Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina)
Summary Permafrost desiccates and indurates soil horizons. During summer, the perennially frozen ground under the active thawed layer creates confined conditions, Whereas in winter the closed system between the permafrost and the freezing front migrating downwards leads to irreversible changes in th...
Published in: | European Journal of Soil Science |
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Online Access: | http://dx.doi.org/10.1046/j.1365-2389.1998.4930367.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2389.1998.4930367.x http://onlinelibrary.wiley.com/wol1/doi/10.1046/j.1365-2389.1998.4930367.x/fullpdf |
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crwiley:10.1046/j.1365-2389.1998.4930367.x 2024-06-02T08:13:03+00:00 Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina) VOGT, T. LARQUÉ, P. 1998 http://dx.doi.org/10.1046/j.1365-2389.1998.4930367.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2389.1998.4930367.x http://onlinelibrary.wiley.com/wol1/doi/10.1046/j.1365-2389.1998.4930367.x/fullpdf en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor European Journal of Soil Science volume 49, issue 3, page 367-376 ISSN 1351-0754 1365-2389 journal-article 1998 crwiley https://doi.org/10.1046/j.1365-2389.1998.4930367.x 2024-05-03T11:14:24Z Summary Permafrost desiccates and indurates soil horizons. During summer, the perennially frozen ground under the active thawed layer creates confined conditions, Whereas in winter the closed system between the permafrost and the freezing front migrating downwards leads to irreversible changes in the soil structure and to transformation and neoformation of minerals. Two examples were studied by field observation and laboratory analyses (optical microscopy, scanning electron microscopy, X‐ray diffractometry, transmission electron microscopy and analytical electron microscopy). In Transbaikalia (southeastern Siberia) a Pleistocene cryogenic slope deposit on syenite contains detrital clays (chlorite, illite), but neoformed ferroan smectites dominate. In Patagonia, centimetre‐sized silica concretions containing spongy and spheroidal opal occur in alluvium ascribed to cold Pleistocene periods. They seem to have formed from primary detrital smectite that was transformed to fibrous clay (sepiolite) then to acicular opal, and eventually to spheroidal opal. The neoformed opal contains 27% magnesium. These features occur systematically within fossil cryoturbations not related to present conditions. It appears that clay transformation and neoformation can happen at temperatures far lower than 0°C. Article in Journal/Newspaper permafrost Siberia Wiley Online Library Argentina Patagonia European Journal of Soil Science 49 3 367 376 |
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Open Polar |
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Wiley Online Library |
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crwiley |
language |
English |
description |
Summary Permafrost desiccates and indurates soil horizons. During summer, the perennially frozen ground under the active thawed layer creates confined conditions, Whereas in winter the closed system between the permafrost and the freezing front migrating downwards leads to irreversible changes in the soil structure and to transformation and neoformation of minerals. Two examples were studied by field observation and laboratory analyses (optical microscopy, scanning electron microscopy, X‐ray diffractometry, transmission electron microscopy and analytical electron microscopy). In Transbaikalia (southeastern Siberia) a Pleistocene cryogenic slope deposit on syenite contains detrital clays (chlorite, illite), but neoformed ferroan smectites dominate. In Patagonia, centimetre‐sized silica concretions containing spongy and spheroidal opal occur in alluvium ascribed to cold Pleistocene periods. They seem to have formed from primary detrital smectite that was transformed to fibrous clay (sepiolite) then to acicular opal, and eventually to spheroidal opal. The neoformed opal contains 27% magnesium. These features occur systematically within fossil cryoturbations not related to present conditions. It appears that clay transformation and neoformation can happen at temperatures far lower than 0°C. |
format |
Article in Journal/Newspaper |
author |
VOGT, T. LARQUÉ, P. |
spellingShingle |
VOGT, T. LARQUÉ, P. Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina) |
author_facet |
VOGT, T. LARQUÉ, P. |
author_sort |
VOGT, T. |
title |
Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina) |
title_short |
Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina) |
title_full |
Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina) |
title_fullStr |
Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina) |
title_full_unstemmed |
Transformations and neoformations of clay in the cryogenic environment: examples from Transbaikalia (Siberia) and Patagonia (Argentina) |
title_sort |
transformations and neoformations of clay in the cryogenic environment: examples from transbaikalia (siberia) and patagonia (argentina) |
publisher |
Wiley |
publishDate |
1998 |
url |
http://dx.doi.org/10.1046/j.1365-2389.1998.4930367.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2389.1998.4930367.x http://onlinelibrary.wiley.com/wol1/doi/10.1046/j.1365-2389.1998.4930367.x/fullpdf |
geographic |
Argentina Patagonia |
geographic_facet |
Argentina Patagonia |
genre |
permafrost Siberia |
genre_facet |
permafrost Siberia |
op_source |
European Journal of Soil Science volume 49, issue 3, page 367-376 ISSN 1351-0754 1365-2389 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1046/j.1365-2389.1998.4930367.x |
container_title |
European Journal of Soil Science |
container_volume |
49 |
container_issue |
3 |
container_start_page |
367 |
op_container_end_page |
376 |
_version_ |
1800759685381357568 |