Volcanoes

1. Volcanoes

2. Tephra • Tephra is fragmental material produced by a volcanic eruption regardless of composition, fragment size or emplacement mechanism. • Tephra fragments are classified by size: • Ash – particles smaller than 2 mm (0.08 inches) in diameter, • Lapilli or volcanic cinders – between 2 and 64 mm (0.08 and 2.5 inches) in diameter, • Volcanic bombs or volcanic blocks – larger than 64 mm (2.5 inches) in diameter. • 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".

3. Tephra • Step 1 – Identify the elements of an eruption • Step 2 – Some of the elements can be grouped together into a set. Which ones? • Step 3 – Attempt to label your groupings • Step 4 – “Tephra” is a Greek word. What do you think it means?

5. Tephra

6. Group Task • An archeologist makes a discovery of a skeleton near a previously unknown volcano. How can the archeologist determine if an eruption was to blame for the death? • Hint: tephrochronology

7. Name That Tephra • 100 pts: 2mm or smaller • 200 pts: 2mm – 64 mm • 100 pts: larger than 64 mm

8. Clicker Questions Which of the following describes lapilli? • 2mm or smaller • 2mm – 64 mm • larger than 64 mm

9. Haiku A haiku is a poem with three lines: 5 syllables 7 syllables 5 syllabus Write a haiku about tephra