Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China
A Neoproterozoic succession of glaciomarine deposits of probably Sturtian age is preserved on the Yangtze Platform in South China. At that time, the South China block was located in intermediate to low paleolatitudes at ca. 40°. The snowball Earth hypothesis offers one possible explanation for the o...
Main Authors: | , , , |
---|---|
Other Authors: | |
Format: | Text |
Language: | English |
Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.982 http://www.uni-muenster.de/GeoPalaeontologie/Geologie/Sedi/pdf/Dobrzinski+et+al_2004_Geochemical+climate+proxies+applied+to+the+Neoproterozoic+glacial+succession+on+the+Yangtze+Platform,+South+China.pdf |
id |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.513.982 |
---|---|
record_format |
openpolar |
spelling |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.513.982 2023-05-15T18:18:46+02:00 Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China Nicole Dobrzinski Heinrich Bahlburg Harald Strauss Qirui Zhang The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.982 http://www.uni-muenster.de/GeoPalaeontologie/Geologie/Sedi/pdf/Dobrzinski+et+al_2004_Geochemical+climate+proxies+applied+to+the+Neoproterozoic+glacial+succession+on+the+Yangtze+Platform,+South+China.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.982 http://www.uni-muenster.de/GeoPalaeontologie/Geologie/Sedi/pdf/Dobrzinski+et+al_2004_Geochemical+climate+proxies+applied+to+the+Neoproterozoic+glacial+succession+on+the+Yangtze+Platform,+South+China.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://www.uni-muenster.de/GeoPalaeontologie/Geologie/Sedi/pdf/Dobrzinski+et+al_2004_Geochemical+climate+proxies+applied+to+the+Neoproterozoic+glacial+succession+on+the+Yangtze+Platform,+South+China.pdf text ftciteseerx 2016-01-08T09:47:13Z A Neoproterozoic succession of glaciomarine deposits of probably Sturtian age is preserved on the Yangtze Platform in South China. At that time, the South China block was located in intermediate to low paleolatitudes at ca. 40°. The snowball Earth hypothesis offers one possible explanation for the occurrence of low latitude tillites. The hypothesis is largely based on geological and geochemical observation made in deposits underlying or overlying such tillites on several continents. In con-trast our study focuses on evidence offered by the tillites themselves. We use major, and trace rare element geochemistry to evaluate the environmental conditions prevailing during the glaciation. Of particular interest are the intensity of chemical weathering and the relative degree of oxygenation of Neoproterozoic (Nanhuan-Sinian) marine bottom waters. CIA values were obtained from preglacial sand- and siltstones, the matrix of the glacial deposits, fine-grained clastic sediments of a unit intercalated in the glacial succession, and postglacial siltstones and black shales. The data indicate relatively low degrees of chemical weathering for the glacial deposits. In contrast, pre-and postglacial deposits display comparatively elevated levels. This is also true for the intercalated unit, which we interpret as the product of a warmer and more humid interglacial period. Data for S/TOC, U/Th, Cd, Mo, and the Ceanom of the glacioma-rine samples indicate the presence of oxic bottom waters during the glaciation. The snowball Earth hypothesis predicts the shutdown of chemical weathering on the con-tinents and complete anoxia of the global ocean largely covered by sea ice for sev-eral million years. The geochemical record of the Neoproterozoic tillites on the Yangtze Platform is difficult to reconcile with the snowball Earth hypothesis. 1. Text Sea ice Unknown |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
ftciteseerx |
language |
English |
description |
A Neoproterozoic succession of glaciomarine deposits of probably Sturtian age is preserved on the Yangtze Platform in South China. At that time, the South China block was located in intermediate to low paleolatitudes at ca. 40°. The snowball Earth hypothesis offers one possible explanation for the occurrence of low latitude tillites. The hypothesis is largely based on geological and geochemical observation made in deposits underlying or overlying such tillites on several continents. In con-trast our study focuses on evidence offered by the tillites themselves. We use major, and trace rare element geochemistry to evaluate the environmental conditions prevailing during the glaciation. Of particular interest are the intensity of chemical weathering and the relative degree of oxygenation of Neoproterozoic (Nanhuan-Sinian) marine bottom waters. CIA values were obtained from preglacial sand- and siltstones, the matrix of the glacial deposits, fine-grained clastic sediments of a unit intercalated in the glacial succession, and postglacial siltstones and black shales. The data indicate relatively low degrees of chemical weathering for the glacial deposits. In contrast, pre-and postglacial deposits display comparatively elevated levels. This is also true for the intercalated unit, which we interpret as the product of a warmer and more humid interglacial period. Data for S/TOC, U/Th, Cd, Mo, and the Ceanom of the glacioma-rine samples indicate the presence of oxic bottom waters during the glaciation. The snowball Earth hypothesis predicts the shutdown of chemical weathering on the con-tinents and complete anoxia of the global ocean largely covered by sea ice for sev-eral million years. The geochemical record of the Neoproterozoic tillites on the Yangtze Platform is difficult to reconcile with the snowball Earth hypothesis. 1. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Nicole Dobrzinski Heinrich Bahlburg Harald Strauss Qirui Zhang |
spellingShingle |
Nicole Dobrzinski Heinrich Bahlburg Harald Strauss Qirui Zhang Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China |
author_facet |
Nicole Dobrzinski Heinrich Bahlburg Harald Strauss Qirui Zhang |
author_sort |
Nicole Dobrzinski |
title |
Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China |
title_short |
Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China |
title_full |
Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China |
title_fullStr |
Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China |
title_full_unstemmed |
Geochemical Climate Proxies Applied to the Neoproterozoic Glacial Succession on the Yangtze Platform, South China |
title_sort |
geochemical climate proxies applied to the neoproterozoic glacial succession on the yangtze platform, south china |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.982 http://www.uni-muenster.de/GeoPalaeontologie/Geologie/Sedi/pdf/Dobrzinski+et+al_2004_Geochemical+climate+proxies+applied+to+the+Neoproterozoic+glacial+succession+on+the+Yangtze+Platform,+South+China.pdf |
genre |
Sea ice |
genre_facet |
Sea ice |
op_source |
http://www.uni-muenster.de/GeoPalaeontologie/Geologie/Sedi/pdf/Dobrzinski+et+al_2004_Geochemical+climate+proxies+applied+to+the+Neoproterozoic+glacial+succession+on+the+Yangtze+Platform,+South+China.pdf |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.513.982 http://www.uni-muenster.de/GeoPalaeontologie/Geologie/Sedi/pdf/Dobrzinski+et+al_2004_Geochemical+climate+proxies+applied+to+the+Neoproterozoic+glacial+succession+on+the+Yangtze+Platform,+South+China.pdf |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766195458554724352 |