Ancient ‘lost continent’ found lurking under the Island of Mauritius
The existence of a lost continent under the Indian Ocean island of Mauritius was confirmed by scientists. It is a left-over from the break-up of the supercontinent Gondwana, which started about 200 million years ago.
Volcanic eruptions on the island subsequently covered the crust with lava. It broke off from the island of Madagascar when Africa, India, Australia and Antarctica split up.
What led to the discovery:
- The mineral zircon was found in rocks spewed up by lava during volcanic eruptions
- The remnants of this mineral were far too old to belong on the island of Mauritius
- Earth is made up of two parts, continents, which are old and oceans which are young.
- Continents comprise of rocks that are over four billion years old, but you find nothing like that in the oceans
- Mauritius is an island and there is no rock older than nine million years old on the island. • However, study of the rocks on the island found zircons that are as old as three billion years
Significance of the discovery:
- It will help scientists study the break-up process of the continents, to understand the geological history of the planet
What are Zircons:
- Zircons are minerals that occur mainly in granites from continents
- They contain trace amounts of uranium, thorium and lead and since they survive geological process very well, they contain a rich record of geological processes that can be dated extremely accurately
Why did the study receive criticism earlier:
- Traces of the mineral in beach sand were found earlier. This was criticised as the mineral could have been either blown in by the wind, or carried in on by vehicle tires or shoes of scientists
- The discovery of ancient zircons corroborates the previous study and refutes the criticism of wind-blown, wave-transported or pumice-rafted zircons