From UPSC perspective, the following things are important :
Prelims level : Taal Volcano
Mains level : Volcanism and its impact
In the Philippines, a volcano called Taal on the island of Luzon; 50 km from Manila has recently erupted.
- Taal is classified as a “complex” volcano. Taal has 47 craters and four maars (a broad shallow crater).
- It is situated at the boundaries of two tectonic plates — the Philippines Sea Plate and the Eurasian plate — it is particularly susceptible to earthquakes and volcanism.
- A complex volcano, also called a compound volcano, is defined as one that consists of a complex of two or more vents, or a volcano that has an associated volcanic dome, either in its crater or on its flanks.
- Examples include Vesuvius, besides Taal.
- The Taal volcano does not rise from the ground as a distinct, singular dome but consists of multiple stratovolcanoes (volcanoes susceptible to explosive eruptions), conical hills and craters of all shapes and sizes.
- Taal’s closeness to Manila puts lives at stake. Manila is a few tens of kilometres away with a population of over 10 million.
- The volcano is currently at alert level 4, which means that a “hazardous eruption” could be imminent within a few hours to a few days.
- Hazardous eruptions are characterised by intense unrest, continuing seismic swarms and low-frequency earthquakes.
Earlier records of eruption
- Taal has erupted more than 30 times in the last few centuries. Its last eruption was on October 3, 1977.
- An eruption in 1965 was considered particularly catastrophic, marked by the falling of rock fragments and ashfall.
- Before that, there was a “very violent” eruption in 1911 from the main crater. The 1911 eruption lasted for three days, while one in 1754 lasted for seven months.
- Because it is a complex volcano with various features, the kinds of eruption too have been varied. An eruption can send lava flowing through the ground, or cause a threat through ash in the air.