Mt. Krakatoa

In Glogpedia

by s4twz6r
Last updated 6 years ago

Discipline:
Science
Subject:
Geostudies
Grade:
7

Toggle fullscreen Print glog
Mt. Krakatoa

-Mt. Krakatoa-

Location

Boundary and Crusts

The loudest volcanic eruption is history was produced by Mt. Krakatoa (10). Mt. Krakatoa was considered to be a stratovolcano; a tall, cone shaped volcano, that has steep sides and erupts frequently and violently. Another example of a stratovolcano would be Mount St. Helens. A volcano's magnitude is explained by the type of lava spewed by a volcano; the most explosive eruptions are caused by lava composed of dacite or rhyolite. These rocks are cooler and thicker allowing them to accumulate pressure before an eruption. Mt. Krakatoa erupted in 1833 and had lava composed of dacite and rhyolite. The eruption created a sound large enough to be heard across all of the surrounding islands. This served as a warning sign for the islands' inhabitants.

The Eurasian plate is comprised of oceanic and continental crusts (6). As the Indo-Australian plate moves northeastward it collides with the Eurasian plate, creating a convergent boundary (4). As it collides oceanic crust from the Indo-Australian plate is pushed under the continental crust of the Eurasian plate. This creates a subduction zone. From the subduction zone comes an underwater volcanic arc. The volcanos create islands after they erupt, such as the island of Krakatoa. Krakatoa was created by three volcanoes; including Mt. Rakata, Mt. Danan and Mt. Perboewatan. Mt. Krakatoa was just one of many volcanoes found in Indonesia. Indonesia holds the record for the largest amount of volcanos found in one nation; the total number is about 130 (3).

Volcanic Activity

Mt. Krakatoa used to be a volcano found on a deserted island, off the coast of the island of Sumatra (2). The island belonged to the nation of Indonesia (3). It was a part of the large horse-shoe shaped area surrounding the Pacific Ocean, called The Ring of Fire. The Ring of Fire is a violent area that witnesses many earthquakes, tsunamis, and volcanic eruptions each year (5). Mt. Krakatoa belonged to the Eurasian plate, which borders the Philippine plate, Pacific plate, and Indo-Australian plate.

1

2

3

4

5

6

7

8

9

10

It produced tsunamis with waves reaching 40 meters high, or 131 feet high (7). The waves even reached the tip of the Arabian Peninsula, some 7,000 kilometers away. The tsunamis alone killed 36,000 people and destroyed 165 coastal villages in Java and Sumatra.The eruption lasted two days; August 26 to August 27. This was enough time to release massive amounts of sulfur dioxide into the atmosphere. The sulfur mixed with the water vapor in the atmosphere to produce acid rain, and created an atmospheric shield that reflected sunlight; causing global temperatures to become lower by 1.2 degrees Celsius, or 34 degrees Fahrenheit. Global climates became erratic in the years that followed. The sky became an array of colors in which exotic rays illuminated the sky and produced halos around the sun and moon. The interesting lights inspired painters, such as William Ascroft in his, "Banks of the River Thames" (9). The global climate eventually stabilized four years later.

Mt. Krakatoa's eruption in 1883 destroyed over 60% of the island itself (1). The volcano disappeared along with the island under the ocean waves. Years later a submarine eruption created a new island and volcano. It was named Anak Krakatoa, meaning "Child of Krakatoa" in the Indonesian language. Anak Krakatoa has a radius of two kilometers and a height of 300 meters above sea level, yet it is not done growing. The volcano is growing at a rate of 5 meters per year. Its most recent eruption took place in 2009 (8).

Birth of A New Volcano


Comments

    There are no comments for this Glog.