MISINFORMATION IN THE ANTHROPOCENE

Paul Crutzen and colleagues argued that the Earth system is in a new geologic age, the Anthropocene Epoch, based on the rate and extent of human impacts on the Earth system. Subsequently, the Subcommission on Quaternary Stratigraphy of the International Commission on Stratigraphy (ICS) established the Anthropocene Working Group (AWG) to consider whether the stratigraphic record justified the establishment of a new chronostratigraphic unit that would serve as the material basis for a new geochronologic unit. The concept followed by the leaders of the AWG was that these units are associated with major changes in the fossil contents of rocks below and above a particular horizon and that to warrant epoch status the scale of changes in key stratigraphic criteria need to be of comparable magnitude to those used as evidence for earlier epoch boundaries. However, it is evident that Crutzen and colleagues gave no consideration to the nature of the units of the geologic time scale as defined by ICS and that the AWG has promulgated a false concept - that the scale of changes at the boundary of a unit is the basis on which to define a unit and its rank. Unfortunately, that false concept is now the basis for almost all discussions on an Anthropocene Epoch. The essential criteria for defining the lower boundary of a chronostratigrarphic unit is that it is placed in a stratotype section at a level that coincides with a stratigraphic signal that offers the potential for reliable correlation as widely as possible. Most units of the ICS International Chronostratigraphic Chart have boundaries placed at the lowest stratigraphic occurrence of a single species or subspecies, preferably within an evolutionary lineage. The lower boundaries of some stages – the lowest global chronostratigraphic rank – occur at major changes (e.g., the Late Ordovician mass extinction), while those of much higher rank, such as the base of the Devonian System, are defined on very minor changes. And the Cretaceous System has never had a lower boundary defined even though it was established more than 200 years ago. It is apparent that many authors who publish articles on the Anthropocene are ignorant on the history and nature of the units defined by the International Commission on Stratigraphy. The boundaries of the units of the geologic time scale as defined by ICS are not based on the magnitude of changes at those boundaries.