Volcanoes

• What do you know about volcanoes?

• What would you like to know?

Hawaii

Volcanoes can be Active, Dormant or Extinct

Active

Dormant

Extinct

vent

cone

magma chamber

Pipe

(Conduit)

Cold Crust

Ocean

Hot Melt

Hot Mantle

CoolerMantle

Volcanoes that erupt like yours are called Effusive or Shield volcanoes

The lava:• Is runny• The lava flows a long way• Has some bubbles• Forms volcanoes that are wider than they are tall

An example is:

Mauna Loa, Hawaii

Effusive volcanoes

Explosive Volcanoes

We are now going to show you what an explosive volcano is like.Watch carefully and you will notice some differences in the way it erupts from the way your volcano erupted.

USGS/Hawaiian Volcano ObservatoryPhoto by J.D. Griggs

Activity

magma magma

Hawaii

Courtesy of www.swisseduc.ch

Ash and rocks are thrown into the air

Thick lava flows

RoughLots of pieces

Smooth or Ropy

Courtesy of A. Rust

Courtesy of A. Rust

• We have brought along a collection of real volcanic rock from Bristol University for you to investigate

• Look carefully- • Can you see any bubbles in the rock?• Can you find any crystals?• Can you see anything that has melted in the lava?• Can you find a volcanic bomb?• Can you find some wiggly lava?

• We have brought along a few rocks that are not from Volcanoes- can you work out which ones they are?

What is a volcano? Mountains that erupt .

A dormant volcano is: awake asleep ________ chamber

V____

Conduit

Cone

Why do volcanoes erupt? Hot magma wants to go: up down

How do volcanoes erupt? Two types: e and effusive

What helps make explosive volcanoes erupt? .

Do effusive volcanoes have runny or sticky lava? .

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