6-3: Volcanic Landforms - luisenok8.com€¦ · 6-3: Volcanic Landforms Lava and Ash Landforms •Shield Volcanoes •Cinder Cone Volcanoes •Composite Volcanoes •Lava Plateaus

6-3: Volcanic Landforms

6th Grade Earth Science

6-3: Volcanic Landforms Lava and Ash Landforms

• Shield Volcanoes • Cinder Cone

Volcanoes • Composite

Volcanoes • Lava Plateaus • Calderas • Soils from Lava

and Ash

6-3: Volcanic Landforms Shield Volcanoes

• Shield Volcanoes are broad and gently sloping.

• They form from one thin layer of lava flowing over another thin layer of lava, slowly building it up.

6-3: Volcanic Landforms Cinder Cones

• Cinder cones form when magma has enough silica.

• Ash, cinders, and bombs build a steep cone.

6-3: Volcanic Landforms Composite Volcanoes

• Composite Volcanoes are a combo of gentle and explosive eruptions.

• Explosions of ash are followed by layers of lava – this cycle happens over and over.

6-3: Volcanic Landforms Lava Plateaus

• Lava Plateaus form when large lava flows occur over and over, building up a high, flat area.

Columbia River Plateau

6-3: Volcanic Landforms Calderas

• Calderas form when the volcano collapses into its empty pipe and magma chamber.

Crater Lake, Oregon

6-3: Volcanic Landforms

6-3: Volcanic Landforms Soils from Lava and Ash

• The soils that form from lava and ash are some of the richest in the world.

• Often people settle next to volcanoes to farm.

6-3: Volcanic Landforms Landforms from Magma

• Volcanic Necks

• Dikes

• Sills

• Batholiths

6-3: Volcanic Landforms Volcanic Necks

• Volcanic necks form when the pipe of a volcano hardens.

• Then the volcano erodes away, leaving the hard rock in the pipe.

6-3: Volcanic Landforms Dikes

• Dikes form when magma forces itself between layers of rock.

• It hardens in the crack.

6-3: Volcanic Landforms

6-3: Volcanic Landforms

6-3: Volcanic Landforms

6-3: Volcanic Landforms Sills

• Sills form when magma squeezes between horizontal layers of rock.

• It hardens between the layers.

6-3: Volcanic Landforms Intrusions

• Dikes and sills are examples of igneous intrusions, magma that hardens underground.

• They are always younger than the surrounding rock.

6-3: Volcanic Landforms And finally … Batholiths

• Batholiths form when LARGE areas of magma cool inside the crust.

• Many large mountain ranges, like the Sierras, formed this way.

6-3: Volcanic Landforms

6-3: Volcanic Landforms

6-3: Volcanic Landforms Summary

1. Lava and ash give rise to many landforms, such as shield and composite volcanoes.

2. Magma underground cools to form many landforms as well, such as dikes, sills, and batholiths.