A火山弹 C叶面上的火山灰 Figure 5.6 Tephra.A.Large spindle-shaped pyroclasts up to 50 cm in length cover the surface of a tephra cone on Haleakala volcano.Maul.B.Intermediate-sized tephra called lapilli cover the Kau Desert.Hawall.The coin is about I cm in diameter.C.Volcanic ash.the smallest-sized tephra.covers leaves in a garden in Anchorage.Alaska.fol- lowing the eruption of Mount Spurr. B火山砾