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| Titel |
Apatite U-Pb Thermochronology: A combined ID-TIMS and LA-ICP-MS study from southern Ecuador |
| VerfasserIn |
R. Cochrane, R. Spikings, D. Chew, J. Wotzlaw |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250071684
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| Zusammenfassung |
| A combination of U-Pb LA-ICP-MS and ID-TIMS analyses of apatite has been used to
investigate the high temperature (>450Ë C) thermal history of the Ecuadorian Andean
margin. The rocks of the Eastern Cordillera of Ecuador evolved via terrane collision and
accretion events, and active margin magmatism since the Early Jurassic. Low temperature
(0.5) reveal periods of: i) rapid
cooling (~240-220 Ma) through the Pb Partial Retention Zone (PRZ) shortly after
crystallization, ii) residence at temperatures lower than the PRZ throughout the Jurassic, iii)
reheating during 140-90 Ma, and iv) rapid cooling starting at 80-70 Ma. These
findings corroborate conclusions based on geochronological and sedimentological
data.
Additional in-situ age transects and age-depth profiling of apatite are scheduled to
determine the concentration distribution of radiogenic lead in the apatites, which will be used
to constrain further the mechanisms of lead loss.
References:
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detrital thermochronometric record. Journal of South American Earth Sciences 30. 121-133. |
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