THE asteroid that caused the extinction of the dinosaurs 66 million years ago left sediments of metal iridium around the world, which marked the end of the Cretaceous Epoch.
Following the ice age, Earth was shifted into a new epoch known as the Holocene era and it has remained there ever since.
However, the rapid industrialisation of our planet over the last century has had such a profound impact that a new geological era needs to be declared.
This is the belief of an international team of researchers speaking at the International Geological Congress on Monday.
The researchers suggested we have entered human-influenced age known as the Anthropocene Epoch, which would be the first new geological epoch in more than 11,700 years.
The Working Group on the Anthropocene believe it should begin at 1950 to coincide with the nuclear bomb tests that created new and distinctive strata — layer of the Earth.
Of the 35 scientists involved in the group, 30 voted in favour of formally declaring a new geological era, three disagreed and two were absent.
Principal geologist at the British Geological Survey and WGA secretary Colin Waters said the vote was a scientific endorsement that the epoch is geologically real.
“Being able to pinpoint an interval of time is saying something about how we have had an incredible impact on the environment of our planet,” he said, reported The Telegraph.
“The concept of the Anthropocene manages to pull all these ideas of environmental change together.”
Geologist and chair of the WGA Jan Zalasiewicz said the Anthropocene Epoch illustrated the “great acceleration” of the 20th century which saw a distinct change in the carbon and nitrogen levels in the atmosphere.
“Human action has certainly left traces on the earth for thousands of years, if you know where to look,” he said.
“The difference between that and what has happened in the last century or so is that the impact is global and taking place at pretty much the same time across the whole Earth.
“It is affecting the functioning of the whole earth system.”
The working group will now spend the next three years attempting to pinpoint a “golden spike” to define the beginning of the Anthropocene Epoch.
As the end of the Cretaceous Epoch was marked by sediments of metal iridium from the asteroid that killed the dinosaurs, researchers will need to find something equally as drastic.
Mr Zalasiewicz said the best candidate for the “golden spike” for the new geological era was the radioactive elements from nuclear bomb tests.
“The radionuclides are probably the sharpest — they really come on with a bang,” he said.
“But we are spoiled for choice. There are so many signals.”
Other spikes being considered as evidence are carbon dioxide emissions, rising sea levels, the mass extinction of species, the worldwide spread of plastics, concrete and the transformation of land by deforestation are other contributing factors.
Mr Zalasiewicz said despite sounding promising, the declaration of the Anthropocene is not yet official.
“Our stratigraphic colleagues are very protective of the geological time scale. They see it very rightly as the backbone of geology and they do not amend it lightly,” he said.
“But I think we can prepare a pretty good case.”
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