CAPSULE 2VOLCANO

Direction for Computer Assisted lesson

Follow the Instruction given below:

This lesson is about the topic- VOLCANO.

This capsule contain suitable slides related to the concept.

Necessary Pictures are provided in each slide.

Use mouse (single click) to move to the next slide.

Click on the textbox to get the response.

Please note the direction given by the computer.

Brain Teasers are provided for developing concepts

Brain relaxers are provided for self checking with necessary explanation.

After completing the lesson the learners can recapitulate the lesson

through Test Your knowledge session.

A volcano is a rupture on the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface

Let us observe the picture and identify the factors involved in the creation of volcano…

Picture of factors causing volcanoLook at fig1 in which different factors are involved in the creation of volcano. Volcanoes are caused by multiple factors. from the figure identify the various factors involved in the creation of volcano

Fig.5

1 2

Spreading plate margin,subducting plate margin etc are the causes for volcano….

DEFINING THE TERM – VOLCANO

A volcano is a rupture on the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface

A volcano is a mountain that opens downward to a pool of molten rock below the surface of the earth. When pressure builds up, eruptions occur. Gases and rock shoot up through the opening and spill over or fill the air with lava fragments.

D4

Brain Teaser 2.1 volcanic ash can be a threat to aircraft

No Yes

Refer Brain Relaxer 2.1 Click here

Earth's volcanoes occur because its crust is broken into 17 major, rigid tectonic plates that float on a hotter, softer layer in its mantle. Therefore, on Earth, volcanoes are generally found where tectonic plates are diverging or converging

Here is the story of a volcanoHi , I am a silent conical mountain to look at ,but my interior is full of lava and poisonous gases that exert pressure on me to come out of it. I remain dormant for years .But when it becomes very difficult to suppress my inner pressure all on a sudden it comes out and creates volcanic eruption which results in many hazards. I feel very sorry for the whole incident but for my inner pressure to come out and feel relieved .

Here

is my

story

Clearly read the story and think for a while

Find out the different steps involved in the occurrence of volcanic eruptionHere are some pictures of volcanic eruption. Observe the picture and identify the different types of volcanic eruption

Here are some pictures of a cotton Industry. Observe the picture and identify the respective roles in the production process.

Fig.2

2

3

456

1

Types Definition

Stratovolcanoes Stratovolcanoes or composite volcanoes are tall conical mountains composed of lava flows and other ejects in alternate layers, the strata that give rise to the name

Super volcanoes A super volcano usually has a large caldera and can produce devastation on an enormous, sometimes continental, scale.

Submarine volcanoes

Submarine volcanoes are common features of the ocean floor. In shallow water, active volcanoes disclose their presence by blasting steam and rocky debris high above the ocean's surface. In

Subglacial volcanoes

Subglacial volcanoes develop underneath icecaps. They are made up of flat lava which flows at the top of extensive pillow lavas and palagonite. When the icecap melts, the lava on top collapses, leaving a flat-topped mountain

Mud volcanoes Mud volcanoes or mud domes are formations created by geo-excreted liquids and gases, although there are several processes which may cause such activity. The largest structures are 10 kilometers in diameter and reach 700 meters high.

ENLARGING THE DEFINITION

A volcano is a rupture on the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. Earth's volcanoes occur because its crust is broken into 17 major, rigid tectonic plates that float on a hotter, softer layer in its mantle.

Volcanic ash consists of powder-size to sand-size particles of igneous rock material that have been blown into the air by an erupting volcano

D5

Brain Teaser 2.2Throughout recorded history, ash produced by the explosive eruption of stratovolcanoes has posed the greatest volcanic hazard to civilizations.

No Yes

Refer Brain Relaxer 2.2

Click here

The most common perception of a volcano is of a conical mountain

DEFINITION

The most common perception of a volcano is of a conical mountain, spewing lava and poisonous gases from a crater at its summit; however, this describes just one of the many types of volcano. The features of volcanoes are much more complicated and their structure and behavior depends on a number of factors

D6

CONCEPT FORMATION

C2 Volcanic fissure vents are flat, linear fractures through which lava emerges.

UNIT 2

VOLCANOS

THINKING SESSION

Brain Relaxer 2.1

Ash plumes reached a height of 19 kilometers (12 mi) during the climactic explosive eruption at Mount Pinatubo, Philippines in 1991.

Cleveland Volcano is in the Aleutian Islands of Alaska

Barren Island, Andaman Islands, India, which erupted in 1995. is the only active volcano in South Asia.

The word volcano is derived from the name of Vulcano, a volcanic island in the Aeolian Islands of Italy whose name in turn originates from Vulcan, the name of a god of fire in Roman mythology.The study of volcanoes is called volcanology, sometimes spelled vulcanology.

Brain Relaxer 2.2

Look at the Fig. 3

Fig.3

VOLCANO ERUPTING

The number of people emloed can

be changed by introducing

machines. But this may lead to labour

unrest in most of the situations

Test your knowledge

Say True or False

1-The word volcano is derived from the name of Vulcano

2-The most common perception of a volcano is of a conical mountain

Answer---

True False

True False