Origin: A Genetic History of the Americas

to confirm that the stratigraphic layers containing the bison and stone tools
were probably from the late Pleistocene (6).
GEOARCHAEOLOGY
Geoarchaeology is the application of geologic principles and
methods to the solution of archaeological questions.
Early geoarchaeologists in the Americas during the late 19th
and early 20th centuries did much of the work to establish
chronologies for archaeological sites before the advent of
radiocarbon dating by correlating stratigraphic layers with
climatic events.
Contemporary geoarchaeologists use sophisticated
approaches to address complex questions in the research of a
particular site. First, they aim to understand the nature of the
landscape and environment during a site’s use. This
environmental backdrop can tell us a lot about the ancient
peoples’ priorities and choices. For example, geoarchaeologists
ask why people might have chosen to live in a specific place.
Was it close to water? Did it offer access to (or control of)
certain plants, tool stone, or animal resources? Were there
geological features that gave protection from the weather (or
rival groups of people)?
Another goal of geoarchaeology is to reconstruct how a site
was formed. To understand site formation processes,
geoarchaeologists “read” the profiles of sedimentary deposits
and soils—which together make up the site’s stratigraphic
sequence. They place this stratigraphic sequence in the context
of surrounding regions and other sites. This context provides
information for essential understanding of who was using the
site, when they were using it, and their activities. For example,
by reconstructing the formation processes at a particular site,
geoarchaeologists could tell us not only that it was abandoned
300 years after it was formed, they could potentially tell us why
it was abandoned. They might be able to correlate the