(Table 1) Boron, carbon, magnesium and calcium isotope data, post-Marinoan Neoproterozoic carbonate sections, Namibia
Cobertura |
MEDIAN LATITUDE: -19.586229 * MEDIAN LONGITUDE: 14.336760 * SOUTH-BOUND LATITUDE: -20.199167 * WEST-BOUND LONGITUDE: 13.995608 * NORTH-BOUND LATITUDE: -19.256564 * EAST-BOUND LONGITUDE: 15.016164 * MINIMUM SECTION, height: 0.0 m * MAXIMUM SECTION, height: 300.3 m |
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Data(s) |
10/07/2014
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Resumo |
A marked ocean acidification event and elevated atmospheric carbon dioxide concentrations following the extreme environmental conditions of the younger Cryogenian glaciation have been inferred from boron isotope measurements. Calcium and magnesium isotope analyses offer additional insights into the processes occurring during this time. Data from Neoproterozoic sections in Namibia indicate that following the end of glaciation the continental weathering flux transitioned from being of mixed carbonate and silicate character to a silicate-dominated one. Combined with the effects of primary dolomite formation in the cap dolostones, this caused the ocean to depart from a state of acidification and return to higher pH after climatic amelioration. Differences in the magnitude of stratigraphic isotopic changes across the continental margin of the southern Congo craton shelf point to local influences modifying and amplifying the global signal, which need to be considered in order to avoid overestimation of the worldwide chemical weathering flux. |
Formato |
text/tab-separated-values, 419 data points |
Identificador |
https://doi.pangaea.de/10.1594/PANGAEA.833928 doi:10.1594/PANGAEA.833928 |
Idioma(s) |
en |
Publicador |
PANGAEA |
Relação |
Kasemann, Simone A; Hawkesworth, Chris J; Prave, Anthony R; Fallick, Anthony E; Pearson, Paul N (2005): Boron and calcium isotope composition in Neoproterozoic carbonate rocks from Namibia: evidence for extreme environmental change. Earth and Planetary Science Letters, 231(1-2), 73-86, doi:10.1016/j.epsl.2004.12.006 Kasemann, Simone A; Prave, Anthony R; Fallick, Anthony E; Hawkesworth, Chris J; Hoffmann, Karl-Heinz (2010): Neoproterozoic ice ages, boron isotopes, and ocean acidification: Implications for a snowball Earth. Geology, 38(9), 775-778, doi:10.1130/G30851.1 |
Direitos |
CC-BY: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted |
Fonte |
Supplement to: Kasemann, Simone A; Pogge von Strandmann, Philip A E; Prave, Anthony R; Fallick, Anthony E; Elliott, Tim; Hoffmann, Karl-Heinz (2014): Continental weathering following a Cryogenian glaciation: Evidence from calcium and magnesium isotopes. Earth and Planetary Science Letters, 396, 66-77, doi:10.1016/j.epsl.2014.03.048 |
Palavras-Chave | #Center for Marine Environmental Sciences; delta 11B; delta 13C, carbonate; delta 18O, carbonate; delta 26Mg; delta 44/40 Ca; Event label; Finnigan TRITON thermal ionization mass spectrometer (TIMS); Fransfontein; Khowarib; Lithologic unit/sequence; Lithology/composition/facies; MARUM; NW Namibia; Ombaatjie; PROFILE; Profile sampling; Sample code/label; SECTION, height; Uncertainty |
Tipo |
Dataset |