11. Volcanoes: emissions from volcanic eruptions

Question 1

lava flow

Answer 1

• hot molten / semi-fluid rock erupted from volcano / fissure
• about 1000°
• destroys everything in path
• e.g. Lava flow from Hawaiian Volcano destroyed everything it came in contact w/ including a car

Question 2

ash fall

Answer 2

• combi of fine particles made of rocks, volcanic glass, & minerals ejected into atmosphere during violent explosive eruption
• cause thunder & lightning storms, if carried high enough it can deflect sunlight, cooling temp. on Earth –> creating volcanic winter
• e.g. spread of ashfall from Mt. Pinatubo, Philippines reached Sg & surrounding regions

Question 3

volcanic bombs

Answer 3

• chunk of rock spewed out of volcano, less than 65mm in diameter
• heavy & travel at high speed –> dangerous for people
• e.g. 6 people killed at Galeras volcano, Columbia, 1993, several injured

Question 4

pyroclastic flow

Answer 4

• mass of ash, rock fragments, & volcanic bombs ejected during eruption –> flowing up to 700km/h
• formed when pyroclasts mix w/ very hot gases ejected during volcanic eruptions
• e.g. Pompeii in 79 A.D., pyroclastic flow covered whole city, 2000 people died