Every era in the history of the Earth has left a distinct legacy that makes it unique from other periods. Now, experts think time has come to establish a new geological epoch that marks human activity on Earth - the Anthropocene.
A group of international geoscientists from the Anthropocene Working Group think the evidences have become quite overwhelming that it calls for a formalization.
Unlike the Holocene, which gave rise to land domestication, urban settlements and effective resource development, the Anthropocene epoch centralizes more on how human activity instigated environmental changes. Such modifications are said to be a result of human population boom and the rise in resource usage during the Great Acceleration era of the mid-20th century.
The environmental changes that the scientists pertain to include the widespread presence of plastics, fly ash, pesticides, metals, reactive nitrogen and other products as a result of increased greenhouse gas emissions.
"All of these show that there is an underlying reality to the Anthropocene concept," says co-author and working Chair Jan Zalasiewicz from the University of Leicester.
Indicators Of A New Geologic Epoch
In recent investigations, experts found anthropogenic deposits of new minerals and rocks, signifying the swift spread of new materials all over the world. Such novel objects include concrete, elemental aluminum and so-called "technofossils," which rapidly and abundantly evolve from plastics.
Experts also consider the increase of fossil fuel combustion, which dispersed inorganic ash spheres and black carbon all over the planet.
More and more anthropogenic sediments including enhanced erosion due to road constructions and deforestation continue to spread.
"Widespread sediment retention behind dams has amplified delta subsidence," the authors write.
Experts also see a rise in radionuclides formed from nuclear weapon testings in the atmosphere. During the early parts of the 1950s and 1960, hydrogen bomb tests generated radioactive fallout, which future scientists may use as a geological time indicator millions of years from now.
Defining The New Epoch
Establishing a new epoch means identifying particular details that comprise it. Experts need to specify when the geological period officially started, its unique characterizations and how different it is from the previous era.
This year, the authors will continue their work and gather more evidences about the proposed epoch. Their work may help formulate recommendations on whether this new period should be formalized or not.
The study was published in the journal Science on Friday, Jan. 8.