The idea that we’re in a human-influenced geological epoch is gaining traction, but how will future geologists measure it? Rachel Brazil finds out The idea for the Anthropocene came from a chemist – the Nobel prize-winning atmospheric chemist Paul Crutzen, who sadly died on 28 January this year. In 2000 he suggested that we are now in a new geological epoch, marked by the activities of humans. The idea caught the attention of the media and wider academic community because it so well encapsulated the changes that have led to our current climate crisis. But Crutzen’s statement also chimed with some geologists, who started to consider whether there really was a case for formally defining a new unit within the geological time scale. Since 2009 they have been searching for the chemical signals that would mark this new epoch.