The Formation and Recharge of the Verkhne-Yuriev Thermal Springs, Paramushir Island, Kuril Islands

The Verkhne-Yuriev Springs have an output of chlorides among the highest worldwide. We discuss the influence of fault zones on the emplacement of magmatic material that provides at the same time for volcanic and geothermal activities in the area of study. An integrated analysis of geological structure, geophysical and geochemical isotope data, as well as voxel (3D) simulation, suggested a model to describe the Ebeko–Yuriev hydrothermal magmatic system. The interior of the hydrothermal magmatic system situated in the area of Ebeko Volcano contains subvolcanic intrusive bodies that were emplaced at different times. These bodies supply heat to the system. Magma rises to the ground surface along a weakened NW striking fault zone and emerges at the surface where the zone is intersected by a NNE striking fault maintaining the activity of Ebeko Volcano. At the intersections of the NW fault and the zones of subparallel NNE faults, magmatic material that has not reached the ground surface makes subvolcanic intrusive bodies (sills and dikes) that provide heat to the hydrothermal system.