ISSN:
1432-0967
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
Notes:
Abstract Datations of ancient lavas from the Chaîne des Puys through the 230Th-238U radioactive disequilibrium method confirm the eruption of several basaltic or slightly differentiated lavas around 40,000 years ago. The study of (230Th/232Th)0 initial ratios of these lava flows clearly demonstrates the influence of a crustal contamination of magmas superimposed to crystal fractionation. This contamination probably affects many trace elements, in particular, U, Th and Sr. A model based on the (230Th/232Th)0 initial ratio variations of non-contaminated lavas permits to consider that the first eruptions in the Chaîne des Puys could have occurred about 100,000 years ago.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00371684
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