Seashells on tops of mountains.

I'm not really understanding it either, and I have a geology degree.Back in message 4 you say: Are you saying the would be at the same elevations because the same type critters would be at the same depth? You know, shallow water life forms vs. deep water life forms.Moose

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Professor, geology, Whatsamatta U
Evolution - Changes in the environment, caused by the interactions of the components of the environment. "Do not meddle in the affairs of cats, for they are subtle and will piss on your computer." - Bruce Graham

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"The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness." - John Kenneth Galbraith

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"Nixon was a professional politician, and I despised everything he stood for ” but if he were running for president this year against the evil Bush-Cheney gang, I would happily vote for him." - Hunter S. Thompson

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"I know a little about a lot of things, and a lot about a few things, but I'm highly ignorant about everything." - Moose

Various tectonic processes cause the uplift of mountains. Earthquakes may well be a byproduct, but are not really the cause. The uplifted material may or may not have an above sea level origin. Certainly, if the materials are marine origin sediments, then the origins are from below sea level. Actually, the limestone sediment was formed in the marine environment, largely biogeneticly. In other words, the limestone (calcium carbonate) of the rock itself is produced by organisms. Although there may well be related subduction activity, tectonic uplift is not subduction.Or something like that. Further comment from our staff of geotypes is welcome.Moose

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Professor, geology, Whatsamatta U
Evolution - Changes in the environment, caused by the interactions of the components of the environment. "Do not meddle in the affairs of cats, for they are subtle and will piss on your computer." - Bruce Graham

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"The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness." - John Kenneth Galbraith

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"As democracy is perfected, the office of president represents, more and more closely, the inner soul of the people. On some great and glorious day the plain folks of the land will reach their heart's desire at last and the White House will be adorned by a downright moron." - H.L. Mencken (1880-1956)

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"Nixon was a professional politician, and I despised everything he stood for ” but if he were running for president this year against the evil Bush-Cheney gang, I would happily vote for him." - Hunter S. Thompson

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"I know a little about a lot of things, and a lot about a few things, but I'm highly ignorant about everything." - Moose

Sorry about not giving more information in my previous message. I wasn't really up to posting much, but I felt I couldn't let your less than accurate information just pass.I do have a geology degree, but it and the course including mountain building was 30 years ago. I wasn't that strong on it back then, and I've forgotten much since then.Orogeny - Wikipedia

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Physiography

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The process of orogeny can take tens of millions of years and build mountains from plains or even the ocean floor. Orogeny can occur due to continental collision or volcanic activity. Frequently, rock formations that undergo orogeny are severely deformed and undergo metamorphism. During orogeny, deeply buried rocks may be pushed to the surface. Sea bottom and near shore material may cover some or all of the orogenic area. If the orogeny is due to two continents colliding, the resulting mountains can be very high (see Himalaya).

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Orogeny usually produces long linear structures, known as orogenic belts. Generally, orogenic belts consist of long parallel strips of rock exhibiting similar characteristics along the length of the belt. Orogenic belts are associated with subduction zones, which consume crust, produce volcanoes, and build island arcs. These island arcs may be added to a continent during an orogenic event.

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I'm not real happy with the above quoted information, but I don't offhand have anything better to offer.Perhaps the best case study is the Appalachian orogeny, of which the Alleghenian orogeny is apparently synonymous and/or the most significant event. Other earlier Appalachian region orogenies are the Taconic orogeny and the Acadian orogeny. In short, orogeny is caused by continental collision. It would seem that this would require the subduction of oceanic crust prior to the collision. This subduction event probably would be considered part of the orogenic event.In all, study of an orogenic event can be complex. But the above cited material can hopefully function as a starting point for further discussion.Please, no POTM nominations for this dog of a posting. Moose

References for the subduction zone related origin of the Deccan volcanics, please.Per here, they are:

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It is postulated that the Deccan Traps eruption was associated with a deep mantle plume. The area of long-term eruption (the hotspot), known as the Runion hotspot, is suspected of both causing the Deccan Traps eruption and opening the rift that once separated the Seychelles plateau from India. Seafloor spreading at the boundary between the Indian and African Plates subsequently pushed India north over the plume, which now lies under Runion island in the Indian Ocean, southwest of India. The mantle plume model has, however, been challenged.

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The Deccan Traps are of basaltic composition, for which the deep mantle plume hypothesis would seem to make sense. Not subduction zone related volcanism, but independent of needing any plate collision (although they did happen at the same time).Moose