The world may be entering the "plastic age", a leading academic has warned.
Professor Dan Parsons, a geologist, said that plastic waste is now so widespread that it will create a new layer in the Earth's crust.
Many scientists already believe that Earth has entered a new geological era - leaving the Holocene era and entering the Anthropocene era - because of the impact humans have had on the rocks that make up the surface of the Earth.
The start of the new era was determined based on when radioactive isotopes start to be detected in the geological record, due to the fall-out from atomic bombs.
But Parsons said plastic was now also leaving an indelible trace.
"As we move from the Holocene to what is now termed the Anthropocene, what's the imprint of humanity on the geological record of Earth?" asked Parsons, professor of sedimentology at Hull University.
"So if we fast forward 10 million years from now and we look back in the strata of the rocks, we will see a peak in radioactive isotopes from nuclear testing and we will see a load of plastics mineralised into the rock record.
"That's going to be our legacy in future when geologists 10 million years from now are looking back on us as a society, so there are some profound things to think about in terms of us and our record of looking after the world."
The term "Anthropocene" was first coined by Nobel Prize-winning chemist Paul Crutzen who in 2000 suggested that man's impact on the world was so substantial that we were no longer in the Holocene - the era which began at the end of the last Ice Age around 11,700 years ago and saw unprecedented human expansion.
Many scientists believe the world entered a new epoch on July 16, 1945, when the first atomic bomb was detonated in the New Mexico desert. The blast scattered radioactive particles from the poles to the equator, leaving an indelible signal in the surface strata of the Earth.
But in recent years plastic has been found in every ocean in the world, with 90 per cent falling to the sea bed where, according to experts, it will eventually be mineralised. It is estimated that by 2050 the weight of plastic in the world's oceans will be greater than marine life.
"In the same way as you preserve a fossil from the age of the dinosaurs ... bits of plastic can absolutely be incorporated into the geological record that is forming right now, and they can be mineralised and lithified in the same way as other lifeforms," said Parsons.
"Many people are now advocating that we're living in the Anthropocene and what do you use as that marker horizon - is it isotopes from nuclear tests that you see in the rock record of the future or is it the mineral deposits from a set of plastics?
"Some are arguing that it is actually the plastic horizon that will be the most distinguishable in terms of that rock record of the future."