Precise and reliable argon geochronology of high- and ultra high-pressure metamorphic rocks

点击翻译按钮获取中文摘要

Basic research was carried out to reveal the metamorphism and the subsequent exhumation process of high and ultra-high pressure metamorphic rocks. In a part of the achievement, we set up the micro-probe Ar-Ar facilities equipped with UV laser. With analyses using the new facilities and the conventional ones, we examined the relationships among geological structure, thermal structure and phengite ages of the high-pressure metamorphic belts in Pacific type orogenic belt. This approach revealed two different exhumation processes of the belts. We interpreted the differences are due to the natures of oceanic plate boundaries that subduct into the deeper part of subduction zone.