Water flowing from hot springs near volcanoes often contains a mixture of meteoric water that has percolated underground and a deeper component known as magmatic water. Researchers at the University of Tsukuba used numerical simulations and isotopic data to show that magmatic water in hot springs an d volcanic gases around Kussharo Caldera, Hokkaido, originates from the subducting Pacific Plate, which descends from the Kuril Trench to a depth of 125 kilometers (78 miles). The paper is published in the Journal of Volcanology and Geothermal Research. ...read more read less