The evolution of hydrothermal alteration in glassy and variably palagonitized tuff, erupted as tephra in 1963 – 1964 on Surtsey, an island built in the offshore extension of Iceland’s southeast rift zone, is documented through a comparative petrographic ...

Glacier runoff and melt from volcanic and geothermal activity accumulates in glacier dammed lakes in glaciated areas around the world. These lakes eventually drain, creating hazardous subglacial floods that are usually only confirmed after they exit ...