All about Meghalayan Age, the new phase in Earth's history
New Delhi : Talk about the different eras of Earth’s history and you will find so many ages as per the Geological Time Scale. Lately, the International Union of Geological Sciences (IUGS) tweeted the latest changes chronostratigraphic chart that highlights the ‘the Meghalayan Age’ as the newest phase of the lively planet.
Calculating the past 4,200 years as a diverse phase in the Earth’s geology, Geologists have defined the new Geological Time Scale as ‘the Meghalayan Age’ the onset of a period which is marked by a mega drought which put an end to many civilizations across the globe, including the popular Indus Civilization.
Geologists say that we currently live in the Holocene Epoch marked by various striking events which took place about 11,700 years ago. Even if the Meghalayan Age is the newest phase of the Holocene Epoch, there are other two sub-divisions called the Northgrippian and Greelandian which are the middle phase and oldest phase of the Holocene respectively.
While passing through the new geological time scale, Professor Stanley Finney,the Secretary-General of the IUGS said, “The Meghalayan Age is unique among the many intervals of the geologic timescale in that its beginning coincides with a global cultural event produced by a global climatic event”.
A key fact that is required to be passed in order to secure a classification is that ‘a slice of geological time generally has to reflect something whose effects were global in extent, and be associated with a rock or sediment type that is clear and unambiguous’. The Meghalayan Age is already proven have existed in all the seven continents.
Experts say that the rock records play an important role in classification of the geological time scale. In terms of history, the asteriod that led to the extinction of the dinosaurs about 66 million years ago left the traces of the element iridium scattered as sediments throughout the planet. This has been also considered as the period of transition from the Cretaceous Period to the Palaeogene.
Professor Mike Walker who led the international team of Holocene scientists that developed the division proposal said, “The Meghalayan Age’s timestamp is an isotopic shift found in a single stalagmite growing from the floor of the Mawmluh Cave in Meghalaya, India. The change in oxygen atom isotopes indicates the area experienced a 20 to 30 percent decrease in monsoon rainfall during the mega-drought that launched the new geologic age”.