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The “Anthropocene” epoch: Scientific decision or
political statement?
GSA TODAY | MARCH/APRIL 2016 Stanley C. Finney*, Dept. of Geological Sciences, California
State University at Long Beach, Long Beach, California 90277,
USA; and Lucy E. Edwards**, U.S. Geological Survey, Reston,
Virginia 20192, USA
ABSTRACT
The proposal for the “Anthropocene” epoch as a formal unit of
the geologic time scale has received extensive attention in scien-
tific and public media. However, most articles on the
Anthropocene misrepresent the nature of the units of the
International Chronostratigraphic Chart, which is produced by
the International Commission on Stratigraphy (ICS) and serves as
the basis for the geologic time scale. The stratigraphic record of
the Anthropocene is minimal, especially with its recently
proposed beginning in 1945; it is that of a human lifespan, and
that definition relegates considerable anthropogenic change to a
“pre-Anthropocene.” The utility of the Anthropocene requires
careful consideration by its various potential users. Its concept is
fundamentally different from the chronostratigraphic units that
are established by ICS in that the documentation and study of the
human impact on the Earth system are based more on direct
human observation than on a stratigraphic record. The drive to
officially recognize the Anthropocene may, in fact, be political
rather than scientific.
INTRODUCTION
Since the publication in GSA Today of the article titled, “Are we
now living in the Anthropocene?” (Zalasiewicz et al., 2008), the
proposal that a new epoch in the geologic time scale called the
“Anthropocene” be established has received greatly increasing
attention in both scientific and public media (e.g., Nature,
Scientific American, Science, Geoscientist, The New York Times,
Los Angeles Times, The Economist, National Geographic, Der Spiegel
online, to name a few). This attention arises from the desire by
some for official recognition of the impact of humans on the
Earth system, specifically its surface environments. A 2011 edito-
rial in Nature asked, “Geologists are used to dealing with heavy
subjects, so who better to decide on one of the more profound
debates of the time: does human impact on the planet deserve to
be officially recognized? Are we living in a new geological
epoch—the Anthropocene?” The editorial answered the ques-
tions as follows:
GSA Today, v. 26, no. 3–4, doi: 10.1130/GSATG270A.1.
*Chair, International Commission on Stratigraphy
**Commissioner, North American Commission on Stratigraphic Nomenclature
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Official recognition of the concept would invite
cross-disciplinary science. And it would encourage a mindset
that will be important not only to fully understand the
transformation now occurring but to take action to control it. …
Humans may yet ensure that these early years of the
Anthropocene are a geological glitch and not just a prelude
to a far more severe disruption. But the first step is to recognize,
as the term Anthropocene invites us to do, that we are
in the driver’s seat. (Nature, 2011, p. 254)
That editorial, as with most articles on the Anthropocene, did
not consider the mission of the International Commission on
Stratigraphy (ICS), nor did it present an understanding of the
nature of the units of the International Chronostratigraphic Chart
on which the units of the geologic time scale are based. We take
this opportunity to provide the greater geoscience community
with an understanding of the charge of the ICS and an apprecia-
tion of the history and nature of the units of the International
Chronostratigraphic Chart. We compare the concept of
Anthropocene to that of the systems, series, and stages of the
International Chronostratigraphic Chart. We examine its useful-
ness as a unit defined by the criteria in the International
Stratigraphic Guide (http://www.stratigraphy.org/index.php/
ics-stratigraphicguide). We address the question of whether or not
the International Commission on Stratigraphy is being asked to
make what is in effect a political statement.
THE ICS AND THE INTERNATIONAL
CHRONOSTRATIGRAPHIC CHART
The ICS, the largest constituent scientific body in the
International Union of Geological Sciences (IUGS), is composed
of a three-person executive board and 16 subcommissions, each
with ~20 voting members, who together represent more than
50 countries. Its charge is to define a single hierarchal set of global
chronostratigraphic units with precisely defined boundaries that
can be correlated as widely as possible. Boundaries are selected at
levels that best set limits to the chronostratigraphic unit that they
delimit, and boundary definition employs the concept of Global
Standard Stratotype Section and Point (GSSP) as set out in the
International Stratigraphic Guide (Salvador, 1994) and in revised
ICS guidelines (Remane et al., 1996). The web-based archive of
the chronostratigraphic units and GSSPs approved by ICS and