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Following the recent rejection of a formal Anthropocene series/epoch by the Subcommission on Quaternary Stratigraphy (SQS) of the International Commission on Stratigraphy (ICS), and its subsequent confirmation by the International Union of Geological Sciences (IUGS), the opportunity arises to reset the definition of the Anthropocene. The case for informally recognizing the Anthropocene to be a major planetary event of Earth system transformation offers a promising way forward, but this has been criticized by proponents of an Anthropocene series/epoch. In order to move on from the assumption that it must be a time interval, and to foster a more transdisciplinary and inclusive approach, the main points of the critique must be directly addressed. Plain Language Summary: The Anthropocene is best understood as an unfolding and intensifying event of human‐influenced Earth system change. Here we respond to criticisms of the case for the Anthropocene Event and explain why attention should be shifted away from the narrow question of date of start which has dominated debate up to now. The Anthropocene, we argue, is more than just a time interval. It is first and foremost a material happening or physical transformation which unfolds through time. Interdisciplinary research on the Anthropocene is more important than ever and must continue apace. Key Points: The Anthropocene is best studied as an ongoing event of human‐influenced planetary transformation rather than a time intervalThe Great Acceleration is an intensification of a larger unfolding Anthropocene Event that is spatially and temporally heterogeneousInterdisciplinary research on the Anthropocene is now more important than ever [ABSTRACT FROM AUTHOR]

Current debate on the status and character of the Anthropocene is focussed on whether this interval of geological time should be designated as a formal unit of epoch/series rank in the International Chronostratigraphic Chart/Geological Time Scale, or whether it is more appropriate for it to be considered as an informal 'event' comparable in significance with other major transformative events in deeper geological time. The case for formalizing the Anthropocene as a chronostratigraphical unit with a base at approximately 1950 CE is being developed by the Anthropocene Working Group of the Subcommission on Quaternary Stratigraphy. Here we outline the alternative position and explain why the time‐transgressive nature of human impact on global environmental systems that is reflected in the recent stratigraphical record means that the Anthropocene is better seen not as a series/epoch with a fixed lower boundary, but rather as an unfolding, transforming and intensifying geological event. The case for formalising the Anthropocene as a chronostratigraphic unit with a base at approximately 1950 CE is being developed by the Anthropocene Working Group of the Subcommission on Quaternary Stratigraphy. Here we outline the alternative position and explain why the time‐transgressive nature of human impact on global environmental systems is more accurately reflected by defining the Anthropocene as a continuing event, with no fixed basal boundary. [ABSTRACT FROM AUTHOR]

Integrated sequence stratigraphic, biostratigraphic, and chemostratigraphic analyses of three stratigraphic sections in central Nevada indicate that Late Ordovician glaciation-induced sea-level fall produced diachronous, stepwise faunal turnover in graptolites, conodonts, chitinozoans, and radiolarians, and also triggered a strong, but transient, positive [[Delta].sup.13]C excursion. This pattern is very different from that described for most mass extinction events.

Graptolite-rich shale in the Valley and Ridge province of Alabama, Georgia, Tennessee, and Virginia records subsidence and migration of the Sevier foreland basin, which formed in response to arc-continent collision during the Middle Ordovician Blountian phase of the Taconic orogeny. Rapid, tectonically induced subsidence of what had been a shallow carbonate platform led to pelagic deposition of graptolite shale in a deep basinal setting. The contact of the shale with the underlying carbonate rocks is a distinct record of initiation of subsidence. Graptolites were collected extensively and systematically from the shale at 50 localities in the southern Appalachians. Correlation with zonal biostratigraphy demonstrated that the shale sequence is diachronous. In localities to the southeast, in Alabama and Georgia, it correlates with the Didymograptus murchisoni Zone. To the northwest, across strike in Alabama, Tennessee, and Virginia, the shale becomes progressively younger and correlates sequentially with the Glyptograptus teretiusculus, Nemagraptus gracilis, and Climacograptus bicornis Zones. This diachronism records the northwestward, cratonward migration of the foreland basin, which was driven by postcollisional plate convergence. Biostratigraphic data from 22 localities were amenable to analysis by graphic correlation. At these localities, graptolites were collected from measured sections, and ranges of all species in the 22 sections were compiled into a CSRS (composite standard reference section) that correlates with the biostratigraphic interval from the G. teretiusculus Zone to the C. bicornis Zone. On the basis of the most reliable radiometric ages correlated into the graptolite zonation, the duration of the composite standard reference section is estimated to be 5 m.y. It is divisible into 89 CSUs (composite standard units), each with an approximate duration of 56 000 yr. Recorrelation of each of the 22 measured sections with the composite standard reference section allowed the stratigraphic base of the shale in each section to be expressed in terms of composite standard units, and such correlations permitted the diachronism of the basal shale contact to be measured with much greater precision than with zonal biostratigraphy. In addition, age differences of the basal shale contact between sections can be expressed in terms of time. With the temporal information provided by the composite standard reference section and original distances between sections determined from a palinspastic reconstruction, the rate of migration of the foreland basin as recorded in the diachronous basal shale contact was determined. Between sections in northeastern Tennessee and adjacent Virginia, calculated rates averaged 13 mm/yr and decreased northwestward from 40 to 9 mm/yr. This cratonward decrease in rate may represent deceleration as foreland basin migration, and the arc-continent collision that drove it, slowed to a halt. The rate of 40 mm/yr may be considered as the maximum rate of plate convergence following arc-continent collision. Precollisional plate convergence rates may have been significantly greater. The rate of 40 mm/yr is, however, well within the range of modern rates of plate convergence. In addition, the deceleration recorded in the Sevier foreland basin is similar to the deceleration of post-collisional plate convergence at the Timor Trough.

Given the long established, rigorous stratigraphic basis on which chronostratigraphic units and their boundaries are established, the call by Chvostek ([1]) to invite the Human(ities) to the Anthropocene Series/Epoch must be rejected. Keywords: Anthropocene; epoch; event; series; stratigraphy EN Anthropocene epoch event series stratigraphy 461 462 2 05/09/23 20230501 NES 230501 The endeavour over the last 15 years to formalize an Anthropocene Series/Epoch has generated great publicity ranging from scientific articles by members of the Anthropocene Working Group (AWG) and a range of other earth and social scientists (Head et al. [8]; Waters and Turner, [11]) to articles for the public in newspapers and magazines worldwide. [Extracted from the article]