Summations Only

But that is not at all clear just from the picture when the flat layers were laid down. There's something odd about that picture. Where is it and what is it?

Do blieve that's a COAL SEAM , not igneous rock. Edited by Faith, : No reason given.Edited by Faith, : No reason given.

This question is a bit off the direct topic, but surely you are not limiting the geological column to igneous rock? Sedimentary rock includes rock made up of chemical substances (salts and other minerals), organic substances, and of course broken up bits of other rocks. I don't see any reason why combinations of sedimentary, igneous, and metamorphic rocks might not be present.But back to the topic. You believe you have a definition of the geological column that is at variance with the definition everyone else claims is correct. But you have yet to do the obvious thing in defense of your position, which would be to site a source using your definition. Why is that?Edited by NoNukes, : No reason given.

I didn't say it was. I said it was a geological column, which it is.There isn't really an actual real thing that is the geological column, because its going to be different at different places.What people refer to as the Geological Column is just an abstraction that represents all of the layers underground.And it can certainly contain volcanic layers, and layers that aren't completely flat.

Shit, an hour or so ago she said that the geological column is only made up of sedimentary rock, and that igneous rocks from volcanoes don't get deposited in the column.It really is just a big old confused mess, full of nonsense and falsehoods.

I'm trying to avoid the kind of editorializing that seems to be drawing off topic banners lately. But would it be too patronizing if I noted for Faith's benefit that coal is sedimentary rock?Okay. I'm butting out of the geology thread again. Describing the rock cycle in the terms used in 8th grade science texts is the extent of my knowledge.Edited by NoNukes, : No reason given.

WHAT? "...limiting the geological column to igneous rock." WHAT?Did you mean "sedimentary rock?" That would be closer. But I never said there is no igneous rock in the Geo Column, just that it doesn't form layers like the sedimentary rock. It forms sills, it forms dikes etc.

yes COAL is a sedimentary rock. I don't know how this conversation is getting so confused but that was the point. Igneous rock IS NOT sedimentary rock, what Coyote posted WAS sedimentary rock though he thought it was igneous rock. No, it was a coal seam, which IS sedimentary rock. Yikes this IS a mess but it is certainly not my fault that it is. You just didn't read carefully enough or get the whole context.

I see your point. Using coal as an example of igneous rock would be an improper example. Which leaves the question of where you get the idea that magma cannot form layers. Would the following be an example of a layer formed by igneous rock that would meet your standards?Layered intrusion - Wikipedia

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A layered intrusion is a large sill-like body of igneous rock which exhibits vertical layering or differences in composition and texture. These intrusions typically are many kilometres in area covering from around 100 km2 to over 50,000 km2 and several hundred metres to over a kilometre in thickness.[1] While most are Archean to Proterozoic in age (for example, the Paleoproterozoic Bushveld complex) they may be any age such as the Cenozoic Skaergaard intrusion of east Greenland.[1] Although most are ultramafic to mafic in composition, the Ilimaussaq complex of Greenland is an alkalic intrusion.

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How about thishttp://www.nature.nps.gov/.../Sites/DETO/HTML/ET_Igneous.htm

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Magma that cools at or near the Earth’s surface cools very quickly. Therefore, the crystals don’t have time to grow. The resulting rock is called an extrusive igneous rock or volcanic rock and contains crystals that are too small to see with the naked eye. This texture is called aphanitic and the most common aphanitic rock is called basalt. It forms much of the ocean floor.

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Is the ocean floor a layer that you would acknowledge as part of the geological column?It is true that the layers of the geological column are generally sedimentary layers. At least as best as I know. But the base layer is granite, which is not sedimentary. And of course, all rocks, except maybe granite, become sedimentary via erosion.dating | Definition, Geology, Methods, & Facts | Britannica.

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Most methods for determining relative geologic ages are well illustrated in sedimentary rocks. These rocks cover roughly 75 percent of the surface area of the continents, and unconsolidated sediments blanket most of the ocean floor. They provide evidence of former surface conditions and the life-forms that existed under those conditions. The sequence of a layered sedimentary series is easily defined because deposition always proceeds from the bottom to the top. This principle would seem self-evident, but its first enunciation more than 300 years ago by Nicolaus Steno represented an enormous advance in understanding. Known as the principle of superposition, it holds that in a series of sedimentary layers or superposed lava flows the oldest layer is at the bottom, and layers from there upward become progressively younger. On occasion, however, deformation may have caused the rocks of the crust to tilt, perhaps to the point of overturning them. Moreover, if erosion has blurred the record by removing substantial portions of the deformed sedimentary rock, it may not be at all clear which edge of a given layer is the original top and which is the original bottom.

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Sure, and a bowl of tomato soup might have a fly in it but it's still a bowl of tomato soup. Not sure, good question. Maybe I just can't believe it's not obvious. But I'll see what I can find to cite for support.Edited by Faith, : No reason given.

Lava and Rock layers on a road, Ascension Island, Atlantic | FlickrWhat you believe is wrong, as usual.

But it can, and it does.If lava flows over rocks on the surface and then later more sediment is deposited upon the cool and hardened lava flow, then that lava flow will form a layer in the geological column there.

Sure, but that's not a coal seam... its lava flow. Especially when they're responding to the 8th grade science as if they were a 5 year old.

The traps referred to in this image are layers of basalt originating from a series of volcanic eruptions which gave rise to the Deccan Traps in India which cover an area of 500,000 km2 and are 2000m deep. In between the two layers of igneous basalt in the picture is a 9m deep sedimentary layer of shallow marine origin.Edited by Malcolm, : Trying for a sensible size