The Quaternary Kurobegawa Granite: an example of a deeply dissected resurgent pluton

Hisatoshi Ito,Kenji Horie,Koji Fukuma,Mami Takehara,Yoshiko Adachi,Aitor Cambeses,Mayuko Fukuyama,Takashi Kubo,Fernando Bea,Ryuji Yamada

doi:10.1038/s41598-021-01562-2

Abstract

The Quaternary Kurobegawa Granite, central Japan, is not only the youngest known granitic pluton exposed on the Earth’s surface, it is one of few localities where both Quaternary volcanics and related plutons are well exposed. Here, we present new zircon U–Pb ages together with whole rock and mineral geochemical data, revealing that the Kurobegawa Granite is a resurgent pluton that was emplaced following the caldera-forming eruption of the Jiigatake Volcanics at 1.55 ± 0.09 Ma. Following the eruption, the remnant magma chamber progressively cooled forming the voluminous Kurobegawa pluton in the upper crust (~ 6 km depth) until ~ 0.7 Ma when resurgence caused rapid uplift and erosion in the region. This is the first study to document the detailed spatiotemporal evolution of resurgent pluton for a Quaternary caldera system. Our new findings may contribute significantly to understanding the fate of active caldera systems that can produce supereruptions.

Highlights

Plutons are an important component of Earth’s lithosphere and it is vital to better understand how they are assembled in the crust
The Kurobegawa Granite is a rare example of a deeply dissected resurgent pluton associated with a Quaternary caldera system and that the resurgence itself played a major role in uplift and erosion
LA-ICP-MS zircon U–Pb ages from 35 sites were newly obtained in this study (Fig. 2; Supplementary Table S2)

Summary

Introduction

Plutons are an important component of Earth’s lithosphere and it is vital to better understand how they are assembled in the crust. We focus on Earth’s youngest exposed pluton, the Kurobegawa Granite in the Hida Mountain Range (HMR), central Japan (Fig. 1), to better understand pluton assembly. Ito et al.[16] provided zircon U–Pb age data from 35 localities associated with the Kurobegawa Granite (sensu lato) and revealed that it is the Earth’s youngest exposed pluton amalgamated starting at 10 Ma with multiple episodes of magmatic intrusion; the youngest at ca. We provide new zircon U–Pb ages and geochemical data to better understand the spatiotemporal petrogenetic intrusion history of the Kurobegawa pluton and its predecessor, the Jiigatake Volcanics. The Kurobegawa Granite is a rare example of a deeply dissected resurgent pluton associated with a Quaternary caldera system and that the resurgence itself played a major role in uplift and erosion

Methods

Results

Discussion

Conclusion