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followed again in the next system, with “the most remarkable of record is the past. It is studied in order to interpret past events in

these zones of least life being the two that separate the Palaeozoic Earth’s history, and these interpretations require the application

from the Mesozoic and the Mesozoic from the Cenozoic.” of stratigraphic techniques, concepts, and principles. In spite of

Nowhere does Phillips (1860) mention a mass extinction as this detachment of the Anthropocene from the concept and use of

marking the beginning of the Triassic, and Phillips actually used chronostratigraphic units, the term Anthropocene may have

his compilation of fossil data to argue against the theory of utility. It is popular among a diverse scientific community, social

natural selection proposed the previous year by Charles Darwin. scientists, and the media. It does raise awareness that, as with

Yet, Waters et al. (2014b) cites Phillips (1840) to assert that anthropogenic climate change, the human impact on the Earth

human-induced changes to the stratigraphic record, although system is global, and that human impact may have initiated a
they are still yet to be recorded, are reason enough for officially cascade of events that will greatly alter Earth’s surface, oceans,

recognizing the Anthropocene as a new unit on the geologic time and atmosphere.

scale. In fact, many, if not most, of the ratified GSSPs are at strati- The term Anthropocene is of similar character to the term

graphic levels that do not represent major changes to the Earth Renaissance. Both refer to richly documented, revolutionary,

system, whether geologic or biologic. For example, the bases of the human activities that are dated in the Gregorian calendar. Both

Ordovician, Devonian, Carboniferous, and Permian systems are carry significant connotation. Although a precise date in calendar

placed at the lowest occurrences of single graptolite or conodont years is not specified for the Renaissance, the term is established

species. They were chosen at stratigraphic levels within boundary and conveys a singular meaning of the content of that period,

intervals that offered the best potential for reliable, worldwide where it began, how it evolved, and how it spread. The same

correlation. Waters et al. (2014b) also stated that units have histor- applies to Anthropocene if its concept is the human impact on

ically been defined on significant events, when in reality it is the Earth’s surface. Without doubt, scholars have argued over the
lack of definition of boundaries that has long plagued long- singular human creation, whether in literature, architecture, or

distance correlation of chronostratigraphic units. It is of concern art, that initiated the Renaissance, but there is no need to define

that the history and nature of chronostratigraphic units have not its beginning, because the dates and locations of the creations are

been fairly conveyed. well established. Furthermore, it would be contrary to current

Justification for defining the Anthropocene with a GSSA is practice to define its beginning at a single point in time because it

found in the Holocene and the Precambrian. Repeated statements is a cultural movement that is not tied to a single date. The same is

by Zalasiewicz et al. (2008, 2011, 2015) that the Holocene was true for the Anthropocene, whether it is a hydroelectric dam

defined by a GSSA are misleading. A formal definition of the constructed in the Italian Alps, a gold mine in South Africa, the

Holocene with its base (beginning) defined by a GSSA was never dramatic increase in carbon combustion during the Industrial

approved by ICS nor ratified by IUGS; a numerical age of 10,000 Revolution, the growth of a megacity, the clearing of rain forests,
14C yr B.P. was simply adopted by convention by the INQUA or the increase in CO2 in the atmosphere and the resulting
Holocene Commission, but it was then considered temporary increase in global surface temperatures. Is putting an official

(Walker et al., 2015). For the Precambrian, ICS adopted a set of beginning on the Anthropocene any more advantageous than on

numerical ages for the definition of boundaries between Archean the Renaissance? The only reason appears to be to give it credence

and Proterozoic Eons and between their constituent eras (Remane as a unit of the geologic time scale.

et al., 1996). However, during these eons and eras, voluminous The year 1945, proposed as the beginning of the Anthropocene,

stratigraphic records accumulated and extensive bodies of was selected because it marks the first atomic bomb explosion

plutonic and metamorphic rock were generated. Rock-based that initiated a period of atmospheric testing, the results of which

temporal classifications were established for each shield area long are seen in radionuclides in ice cores and lake cores. The radio­

ago, but global units defined by isotopic ages allowed for a global nuclides in cores can be taken as the stratigraphic signal that most

standard time scale. The GSSAs were set at large round numbers, closely coincides with what has been termed the great acceleration

but those exact values cannot be located precisely in stratigraphic of human impact on the Earth system (Steffen et al., 2007). That

sections. Remane et al. (1996) considered them as theoretical stratigraphic signal first becomes evident in deposits from 1952 to

postulates and pointed out their status only for boundary defini- 1960, the years of extensive atmospheric testing of nuclear bombs

tion in the Precambrian. Today, the ICS Subcommission on (Waters et al., 2015). Clearly, much of the human impact used as

Precambrian Stratigraphy is striving to replace the units defined evidence of the Anthropocene predates 1945 (e.g., Zalasiewicz et

by GSSAs with units defined by GSSPs, considering the latter to be al., 2011; Waters et al., 2014b). The same would be the case with

GSA TODAY | MARCH/APRIL 2016 more useful (Van Kranendonk et al., 2008). It is of concern that the term Renaissance, if it was arbitrarily but objectively defined

proponents of the Anthropocene do not fully explain the origin by the year 1500, when the influence of the Renaissance spread

and concept of GSSAs. from Italy to the rest of Europe. It would result in the first works

THE NATURE AND UTILITY OF THE ANTHROPOCENE of the Renaissance being relegated to the Middle Ages. In this
vein, Ruddiman et al. (2015) questioned whether or not it makes

The Anthropocene, as currently popularized, is fundamentally sense to define the start of the human-dominated time long after
different from the chronostratigraphic units that are the charge of deforestation and agriculture changed the landscape and after
the ICS. It is the present and future versus the past. Events and greenhouse gases had been rising due to agricultural and indus-
effects and impact are observed, measured, and documented by trial emissions. Proponents of the Anthropocene are thus left with
humans as they occur and are dated with the Gregorian calendar the question of whether or not a beginning of the Anthropocene
(Wolff, 2014), and geologic events are too (e.g., 1906 San Francisco should be set and, if so, when. They must also consider how this
earthquake, 1980 eruption of Mount St. Helens). The stratigraphic affects the utility of the term as used not just by stratigraphers but

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