Everything we know about the past is changing. A meeting held back in June known as the ICS announced a literal new division in time.

This new division will now appear on all official charts depicting Earth’s geological past and breaks things down much more. For those who do not know, the ICS is the International Commission on Stratigraphy, it covers so much more than you’d think. Now, the International Chronostratigraphic Chart that shows our planet’s past is a lot more in-depth than you’d think. It is used to show the divisions of the planet’s history which covers almost 5 billion years.

These different ages are separated by things like major events (continent breakage, climate changes, and other things of the sort). The Meghalayan age was something proposed around seven years ago because of chemical signatures found in rock (stalactites and stalagmites). This new chapter covers the last 4,200 years.

BBC reported as follows in regards:

To win a classification, 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.

For the famous boundary 66 million years ago that marks the switch in period from the Cretaceous to the Palaeogene, this “golden spike” is represented by traces in sediments of the element iridium. This was spread across the planet in the debris scattered by the asteroid that wiped out the dinosaurs.

For the Meghalayan, the spike is epitomized in a perturbation in the types, or isotopes, of oxygen atoms present in the layers of a stalagmite growing from the floor of Mawmluh Cave in the northeastern state of Meghalaya in India. This two-step change is a consequence of weakening monsoon conditions.

“The isotopic shift reflects a 20-30% decrease in monsoon rainfall,” explained Prof Mike Walker of the University of Wales, UK, who led the international team of Holocene scientists that developed the division proposal.

“The two most prominent shifts occur at about 4,300 and about 4,100 years before present, so the mid-point between the two would be 4,200 years before present, and this is the age that we attribute to the [Meghalayan golden spike],” he told BBC News.

While I know this might sound a bit confusing it is quite amazing and really makes a huge difference in how we look at our world. What do you think about all of this?


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