Abstract

Precise dating of very young (≤10 000 yr) silicic volcanic rocks can be achieved by measurements of 230Th-238U disequilibria in accessory minerals such as apatite and zircon. It is illustrated here by the isochron age of 12 000 ± 1000 yr obtained on a trachyte from the Puy de Dôme (French Massif Central). The crystallization age is virtually the same as the eruption age determined by thermoluminescence and 14C dating. This indicates a short time interval (a few centuries at most) between crystallization and eruption in such small volume silicic magmas.

First Page Preview

First page PDF preview
You do not currently have access to this article.