Abstract
We investigated trace element and isotopic compositions of the post-caldera volcanic products from Aso volcano in order to constrain their compositional diversity and the genetic relationship with the caldera-forming magma. The results indicate that the compositional diversity of post-caldera volcanic products was probably generated from at least two different magma sources. Although the trace element compositions of the post-caldera products are similar to those of the caldera-forming pyroclastic products, the isotopic compositions of the former are quite difference from those of the latter. These observations imply that the post-caldera magma is not the remnant of the caldera-forming magma, but the newly generated magma after the caldera formation.
