Example of Ash and Cinder volcano; Paricutin, Mexico

PARICUTIN: The volcano born in a Mexico cornfield



History:
- The Paricutin eruption took place between February 1943 and February 1952.
- The Paricutin volcano grew out of a cornfield.
- The worst of Paricutin's volcanic activity, took place in 1943, with its lava rising to about 50 feet below the crater's rim.
- The Paricutin volcano now stands at exactly 1,345 feet above the ground and 9,210 feet above sea level.
- It hardened lava is covers about 10 square miles, its volcanic sand (unconsolidated fragments of volcanic material) covers about 20 square miles
- The type of eruption which happened at Paricutin is called a Strombolian eruption, which means it gushed basaltic lava, and exploded from a single vent.
- Nearly 1000 people died following one of its last major eruptions in 1949.
- Paricutin is situated about 200 miles west of Mexico City, in the state of Michoacán, Mexico.
- Ashes from the volcano fell as far as Mexico City.
- The Paricutin is part of the Volcanic Axis, a.k.a., "The Transversal", a 700 mile line of volcanoes that extends across southern Mexico in an east-west direction.
- It is the only one of several hundred cones in the area to have erupted in historic times.
- The Paricutin is a Monogenetic cone, meaning it stems from a single point of eruption.
- The man who first Witnessed the eruption in 1943, was Dominic Pulido, a Tarascan Indian farmer.


Paricutin spewing ash

Example of Lava dome; Mount St. Helens, USA

Characteristics:
.Prior to 1980, Mount St. Helens formed a conical, youthful volcano sometimes known as the Fuji-san of America
.Prior to 2200 years ago, tephra, lava domes, and pyroclastic flows were erupted, forming the older St. Helens edifice, but few lava flows extended beyond the base of the volcano
.The modern edifice was constructed during the last 2200 years, when the volcano produced basaltic as well as andesitic and dacitic products from summit and flank vents.



Crater from Spirit Lake, tele photo lens, 1988: What appears like volcanic steam (right) is in fact dust caused by rockfalls on the inside of the crater wall. The lava dome (center) is, however steaming slightly



Tree trunk near Windy Ridge, 1988. Note how after only eight years flowers are growing already.

Credits:www.swisseduc.ch/stromboli/perm/msh/photo-en.html

OCTOBER 2004 DOME ERUPTION

Explaining different types of volcanoes through video

Credits: Youtube

current active volcanoes; Tungurahua, Ecuador

Tungurahua, Ecuador



Night view of one of many explosive events at Tungurahua Volcano, Ecuador, that occurred during the continuous extrusion of lava in the summit crater in November and December. In this time-lapse photograph, glowing lava fragments can be seen blasting into the air and falling onto the upper flanks of the volcano. Photo Credit: Alcinoe Calahorrano on November 2, 1999

Characteristics:
.Tungurahua is an active stratovolcano also known as the "The Black Giant."
.It is a steep-sided andesitic-dacitic stratovolcano that towers more than 3 km above its northern base, is one of Ecuador's most active volcanoes.
.They have been accompanied by strong explosions and sometimes by pyroclastic flows and lava flows that reached populated areas at the volcano's base.
.Tungurahua causes many tremors in the nearby city of Banos
.Tungurahua's lava is mostly composed of basalts.




Whats happening currently:
.Volcanic tremor and long-period earthquakes; On 24 February at 0310, tremor amplitude increased
.Incandescent material was ejected 800 m above the summit and fell on the flanks about 1 km below the summit.
.On 25 February, 12 moderate to large explosions occurred according to seismic interpretation
.On 26 February, a plume with no ash content rose to 6 km ;Later that day, two explosions produced ash plumes that 7 km ;
.On 27 February, incandescent material was ejected above the summit and fell on the flanks about 500 m down the flanks.
.Noises produced by material rolling down the flanks and "cannon shots" were heard during 25-27 February.


Credits: http://volcano.und.edu/vwdocs/current_volcs/tungurahua/tung.html

current active volcanoes: Kliuchevskoi, Kamchatka, Russia

Kliuchevskoi, Kamchatka, Russia

General Description :Kliuchevskoi is one of the most active volcanoes of the Kamchatka Peninsula in Far Eastern Russia.The volcano has had more than 80 eruptions since 1697.On September 15, 1994, gas and ash shot out of the crater, creating a column 2 km high. Over the next two weeks the eruption continued, and on 1 October a giant eruption occurred. A cloud of ash rose 15-20 km above the volcano. A picture taken by a weather satellite showed that the ash cloud extended 565 km to the SE, and that it was moving at about 140 km/hr (~85 mile/hr)! While ash was being blown out the top of the volcano, new rivers of lava flowed down its flanks. During the next three days the eruption stopped, and only steam rose above the crater.

effect: Because few people live near Kliuchevskoi there was little immediate danger, and most of the ash blew out to sea. However, Kamchatka is on a major airline route and at least one Boeing 747 Jumbo Jet had to fly higher to avoid ash layers at 9-11 km elevation. Aircraft that flew through ash clouds from eruptions of other volcanoes have had their engines clogged with ash and the planes nearly crashed.

Credit: http://volcano.und.edu/vwdocs/current_volcs/kliuchevskoi/kliuch/kliuchevskoi.html

Introduction to volcanoes

WHAT IS A VOLCANO
A volcano is a extrusive geological landform (usually a mountain) where magma (rock of the earth's interior made molten or liquid by high pressure and temperature) erupts through the surface of the planet. This phenomenon tends to occur near the boundaries of the continental plates. However, important exceptions exist in hotspot volcanoes.



WHAT ARE ITS FEATURES
It is generally a conical or dome shaped structure which is formed when magma escapes to the earth's surface as lava through an opening called a vent. At the top of most volcanoes is a deperssion which is called a crate. this is where gases, pyroclasts and lave are thrown out. An enlatged crater is called a caldera. The crater of a dormant or extinct volcano may contain a lake. The crater is joined by a central passageway, called a pipe to the ven. The magma that escapes through the vent comes from a magma chamber deep below. Some volcanoes have parasitic or secondary cones on its flanks.



HOW IS IT FORMED
Volcanoes are formed by rising magma from below the earth's crust. The magma which contains dissolved gases, such as carbon dioxide and sulphur dioxide are subject to great pressure under the earth. When there are breaks or fractures in the rocks, the magma moves into them. As it moves upwards, the pressure on it is greatly reduced. This allows the dissolved gases to expand and eject hot volcanic material through the vent to the earth's surface. The volcanic eruption piles up on the ground around the vent. The accumulation of the material, resuting from repeated eruptions, eventually builds up a volcano.



WHAT ARE THE TYPES OF VOLCANIC MATERIAL
When volcanoes erupt, the eject lava, gases and solid material.

LAVA: there are two types of lava - acid and basic lava.

Acid lava is produced when there is subduction at destructive plate boundaries. The subducting oveanic crust partly melts because of friction and hear and the magma produced, being less dense than the mantle, rises to the surface through lines of weakness.

-This acid lava is rich in silica.
-It is not as hot as basic lava
-It cools and solidifies quickly so it does no move very far
-It is viscous, so it moves very slowly
-It produces steep sided volcanoes (e.g. Mount pelee in the Caribbean island of Martinique)
-When viscous lava solidifies in the central pipe, it blocks the passageway. The build up of pressure by rising magma causes loud and violent explosions


Basic lava is produced at constructive plate boundaries beneath the oceans by the upward movement of magma from the mantle and above hot spots. This lava is rich in iron and magnesium. It has a lower silica content than acid lava.

-It is hot
-It is a fluid
-It flows for quite a distance before solidifying
-It forms gently sloping volcanoes that genetrally erupt quietly (e.g. Mauna Loa in Hawaii)


GASES:
Hot gases which are emitted during an eruption include steam, carbon dioxide and sulphur dioxide. The steam comes from heated underground water and surface water of crater lakes and the sea. It condenses to form clouds that bring rain.


SOLID MATERIALS:
The solid materials include ash, dust, cinders and volcanic bombs. They are collectively called pyroclasts.




photo of a volcano erupting lava as well as lava flowing down its flanks


MAKE YOUR OWN VOLCANO!
First, you need to make the model. You can make it out of clay, paper mache'; or plasticine. The items needed are:

Mix together:
1 small bottle
enough plasticine in a volcanic color: e.g. brown, red, pink etc.
2 table spoons of baking soda
enough vinegar
red food coloring
eno salts
water

Shape the plasticine around a small plastic bottle to make a mountain. The bottle acts as the chimney of the volcano.

You can add red food coloring to the vinergar to get a red eruption. With a funnel add 2 tablespoons of baking soda into the bottle. Then slowly add red vinegar to the bottle. The liquid will foam and flow down the sides of the mountain.

When you mix vinegar and baking soda together, it creates carbon dioxide. Carbon dioxide is the same gas that causes the lava to bubble and is produced during a volcanic eruption.

You can also repeat this with Eno and water. Add red food coloring to the water for the same desired lava color. Take some Eno salts and add it into the bottle. Pour the red water in.

This will give you a thicker flow than the baking soda and vinegar one.

You can then use it to compare between the different types of lava. Baking sode and vinegar as basic lava. And the more viscous Eno one as acid lava.

ENJOY! courtesy of HANNAH! : D