Volcanic Eruption

By:- Parghi Gautam

OUTLINE :-

Introduction

Process of volcanic eruption

Types of volcanic eruption

Reasons of volcanic eruption

Effect of volcanic eruption

Safety tips

INTRODUCTION

A volcano is a mountain where lava (hot, liquid rock) comes from a magma chamber under the ground.

Most volcanoes have a volcanic crater at the top.

When a volcano is active, materials come out of it. The materials include lava, steam, gaseous sulphur

compounds, ash and broken rock pieces.

Worldwide, 50 to 60 volcanoes erupt each year.

PROCESS OF ERUPTION Volcanic activity, or volcanism, is directly related to

plate tectonics, and most active volcanoes are located near plate boundaries.

As spreading or sinking lithospheric plates interact with other Earth materials, magma, or molten rock, including a small component of dissolved gases, mostly water vapor and carbon dioxide, is produced.

Magma that has emerged from a volcano onto Earth’s surface is called lava.

Approximately two-thirds of all active volcanoes on Earth are located in the “ring of fire”.

TYPES OF VOLCANIC ERUPTION

Cylinder cone

Shield Volcanoes

Composite Cones or Stratovolcanoes

Lava Dome

REASONS OF VOLCANIC ERUPTION

1) Due to Density-difference in Magma

2) Pressure of Released Gases

3) Injection of New Magma

DUE TO DENSITY-DIFFERENCE IN MAGMA

PRESSURE OF RELEASED GASES

INJECTION OF NEW MAGMA

EFFECTS OF VOLCANIC ERUPTION

SAFETY TIPS As much as possible, stay away from active

volcanoes.  If you live near an active volcano, keep

goggles and a mask in an emergency kit, along with a flashlight and a working, battery-operated radio.

Know your evacuation route. Keep gas in your car.

IF A VOLCANO ERUPTS IN YOUR AREA Evacuate only as recommended by authorities to

stay clear of lava, mud flows, and flying rocks and debris.

Avoid river areas and low-lying regions. Before you leave the house, change into long-

sleeved shirts and long pants and use goggles or eyeglasses, not contacts. Wear an emergency mask or hold a damp cloth over your face.

If you are not evacuating, close windows and doors and block chimneys and other vents, to prevent ash from coming into the house.

Be aware that ash may put excess weight on your roof and need to be swept away. Wear protection during cleanups.

REFERENCE http://www.nationalgeographic.com/environm

ent/natural-disasters/volcano-safety-tips/

Introduction to Environmental Geology Edward keller

K. S. Valdiya, Environmental Geology: Indian Context

Thank you