The recent eruption of the Semeru volcano in Indonesia has made international headlines, raising questions about this geological marvel. Known as “The Great Mountain”, Semeru is not only the highest volcano on Java Island, but it’s also one of the most active. This island nation, located on the Pacific’s Ring of Fire, holds the record for the highest number of active volcanoes globally.
Understanding Semeru Volcano and its Geographic Relevance
Semeru is part of a larger geological formation known as the Island arcs, caused by the subduction of the Indo-Australian plate beneath the Sunda Plate, itself a part of the larger Eurasian Plate. Consequently, a trench, referred to as the Sunda trench, has formed, with the Java Trench making up its major section. Being situated in such volatile surroundings, seismic activities are fairly common in this area.
Insights Into the Pacific Ring of Fire
The Pacific Ring of Fire, otherwise known as the Circum-Pacific Belt, is infamous for frequent earthquakes and active volcanoes. It serves as the boundary line for several tectonic plates, namely the Pacific, Cocos, Indian-Australian, Nazca, North American, and Philippine Plates. The Ring of Fire has been a significant area of study for geologists due to its high seismic and volcanic activity.
Exploring the Concept of Island Arcs
Island Arcs represent long, curved chains of oceanic islands linked with intense volcanic and seismic activities, leading to the process of mountain-building or orogenic processes. Owing to the arc’s structure, one side usually features a land mass or a partially enclosed, unusually shallow sea. Conversely, the other side invariably houses a deep-sea trench showcasing unimaginable ocean depths. Examples of this natural spectacle include the Mariana and Tonga trenches, Aleutian-Alaska Arc, and the Kuril-Kamchatka Arc.
Recent Global Volcanic Activities
The world has also recently witnessed the eruption of other volcanoes like Ecuador’s Sangay Volcano, Philippines’ Taal Volcano and Indonesia’s own Mt. Sinabung and Merapi volcano. India, on the other hand, houses the nation’s only active volcano, the Barren Island, located in the Andaman Islands.
India’s Volcanic Landscape
In addition to the Barren Island, other geological formations in India with volcanic history include Narcondam and Baratang in the Andaman Islands, Deccan Traps in Maharashtra, and Dhinodhar Hills and Dhosi Hill in Gujarat.
Important Facts for the UPSC Civil Services Exam
For those preparing for the UPSC Civil Services Examination, it is crucial to remember that the Barren Island is India’s only active volcano, located about 140 km from Port Blair, the southern part of the Andaman Island. In the last century, it erupted at least five times, most notably in 1991. Since then, eruptions were reported approximately every two to three years, with the latest occurrence noted in February 2016.
Further Study Points
For a comprehensive understanding of the subject matter, one could delve deeper into the geophysical characteristics of the Circum-Pacific Zone. Another topic of interest lies in examining the global occurrence of volcanic eruptions in 2021 and their impact on regional environment.