Hello,
Uniformitarianism and catastrophism are 2 ways to look at Earth's geologic history.
Uniformitarianism suggests for example that surface features we see on Earth are caused by long term uniform processes such as weathering or plate tectonics.
Catastrophism suggests that features on Earth can be explained by sudden, short events. Such as Noah's flood or a meteorite impact.
So, what theory do you like best and why?
Uniformitarianism or catastrophism?
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Re: Uniformitarianism or catastrophism?
Post #101[Replying to DrNoGods in post #100]
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I know they say that not much uranium is in the core. But the reason they give is that uranium IV oxide is not soluble. I don't understand why they would say that and they really did not give the reason. The article simply said that it was because it was not soluble.uggests that U4+ can be bound up in aluminous CaSiO3 perovskite in the lower mantle. It can replace Ca+2 ions efficiently in the presence of Al. But there is too little U overall in the mantle, and similarly for the core people seem to believe, that it would not contribute much to the overall density of the core.
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Re: Uniformitarianism or catastrophism?
Post #102I do not think either one is true for the whole world. Some things are shaped over time and some things are shaped by catastrophic events.
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Re: Uniformitarianism or catastrophism?
Post #103Lyell himself discussed catastrophic change, while noting that most of the changes he found in the rocks was more gradual. The question poses a false dichotomy, since uniformitarianism includes both sudden and gradual change in the theory.
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Re: Uniformitarianism or catastrophism?
Post #104[Replying to The Barbarian in post #103]
Lyell my have thought that but the rocks do not show that.Lyell himself discussed catastrophic change, while noting that most of the changes he found in the rocks was more gradual. The question poses a false dichotomy, since uniformitarianism includes both sudden and gradual change in the theory.
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Re: Uniformitarianism or catastrophism?
Post #105Lyell himself discussed catastrophic change, while noting that most of the changes he found in the rocks was more gradual. The question poses a false dichotomy, since uniformitarianism includes both sudden and gradual change in the theory.
One place were varves have been studied for decades is below a deep lake in Japan: Lake Suigetsu. Here a varve chronology stretching back well over 50,000 years has been established.
An important summary of the significance of this varve chronology can be found in an open access article from Science here with a summary from Nature magazine here. For several decades, varve chronologies have been featured as clear evidence of an ancient Earth. The evidence from varves presents a formidable challenge to young-earth creationists (YECs) and their assertion that scientific evidence, properly interpreted, points to a young earth. Though a well-worn example, this recent work pushing the varve chronology to close to 60,000 year bears reviewing in light of how YECs have responded in the past to this challenging data.
https://thenaturalhistorian.com/2012/11 ... eationism/
It's notable that this set of varves validates Lyell's finding of both gradual change and periodic episodes of catastrophic change. Occasional volcanic eruptions have left their records in layers of tephra interspersed with gradual seasonal changes.
The Karoo basin in South Africa is one of the places on Earth where continuous change has been documented in the rocks for hundreds of millions of years:
The area plays a crucial role in revealing the distant origin of mammals, tortoises and dinosaurs. It also covers two great extinction events, the end-Permian (252 million years ago) and the end-Triassic (200 million years ago).
Because of its continuity of deposition, the Karoo provides not only a historical record of biological change over this period of Earth’s history, but also a means to test theories of evolutionary processes over long periods of time.
The 400,000 sq km area is internationally noted for its record of fossil therapsid “mammal-like” reptiles. These chart anatomical changes on the path to mammals from their early tetrapod forebears.
https://theconversation.com/why-south-a ... land-43045
The YE argument requires that the "geologic column" documenting an ancient Earth, does not actually exist in any one place. However the entire column, covering every major age from the Precambrian upward exists (for example) in North Dakota:
http://www.talkorigins.org/faqs/geocolumn/
The Atlantic Ocean is about 4400 km across. It was formed by an upwelling of magma at the Mid-Atlantic ridge. It enlarges by a few centimeters a year. Samples of rock taken difference distances from the ridge have been dated and confirm that this process has been going on for many millions of years.
And much more.
No, that's wrong. For example, we can show lake varves with gradual accumulations for tens of thousands of years of continuous change. Varves show two layers a year, one light one and one dark one. Learn about it here:EarthScienceguy wrote: ↑Thu Feb 02, 2023 12:45 pmLyell my have thought that but the rocks do not show that.
One place were varves have been studied for decades is below a deep lake in Japan: Lake Suigetsu. Here a varve chronology stretching back well over 50,000 years has been established.
An important summary of the significance of this varve chronology can be found in an open access article from Science here with a summary from Nature magazine here. For several decades, varve chronologies have been featured as clear evidence of an ancient Earth. The evidence from varves presents a formidable challenge to young-earth creationists (YECs) and their assertion that scientific evidence, properly interpreted, points to a young earth. Though a well-worn example, this recent work pushing the varve chronology to close to 60,000 year bears reviewing in light of how YECs have responded in the past to this challenging data.
https://thenaturalhistorian.com/2012/11 ... eationism/
It's notable that this set of varves validates Lyell's finding of both gradual change and periodic episodes of catastrophic change. Occasional volcanic eruptions have left their records in layers of tephra interspersed with gradual seasonal changes.
The Karoo basin in South Africa is one of the places on Earth where continuous change has been documented in the rocks for hundreds of millions of years:
The area plays a crucial role in revealing the distant origin of mammals, tortoises and dinosaurs. It also covers two great extinction events, the end-Permian (252 million years ago) and the end-Triassic (200 million years ago).
Because of its continuity of deposition, the Karoo provides not only a historical record of biological change over this period of Earth’s history, but also a means to test theories of evolutionary processes over long periods of time.
The 400,000 sq km area is internationally noted for its record of fossil therapsid “mammal-like” reptiles. These chart anatomical changes on the path to mammals from their early tetrapod forebears.
https://theconversation.com/why-south-a ... land-43045
The YE argument requires that the "geologic column" documenting an ancient Earth, does not actually exist in any one place. However the entire column, covering every major age from the Precambrian upward exists (for example) in North Dakota:
http://www.talkorigins.org/faqs/geocolumn/
The Atlantic Ocean is about 4400 km across. It was formed by an upwelling of magma at the Mid-Atlantic ridge. It enlarges by a few centimeters a year. Samples of rock taken difference distances from the ridge have been dated and confirm that this process has been going on for many millions of years.
And much more.