Floating pumice blocks from remote eruption in August ports near Tokyo,JAPAN

The mixed submarine -subaerial eruption of the volcano in last August,when a new lsland formed,still shows effects today:large amounts of floating pumice stones washed up on the shores of Greater Tokyo recently.

On other coasts in SW Japan,pumice rafts from the volcano have been a burden for a month and often impaired fishing and seafaring.

Pumice forms as highly viscous magma erupts with myriads of small gas bubbles trapped within the sticky liquid,which freezes to volcanic glass.It could be described as frozen lava foam.Due to its bubbly structure,it is often higher than water and thus floats.With time,water enters  the cavities by diffusion and through tiny cracks in the glassy walls around the bubbles but it can take months and even years until the pumice eventually will sink and form a deposit on the seafloor ,if it isn't washed up on the shore earlier.