Volcanoes6th grade quiz practice

Ms. Cooper’s class

What is the difference between Magma and Lava?

•Magma is melted rock inside the earth. Once it comes out of the earth, it’s called lava

•What do we call a volcano that is no longer able to erupt?

•extinct

•What do we call a volcano that has recently erupted?

•Active

•What do we call a volcano the are not active now, but may become active in the future?

•dormant

•What is the “Ring of Fire” and where

is it?

• A ring of volcanoes and earthquakes located where the oceanic crust of the Pacific Plate is subducting under other plates.

•How are volcanic island chains

formed?

•As a lithospheric plate moves over a hot spot, a series of volcanoes form

•What is the name for a flat and wide volcano that has low-silica magma with low or high levels of dissolved gas?

•Shield Volcano

•Where do Shield Volcanoes form?

•Over Oceanic Plates

•What kind of volcano has low-silica magma with high levels of dissolved gas that produce “fire fountain” eruptions?

•Cinder cone

•What kind of volcano that is formed by layers of silica-rich lava and ash is tall , explosive and cone-shaped?

•Composite Volcano

•Where do Composite

Volcanoes form?

•At Subduction zones

(convergent plate boundries)

•What kind of rocks are found

at shield volcanoes?

•Basalt

•What kind of rocks are found at

composite volcanoes?

•Andesite

• Rhyolite

•Granite

•Describe magma that is high in silica.

•High Viscosity: Thick, sticky (like peanut butter) forms composite volcanoes

•Describe magma that is low in silica.

•Low Viscosity: Runny, thin (like ketchup). Forms shield or cinder cone volcanoes.

•What is the name for a bowl shaped crater that forms on top of cinder cone volcanoes?

•Caldera

•How does cooling rate relate to crystal size in

the formation of igneous rocks?

•Slow cooling magma has time to form large crystals. Magma that cools quickly has smaller crystals.

fast cooling obsidian slow cooling granite