LOOK: Mayon Volcano emits PDCs anew

(Photos courtesy of Camalig, Albay Mayor Caloy Baldo / Facebook) MANILA, Philippines — Pyroclastic density currents (PDCs) at Mayon Volcano in Albay were observed anew on Wednesday, state volcanologists said. PDCs are fast-flowing hot ash, volcanic gases, and rock fragments that descend the volcano’s slopes when lava deposits collapse.  According to the Philippine Institute of