Fallen ash has a story to tell

Area covered by tephra deposit south of Kīlauea Caldera described in text. Dots show places where the average particle size in the deposit was examined. Black lines connect equal average particle diameters; heavy black lines indicate diameters of 6 mm (0.2 in.) and 3 mm (0.1 in.) discussed in text. A and B indicate landing location of the two tracked particles. Red lines show hypothetical pathways of the particles as they were rising into the air, and green lines, hypothetical pathways as they were falling.