers tend to be from events like pyroclastic flows, which are very common to volcanoes. Pompeii and Herculaneum were hit by these things, with the latter also being hit by lahars, or hot mud flows. Again, these can occur again and again in one eruption event.
::By the way I have a question - why is it that the northern and southern hemispheres are scarred by valleys that were scarred by glaciers and not water?
::Another short post! You're right, these things can just suck you in. [[User:Darkmind1970|Darkmind1970]] 18:31, 21 January 2008 (EST)