OMSI Science Pub: Terroir in Oregon

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



Tuesday, May 6