Increased rates of large-magnitude explosive eruptions in Japan in the late Neogene and Quaternary.

ABSTRACT: Tephra layers in marine sediment cores from scientific ocean drilling largely record high-magnitude silicic explosive eruptions in the Japan arc for up to the last 20 million years. Analysis of the thickness variation with distance of 180 tephra layers from a global data set suggests that the majority of the visible tephra layers used in this study are the products of caldera-forming eruptions with magnitude (M) > 6, considering their distances at the respective drilling sites to their likely volcanic sources. Frequency of visible tephra layers in cores indicates a marked increase in rates of large magnitude explosive eruptions at ∼8 Ma, 6-4 Ma, and further increase after ∼2 Ma. These changes are attributed to major changes in tectonic plate interactions. Lower rates of large magnitude exp

SUBMITTER: Mahony SH 

PROVIDER: S-EPMC5012118 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature