Volcanoes :)

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what is contained in the gases released by the "Ring of Fire" volcanoes

Carbon 12

What substances make lava or magma sticky

Silica. The more it contains the thicker the lava is.

Runny magma or lava does not explode. WHY

The bubbles can escape the runny lava.

Where does the CO2 in the volcanic gases originate

The burning of the organisms from the ocean floor.

Why does magma in the mantle rise through the crust above it

The magma is less dense.

What is a Lava Flow

The spread of lava as it pours out of a vent.

How many Hot spot's created the Hawaiian islands

1 HOT SPOT

How many people have died in the last 200 yr because of the "Ring of Fire"

1 million

What is a Pipe

A long tube that extends from Earth's crust up through the top of the volcano, connecting the magma chamber to Earth's surface. Magma moves upward through the pipe.

What is Pyroclastic Flow

A mixture of hot gases, ash, cinders, and bombs that flow down the sides of a volcano when it erupts explosively.

What is a Volcano

A volcano is a mountain that forms in Earth's crust when molten material, or magma, reaches the surface.

What is a Magma Chamber

All volcanoes have a pocket of magma beneath the surface where the magma collects.

What is a Hot Spot

An area where material from deep within Earth's mantle rises to the crust and melts to form magma.

What is a Calderas

Are huge holes left by the collapse of volcanoes. A lake may form.

What is a Composite Volcano

Are tall, cone-shaped mountains in which layers of LAVA alternate with layers of ASH.

Why do gases appear in magma

Drop in pressure allows the gases to appear.

What Landforms Does Magma Create

Features formed by magma include volcanic necks, dikes, and stills, as well as dome mountains and batholiths.

What is a Volcanic Neck

Forms when magma hardens in a volcano's pipe and the surrounding rock later wears away.

What is a Dome Mountain

Forms when uplift pushes a large body of hardened magma toward the surface, which eventually becomes exposed.

What is a Cinder Cone Volcano

In a explosive eruption, ASH, CINDERS, and BOMBS can build up around the vent in a steep, cone-shaped hill or small mountain.

What is a Batholiths

Is a mass of rock formed when a large body of magma cools inside the crust.

What is Silica

Is a material found in magma that forms from the elements oxygen and silicon.

What is an Active Volcano

Is one that is erupting or has shown signs that it may erupt in the near future.

How does water affect the rock structure

It allows the rock to melt.

What is Lava

Lava is magma when it reaches the surface.

What is Magma

Magma is a molten mixture of rock-forming substances, gases, and water from the mantle.

What is a Dike

Magma that forces itself across rock layers hardens.

What is a Still

Magma that squeezes between horizontal rock layers hardens.

What is Subduction

Subduction is when the less dense plate floats on top of the more dense plate.

Which island of Hawaii is an active volcano

The Big Island

As magma rises toward the surface, what happens to the gases in it

The gases expand because of the decrease in pressure.

What does the present of hornblende minerals mean to geologists

The minerals form in water.

How does an explosive eruption produce pyroclastic flow

The movement of material. And they build up and explode.

What is an Island Arc

The resulting volcanoes sometimes create a string of islands.

What would happen if water was absent from the rocks

The volcanoes would have not formed.

what landforms Do Lava And Ash Create

These landforms include shield volcanoes, cinder cone volcanoes, composite volcanoes, and lava plateaus.

What is a Shield Volcano

Thin layers of LAVA that pour out of a vent and harden on top of previous layers build a wide, gently sloping mountain.

Has the Pacific Plate changed direction in the last 30mya

Trueee

Where does a Volcano form

Volcanoes form above a hot spot when magma erupts through the crust and reaches the surface.

How does a volcano erupt

When a volcano erupts, the force of the expanding gases pushes magma from the magma chamber through the pipe until it flows or explodes out of the vent.

What is High-Vscosity

When magma is thick and flows slowly.

What is Low-Viscosity

When magma is thin and flows more quickly.

How do volcanoes change Earth's surface

When the explode of magma comes out and becomes lava when lava cools it forms a solid rock. And it creates new rock.

Why do some many of Earth's volcanoes occur along plate boundaries

When two plates pull apart they form volcanoes. Magma filling in cracks and gaps in the boundaries.

How do geologists classify volcanic eruptions as quiet or explosive

Whether an eruption is quiet or explosive depends in part on the magma's silica contents and whether the magma is thin and runny or thick and sticky.

What is the Ring of Fire

a major belt of volcanoes.

Why is carbon 12 important to geologists

carbon 12 comes from organisms that form in the ocean.

What is a vent

molten rock and gas leave the volcano through an opening.

What is Viscosity

Refers to a fluid's resistance to flow.

What is a Lava Plateau

Repeated floods of LAVA can form high, level plateaus.

How long is the "Ring of Fire"

25 thousand miles

What percentage of earthquakes and volcanoes are located around the "Ring of Fire"

75% Volcanoes 90% Earthquakes

who many islands make up The Hawaiian Islands

8 Islands

What is a Volcanic Belt

A Volcanic Belt forms along the boundaries of Earth's plates.

What is a Crater

A bowl-shaped area that may form at the top of a volcano around the central vent.

What year did Mount Saint Helen erupt

May 1980

What is an Extinct Volcano

Or dead, volcano is a volcano that is unlikely to ever erupt again.

What is a dormant Volcano

Or sleeping, volcano is a volcano that scientists expect to awaken in the future and become active.

How do landforms form magma form and become exposed

Over time, forces such as flowing water, ice, or wind may strip away the layers above the hardened magma and expose it.


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