The Mystery of Terroir in Oregon: The Relationship of Geology, Soils, and Climate to Wine
with Scott Burns, professor Emeritus of geology at Portland State University
Wines differ from each other based on seven different factors: the
type of grape; the bedrock geology and resulting soils; the climate;
the soil hydrology; the physiography of the site; the winemaker; and
the vineyard management techniques. The first five of these factors
make up what the French call terroir, “the taste of the place”.
Bedrocks weather into soils which then liberate chemical nutrients to
the grape vines. Twelve of the sixteen essential elements for wine
grapes come from the soil. All around the world the geology and soils
make up an important component of the terroir of the wine. Using
examples from the Willamette Valley of Oregon, terroir of the region
will be discussed because it is strongly influenced by the bedrock
geology and soils. The three dominant groups are the volcanic soils
(the Jory Series), which developed on the Columbia River Basalts; the
windblown silt soils (Laurelwood Series) and the Willakenzie Series of
soils, developed on uplifted marine sedimentary rocks in the foothills
of the Oregon Coast Range. The wines made from the grapes of these two
soils are very different.
Scott Burns, PhD, is a professor Emeritus of geology and past chair of
the Department of Geology at Portland State University where he has
taught for over 20 years. He has a B.S. degree in chemistry and a M.S.
degree in physical sciences from Stanford University and a PhD in
geology from the University of Colorado, Boulder. Dr. Burns
specializes in environmental and engineering geology, geomorphology,
soils, and quaternary geology. In Oregon, his projects involve
landslides and land use, environmental cleanup of service stations,
slope stability, earthquake hazard mapping, the Missoula Floods,
paleosols, loess soil stratigraphy, radon generation from soils, and
the distribution of heavy metals and trace elements in Oregon soils
and alpine soil development. He has won many awards for outstanding
teaching and his work in geology, including the Distinguished Faculty
Award from the Portland State Alumni Association in 2001, the Richard
Jahns Award for engineering geology from GSA and AEG in 2011, and the
Outstanding Scientist for Oregon for 2014 from the Oregon Academy of
Sciences. He has authored more than 100 publications and received more
than 25 research grants. Dr. Burns actively helps local TV and radio
stations and newspapers bring important geological news to the public
and, for the past 43 years, has been studying wine and terroir—the
relationship between wine, soils, geology, and climate.
SCIENCE PUB PORTLAND – Hollywood Theatre
is a monthly event open to anyone aged 21+ (or minor with adult). No RSVP or scientific background required. Just bring your curiosity, sense of humor, and appetite for food, drinks, and knowledge! Questions? E-mail sciencepub@omsi.edu.