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This article is about d-o-18 as a proxy; there is no need to make the "cycles" important, its the variations (which don't have to be, and often aren't at all cyclic) that are of interest. So I'd like to move it to just Oxygen isotope ratio.
Also, it should cover the proxy in general, not just in calcite.
Also, there is a lot of overlap with Proxy (climate).
William M. Connolley ( talk) 20:50, 25 January 2008 (UTC)
Why? All the issues discussed in the previous comments and more. E.g.: it contains incorrect definitions and/or descriptions. like that a molecule contains the three isotopes. This article should be deleted and the article oxygen-18 corrected and expanded. That is, if you think that the this wiki should be regarded as a serious reference source. Jclerman ( talk) 01:03, 7 April 2008 (UTC)
The 18O/16O ratio provides a record of ancient water temperature. Water 10 to 15 degrees Celsius (18 to 27 degrees Fahrenheit) cooler than present represents glaciation. Precipitation and therefore glacial ice contain water with a low 18O content. Since large amounts of 16O water are being stored as glacial ice, the 18O content of oceanic water is high. Water up to 5 degrees Celsius (9 °F) warmer than today represents an interglacial, when the 18O content is lower. A plot of ancient water temperature over time indicates that climate has varied cyclically, with large cycles and harmonics, or smaller cycles, superimposed on the large ones. This technique has been especially valuable for identifying glacial maxima and minima in the Pleistocene.
Jclerman ( talk) 17:12, 4 June 2008 (UTC)
Oxygen isotope ratio cycles are cyclical variations in the ratio of the mass of oxygen with an atomic weight of 18 to the mass of oxygen with an atomic weight of 16 present in some substance, such as polar ice or calcite in ocean core samples. The ratio is linked to water temperature of ancient oceans, which in turn reflects ancient climates. Cycles in the ratio mirror climate changes in geologic history.
Jclerman ( talk) 17:15, 4 June 2008 (UTC)
I understand the concept and yet found myself confused after reading the article. It really needs a cleanup. —Preceding unsigned comment added by 67.176.78.164 ( talk) 21:41, 10 April 2010 (UTC)
Because H216O requires less energy to vaporize, and is more likely to diffuse to the liquid phase, the first water vapor formed during evaporation of liquid water is enriched in H216O, and the residual liquid is enriched in H218O. When water vapor condenses into liquid, H218O preferentially enters the liquid, while H216O is concentrated in the remaining vapor.
Latent Heat of vapourization is increased by the presence of the heavier Oxygen-18 isotopes in that it makes the Water molecule ~ 10% heavier (Molecular Weight 18 increased to 20). The predominant forces that set the melting point and boiling point of water arise from Hydrogen Bonding which are unrelated to molecular mass. Therefore melting point and boiling point is unaffected by the different isotopes of oxygen.
While it is true that water containing O-16 will vapourise more quickly, this water will also condense more quickley because it needs to give up less heat to do so. The statement, "When water vapor condenses into liquid, H218O preferentially enters the liquid," is not true. — Preceding unsigned comment added by Murray Peterson ( talk • contribs) 13:18, 15 July 2020 (UTC)
This is the
talk page for discussing improvements to the
Oxygen isotope ratio cycle article. This is not a forum for general discussion of the article's subject. |
Article policies
|
Find sources: Google ( books · news · scholar · free images · WP refs) · FENS · JSTOR · TWL |
This article was nominated for deletion on 30 April 2008. The result of the discussion was keep. |
This article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||||||||||||
|
This article is about d-o-18 as a proxy; there is no need to make the "cycles" important, its the variations (which don't have to be, and often aren't at all cyclic) that are of interest. So I'd like to move it to just Oxygen isotope ratio.
Also, it should cover the proxy in general, not just in calcite.
Also, there is a lot of overlap with Proxy (climate).
William M. Connolley ( talk) 20:50, 25 January 2008 (UTC)
Why? All the issues discussed in the previous comments and more. E.g.: it contains incorrect definitions and/or descriptions. like that a molecule contains the three isotopes. This article should be deleted and the article oxygen-18 corrected and expanded. That is, if you think that the this wiki should be regarded as a serious reference source. Jclerman ( talk) 01:03, 7 April 2008 (UTC)
The 18O/16O ratio provides a record of ancient water temperature. Water 10 to 15 degrees Celsius (18 to 27 degrees Fahrenheit) cooler than present represents glaciation. Precipitation and therefore glacial ice contain water with a low 18O content. Since large amounts of 16O water are being stored as glacial ice, the 18O content of oceanic water is high. Water up to 5 degrees Celsius (9 °F) warmer than today represents an interglacial, when the 18O content is lower. A plot of ancient water temperature over time indicates that climate has varied cyclically, with large cycles and harmonics, or smaller cycles, superimposed on the large ones. This technique has been especially valuable for identifying glacial maxima and minima in the Pleistocene.
Jclerman ( talk) 17:12, 4 June 2008 (UTC)
Oxygen isotope ratio cycles are cyclical variations in the ratio of the mass of oxygen with an atomic weight of 18 to the mass of oxygen with an atomic weight of 16 present in some substance, such as polar ice or calcite in ocean core samples. The ratio is linked to water temperature of ancient oceans, which in turn reflects ancient climates. Cycles in the ratio mirror climate changes in geologic history.
Jclerman ( talk) 17:15, 4 June 2008 (UTC)
I understand the concept and yet found myself confused after reading the article. It really needs a cleanup. —Preceding unsigned comment added by 67.176.78.164 ( talk) 21:41, 10 April 2010 (UTC)
Because H216O requires less energy to vaporize, and is more likely to diffuse to the liquid phase, the first water vapor formed during evaporation of liquid water is enriched in H216O, and the residual liquid is enriched in H218O. When water vapor condenses into liquid, H218O preferentially enters the liquid, while H216O is concentrated in the remaining vapor.
Latent Heat of vapourization is increased by the presence of the heavier Oxygen-18 isotopes in that it makes the Water molecule ~ 10% heavier (Molecular Weight 18 increased to 20). The predominant forces that set the melting point and boiling point of water arise from Hydrogen Bonding which are unrelated to molecular mass. Therefore melting point and boiling point is unaffected by the different isotopes of oxygen.
While it is true that water containing O-16 will vapourise more quickly, this water will also condense more quickley because it needs to give up less heat to do so. The statement, "When water vapor condenses into liquid, H218O preferentially enters the liquid," is not true. — Preceding unsigned comment added by Murray Peterson ( talk • contribs) 13:18, 15 July 2020 (UTC)