Home » » When Java and Sumatra Separate

When Java and Sumatra Separate

Written By Kepri Online on Tuesday, November 29, 2011 | 19:58

Experts have agreed that the island of Java to Sumatra had fused. Together Borneo, then form a plateau called the Great Sunda. The separation of Java and Sumatra are the result of plate movements are believed to Earth, though not a few who argued that the eruption of Mount Krakatoa as the cause of this separation.

Arguments supporting the separation of Java and Sumatra since the eruption of Krakatoa usually refers to the Library Raja Purwa, written by poet Java, Ronggowarsito, in 1869. In this book narrated, the eruption of Mount Kapi-later identified as Mount Krakatoa-the cause of the separation of Java and Sumatra. This incident mentioned occurred in the year 416 AD.

Photo : kompas.com

Researcher from Los Alamos National Laboratory (New Mexico), Ken Wohletz, including the support of the possibility of a major eruption of Krakatoa primordial to separate the island of Java and Sumatra. He made a simulation of super-eruption scenario. However, in contrast to Ronggowarsito, Ken said, the eruption was the possibility of tens of thousands of years ago.

Through carbon dating and radioactive, geologists ensure that Krakatoa erupted had some great times. "It seems that the formation of the Sunda Strait is not possible because a single large eruption, as written in the legend (Library Kings) it. At least two major periods in the Krakatoa eruption, but that's about hundreds or even thousands of years ago, not in the year 416 AD," said Zeilinga de Boer and Donald Theodore Volcanoes in Human Sannders in History, 2002.

Although the recording time Ronggowarsito about past eruptions of Krakatoa doubt its accuracy, these poets probably right about "separation" Java and Sumatra are strongly associated with the eruption of Krakatoa. However, the separation of Java and Sumatra likely not due to the eruption of Krakatoa. Conversely, Krakatau formed by splitting the two islands as a product of tectonic movements in the Earth.

Geologists from the Geological Museum, Indyo Pratomo, say, the separation of Java and Sumatra due to tectonic movements. "The island of Java and Sumatra, moving with different speeds and directions due to the Indo-Australian plate collision to the Euro-Asia. This difference causes the opening of a crack in the Earth, "says Indyo.

As Indyo, The Center for Volcanology and Geological Hazard Mitigation (PVMBG) Surono also believes that the tectonic process forming Krakatoa. The island of Java, according to Surono, moving eastward with a speed of about 5 centimeters (cm) per year, while the island of Sumatra, moving toward the northeast at 7 cm per year. This process causes the island of Sumatra moved to the north and left the island of Java, thus opening up the Earth's crust in the Sunda Strait.

So far, Sumatra has been spun about 40 degrees compared to Java. Jelle Zeilinga and Donald Theodore mentions, half of this cycle occurs in two million years. This rotation causes the stretching between the two islands, a way for the melted rock, or magma, to exit along the fracture zone Krakatau, thus forming the body of the mountain from the sea floor.

Distribution of energy

Surono said, volcanic eruptions occur principally as a form of energy from below the Earth collected by the Earth's plate movements. Apart from a volcanic eruption, this energy can also be released in the form of earthquakes.

"The eruption of volcanoes and earthquakes are usually co-exist," he said. In Sumatra, the energy of plate movements more channeled in the form of high intensity earthquakes along the Great Sumatran Fault. "This condition causes no longer exists in Sumatra eruption a large-scale fire."

Toba Supervolcano eruption that changed the Earth, the last occurred about 74,000 years ago. "At that time, perhaps a large Sumatran fault condition is not as active now so that the accumulated energy is released in the form of the Toba volcanic eruption," said Surono.

By contrast, in Java, the intensity of earthquake ground is relatively small compared to Sumatra. However, the eruption of the fire is relatively more frequent. "Energy is collected from plate collision mostly distributed in the form of volcanic eruption due to ground fault in Java nothing major," he said.

What about Krakatoa located between two geological systems of Java and Sumatra, this different?

Krakatau is located at the hinge point between Java and Sumatra to be unique. Coupled with the existence of the ocean that surrounds this volcanic island, Krakatoa became very dangerous. In the event of leakage and sea water penetrates into the Earth to near the boiling magma pockets, a large eruption could occur. In fact, if there is a large eruption, the possibility of a tsunami is also very high.

The re-emergence of Anak Krakatau from the sea in the 1930s, after a major eruption in August 1883 and destroyed almost the entire body of this volcanic island, indicating that supply magma tectonic activity continues to occur. Will Anak Krakatau to be like "mother" that erupted great, sent a giant tsunami that killed more than 36,000 lives?

Geologist and author of popular books, Simon Winchester (2003), mentions, the processes that lead to the disastrous events of 1883 can not be stopped. During the process of plate subduction or subduction still occurs, so long energy supply and magma to Krakatoa will continue to accumulate.

The problem is, we will never know when and how strong the volcano will erupt. "If there is a tool that can predict volcanic eruptions would I buy all. Including the seller," Surono joked. "We can not fight nature. However, you can do is how we build a strong system of disaster mitigation and prepare people to continue to be vigilant," he continued.
souce: kompas.com
Share this article :

0 comment:

Post a Comment

Support : Creating Website | Johny Template | Mas Template
Copyright © 2011. Kepri Online - All Rights Reserved
Template Modify by Creating Website
Proudly powered by Blogger