A small lake near Milton, Ontario marks the official start of the Anthropocene Epoch

[TheVat]

https://apnews.com/article/humans-epcoch-anthropocene-climate-change-power-4699002bbc3b60ade715ee94a7b7567d

This puts the power of humans in a somewhat similar class with the meteorite that crashed into Earth 66 million years ago, killing off dinosaurs and starting the Cenozoic Era, or what is conversationally known as the age of mammals. But not quite. While that meteorite started a whole new era, the working group is proposing that humans only started a new epoch, which is a much smaller geologic time period.

The group aims to determine a specific start date of the Anthropocene by measuring plutonium levels at the bottom of Crawford Lake.

The idea of the Anthropocene was proposed at a science conference more than 20 years ago by the late Nobel Prize-winning chemist Paul Crutzen. Teams of scientists have debated the issue since then and finally set up the working group to study whether it was needed and, if so, when the epoch would start and where it would be commemorated.

Crawford Lake, which is 79 feet (29 meters) deep and 258,333 square feet (24,000 square meters) in area, was chosen over 11 other sites because the annual effects of human activity on the earth’s soil, atmosphere and biology are so clearly preserved in its layers of sediment. That includes everything from nuclear fallout to species-threatening pollution to steadily rising temperatures....

 

Seems tricky, as to where to draw the line.  I've heard anthropologists try to put it back there when aboriginals burned huge tracts of forest in order to create more open savannahs better suited for hunting.  But I can see the point here is that none of those earlier alterations of landscape were really global in scale.  

[joigus]

It's always going to be ambiguous. You need sedimentary deposits in order to have a clear-cut boundary that tells you when things really started to really go this or that way on a global level. You have to give geology some time.

[guidoLamoto]

Publish or perish, I guess, even if you publish things that don't need to be published or thought them out very well.

While H. sapiens and no doubt earlier H species have altered their environments to some extent, does it come anywhere near the impact that photosynthesizing bacteria had on turning Earth's reducing atmosphere into an oxidizing one, or the effect of carbon fixing diatoms have had on producing the vast limestone deposits of the American Midwest, the marble backbone of Italy or the White Cliffs of Dover?...and all the humus in the world was produced by biological activity....Beavers have had a significant and far-reaching impact on their ecosystem, and then there's coral. There would be no Florida if there hadn't been coral.

Human impacts have been and will continue to be miniscule in The Great Scheme of Things.