Volcanoes part 2

A _________________ is a giant crack in Earth's surface. Eruptions from these cracks can result in the formation of ________________________, which are thick, mostly flattened layers of cooled lava. Sometimes, magma below a __________ or the opening at the tope of a volcano, empties out of a magma chamber. This loss of internal support can cause the roof of the magma chamber to collapse, leaving a larger hole, called a __________.

1. Fissure 2. Lava Plateaus 3. Crater 4. Caldera.

Is a volcano that is in the process of erupting or shows signs that it may erupt at some point in the future.

Active or Live Volcano

This volcano has a broad base and gently sloping sides. It was formed from quiet eruptions. This volcano is a shield volcano.

Alcedo Volcano

Is a mass of rock that forms when a large body of magma cools inside the crust. This forms the interiors of many mountains and are usually very large. For example, the Sierra Nevada thing forms the core of the Sierra Nevada mountain range in California. Erosion exposes this. This in the Sierra Nevada thing is visible due to erosion.

Batholith

Is a large, basin-shaped depression in Earth's surface.

Caldera

Forms when ash and pieces of lava are thrust into the air during an explosive eruption. These fragments fall around a small vent, forming steep sides and a bowl-shaped crater.

Cinder Cone Volcano

Is a steep, cone-shaped hill or small mountain.

Cinder Cone Volcano

Forms from alternating layers of hardened lava flows and pyroclastic material. These volcanoes most commonly develop into steep large volcanic mountains.

Composite Volcano

Is also known as a stratovolcano. It is a cone-shaped volcano that is created by a buildup of layers of lava and ash.

Composite Volcano

Is a large bowl-shaped landform that may form at the top of a volcano.

Crater

Forms when magma forces itself across older layers of rocks and hardens.

Dike

Forms when hardened magma pushed upward and forces layers of rock to bend into a dome shape.

Dome Mountain

Also known as a sleeping volcano. It is a type of active volcano that doesn't erupt, but can erupt again sometime in the future.

Dormant Volcano

This thrust lava into the air, they can create a dangerous mixture of materials called a pyroclastic flow.

Explosive Eruptions/Volcanoes

Also known as a dead volcano. It is a type of volcano that is never going to erupt again.

Extinct Volcano

Is a giant crack in the Earth's surface.

Fissure

This occurs when there is no central opening for an eruption in which the lava flows out of an entire fissure.

Fissure Eruption

Is a thick, mostly flattened layer of cooled lava.

Lava Plateau

It is Hawaii's tallest volcano. Its last eruption was between 6,000 and 4,000 years ago. This volcano could erupt again, making it an dormant volcano.

Mauna Kea

Material ejected from a volcano can build up around the vent and create volcanic mountains. For example, this volcano is tall and cone-shaped. It was formed from alternating layers of hardened lava and pyroclastic material. This volcano is a composite volcano.

Mount Cayley

Is a volcano in Italy. It erupted in 2014 and it has had many eruptions in the past 100 years. This volcano is an active volcano.

Mount Etna

It is a volcano in Tanzania, Africa. Its last major eruption was about 100,000 years ago, and it is not expected to erupt again. This volcano is an extinct volcano.

Mount Kilimanjaro

Is a steep, cone-shaped hill. It was formed from an explosive eruption, from which ash and cinders built up around the vent. This volcano is a cinder cone volcano.

Prindle Volcano

Is a dense, destructive mixture of hot gases, ash cinders, and bombs that is ejected from a volcano that erupts explosively. As it pours down the volcano's sides, this flow can sometimes cause landslides of mud, melted snow, rocks, and trees.

Pyroclastic Flow

Often eject lava. When this lava flow, it can often set fire to whatever it encounters and can bury everything in its path. The lava flow can cover large areas with a thick layer of lava.

Quiet Eruptions

Has a broad base and gently sloping sides. It generally forms from quiet eruptions as layers of lava flow out, harden and slowly build up.

Shield Volcano

Is a wide, dome-shaped volcano with gently sloping sides.

Shield Volcano

Forms when magma that squeezes between horizontal rock layers hardens.

Sill

Scientists use instruments to try to predict future eruptions. What are scientists looking for to determine future eruptions?

The changes in activity inside a volcano and around a volcano.

Which factors affect whether a volcano will erupt quietly or explosively

The magma's viscosity and the magma's gas content.

Which of the following is being shown by the following steps below A. Magma rises when it is less dense than the surrounding rock. B. As the magma rises, the pressure decreases and gases in the magma form bubbles in the magma. C. Expanding gases push magma from the chamber through the pipe, but cannot escape past the thick magma. D. The gases continue to expand, exploding magma out of the volcano.

The steps of how an explosive eruption occurs.

How do Composite Volcanoes form

They form from both quiet and explosive eruptions.

How do Cinder Cone Volcanos form

They form from explosive eruptions.

How do Shield Volcanos form

They form from quiet eruptions

During an explosive eruption, lava is thrust into the air. The lava breaks into fragments that quickly cool and harden. This results in fragments the size of dust called volcanic ash, pebble-sized fragments called cinders, and larger fragments, at least 6.4 in diameter, called bombs.

True

The lava and ash from eruptions can cool and build up around the vent, forming mountains. Magma's viscosity determines the type of eruption of a volcano while lava's viscosity determines the shape of the forming mountain.

True

Forms when magma hardens within a vent on an active volcano, and the surrounding rock layer wears away.

Volcanic Neck

How does a caldera form

When a crater from a volcano collapses.