Fig. 12
From: Physical characteristics of scoriae and ash from 2014–2015 eruption of Aso Volcano, Japan
Permeability measurement of powder-like ash. a Required pressure difference to cause a certain areal flow rate. The blue curve shows the measurement with the empty sieve, and the red curve shows that with the ash-filled sieve. b The difference between the measured pressures in (a). c Calculated permeability with a linear assumption