Information AboutTephra |
| CATEGORIES ABOUT TEPHRA | |
| petrology | |
| volcanology | |
| igneous rocks | |
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Volcanologists also refer to airborne fragments as ''pyroclasts'' or sometimes just '''''clasts'''''. Once clasts have fallen to the ground they remain as tephra unless hot enough to fuse together into Pyroclastic Rock or Tuff . The distribution of tephra following an eruption usually involves the largest boulders falling to the ground quickest and therefore closest to the vent, while smaller fragments travel further—ash can often travel for thousands of miles as it can stay in the Stratosphere for several weeks. Tephra fragments are classified by size:
The words "tephra" and "pyroclast" both derive from Greek . ''Tephra'' means "ash". ''Pyro'' means "fire" and ''klastos'' means "broken"; thus pyroclasts carry the connotation of "broken by fire". The use of tephra layers as temporal marker horizons is known as Tephrochronology . EXTERNAL LINKS |
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