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2012). Although some aspects of the Great Figure 2. Landsat images of Las Vegas, Nevada, USA, in 1984 (left) and 2016 (right) showing the loss
Acceleration are predicted to plateau (pop- of light-colored Quaternary wetland deposits to urban expansion. The boundaries of Tule Springs
ulation), other factors such as primary Fossil Beds National Monument (TUSK), which preserve nearly 23,000 acres of the wetland depos-
energy use (energy consumption) show no its, are shown in the righthand image. Images are courtesy of the Earth Resources Observation and
sign of slowing down. In other words, even Science (EROS) Center.
though global population is predicted to
level off perhaps around 10 billion by the valley were paved over or otherwise now. Now is also the time to focus on
end of this century, increases in the extrac- destroyed during the urban expansion (Fig. training the next generation of geologists
tion and utilization of Earth’s resources are 2). Hundreds of square kilometers of the because it can take years to hone the skills
predicted to continue (Steffen et al., 2015). deposits were wiped out in just three required to interpret and decipher these
decades. Fortunately, the last contiguous complex records.
Humans are now the dominant geomor- vestiges of the Las Vegas deposits, spanning
phic agent on Earth, transporting more nearly 23,000 acres, were protected in 2014 REFERENCES CITED
sediment with heavy equipment than the as Tule Springs Fossil Beds National
combined actions of water, wind, and ice Monument. Owing to their preservation and Hooke, R.L., 1994, On the efficacy of humans
(Hooke et al., 2012; Hooke, 1994). But it subsequent study, we now know that these as geomorphic agents: GSA Today, v. 4, no. 9,
is not just bulldozers that are affecting the deposits provide some of the most detailed p. 224–226.
surficial geologic record. Topsoil and sur- records for understanding how desert wet-
ficial sediments are being disturbed and land ecosystems responded to abrupt climate Hooke, R.L., Martin-Duque, J.F., and Pedraza, J.,
eroded at unprecedented scales by con- change during the late Quaternary (Springer 2012, Land transformation by humans: A review:
ventional agriculture, increasing rates of et al., 2015). Had the monument not been GSA Today, v. 22, no. 12, p. 4–10, doi:10.1130/
erosion by orders of magnitude over established, such studies would not have GSAT151A.1.
background levels (Montgomery, 2007). been possible.
Alteration of Earth’s surface is also Montgomery, D.R., 2007, Is agriculture eroding
occurring at a rapid pace in urban and The preservation of the Las Vegas civilization’s foundation?: GSA Today, v. 17,
suburban areas, as well as coastal regions, deposits is an exception rather than the no. 10, p. 4–9, doi:10.1130/GSAT01710A.1.
in step with increases in global popula- rule as the Great Acceleration marches on.
tion, GDP, and primary energy use, lead- Even in the most remote areas on Earth, Springer, K.B., Manker, C.R., and Pigati, J.S.,
ing to the widespread loss of the surficial from the high Arctic to the driest deserts, 2015, Dynamic response of desert wetlands to
geologic record. we are seeing massive alterations of the abrupt climate change: Proceedings of the
landscape due to the extraction of National Academy of Sciences USA, v. 112,
IDENTIFYING AND STUDYING resources to meet human demands. We no. 47, p. 14,522–14,526, doi:10.1073/
AT-RISK DEPOSITS suggest that Google’s Timelapse feature pnas.1513352112.
can be used in concert with surficial geo-
It is imperative that geoscientists iden- logic maps to identify locations where Steffen, W., Sanderson, R.A., Tyson, P.D., Jäger, J.,
tify areas containing surficial deposits that deposits are threatened, allowing scientists Matson, P.A., Moore, B., III, Oldfield, F.,
are most at risk. A new tool, the Timelapse to study them before it is too late. Richardson, K., Schellnhuber, H.-J., Turner,
feature in Google Earth Engine1, vividly B.L., and Wasson, R.J., 2004, Global Change
shows the remarkable impact that humans A key concern and question is “How and the Earth System: A Planet under Pressure:
are having on the landscape. Combining much time do we have?” The answer The IGBP Book Series: Berlin, Heidelberg, New
multiple sources of satellite imagery, depends upon the prioritization of research York, Springer-Verlag, 336 p.
Timelapse allows users to track changes, questions, the availability of funding and
determine or follow trends, and quantify resources, and the measures taken to pre- Steffen, W., Broadgate, W., Deutsch, L., Gaffney,
differences in land use that have occurred serve the deposits in select cases. Clearly, O., and Ludwig, C., 2015, The trajectory of the
during a 32-year period (1984–2016). It is for those interested in studying the surfi- Anthropocene: The Great Acceleration: The
an especially timely and effective tool for cial geologic record, the time to do so is Anthropocene Review, v. 2, no. 1, p. 81–98,
geologists that are interested in studying doi:10.1177/2053019614564785.
surficial deposits.
Zalasiewicz, J., Crutzen, P., and Steffen, W., 2012,
A particularly striking example of the The Anthropocene, in Gradstein, F.M., Ogg,
visual power of this new tool is the Las J.G., Schmitz, M., et al., eds., A Geological Time
Vegas Valley of southern Nevada. Since Scale 2012: Amsterdam, Elsevier, p. 1033–1040.
1980, Clark County (Las Vegas metropoli-
tan area) has experienced a nearly fivefold Manuscript received 31 March 2017
increase in population to over two million Revised manuscript received 15 July 2017
people. As the cities of Las Vegas, North Manuscript accepted 24 July 2017
Las Vegas, and Henderson burgeoned, fos-
sil-rich deposits associated with springs and
wetlands that once covered most of the

1 The Timelapse feature can be accessed online at https://earthengine.google.com/timelapse/. (Note that any use of trade, firm, or product names is for descriptive
purposes only and does not imply endorsement by the U.S. government.)

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