SOUTHERN OREGON GEOLOGY & SOILS
UPDATED 4.1.17
This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
OPEN A BOTTLE OF OREGON WINE AND TASTE A 200- MILLION-YEAR-OLD STORY.
Quite a feat for humble grapes that fought for existence in infertile soils. But in Oregon, we’ve always thought that struggle builds character, and our wines have that in spades. Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
SETTING THE SCENE
Oregon resides in the “Ring of Fire,” an area in the basin of the Pacific Ocean that is home to 75% of the world's volcanoes and 90% of the world's earthquakes.
50° N
30° N
0° EQUATOR
30° S ACTIVE VOLCANOES
RING OF FIRE
50° S Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
DRAMATIC EVENTS FORM SPECTACULAR LAND
Oregon’s position in the "Ring of Fire" has made for a magnificent, violent geological history that has carved dramatic landscapes and yielded some of the most diverse growing regions in the world. Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
CRATER LAKE NATIONAL PARK Image: Travel Oregon Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
SMITH ROCK STATE PARK Image: Christian Heeb Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
COLUMBIA RIVER GORGE Image: Satoshi Eto Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
PAINTED HILLS, JOHN DAY FOSSIL BEDS NATIONAL MONUMENT Image: Christian Heeb Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
Southern Oregon's predominant grapegrowing soils are the result of millions of years of geological history.
Marine Volcanic Stream
Sedimentary • Cascade Mountain Sediments Sediments Bedrock • Silezia Terrane
Images: Oregon Wine Press Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
200 MILLION YEARS AGO
PACIFIC OCEAN COAST REACHES IDAHO
SUBDUCTION ZONE • The Juan de Fuca tectonic
PACIFIC OCEAN NORTH AMERICAN plate begins to gradually PLATE subduct under the North JUAN DE FUCA PLATE American tectonic plate Columbia River • Ocean islands and pieces BLUE MOUNTAINS of the ocean bottom are "stuck" onto the West Coast as accreted terrane, creating Oregon's oldest mountains and gradually adding land PACIFIC mass to what is now Oregon OCEAN
KLAMATH
MOUNTAINS
MARINE SEDIMENTARY BEDROCK FORMS 75 M 25 M 50 M 175 M 125 M 150 M 100 M 200 M TODAY Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
MARINE SEDIMENTARY BEDROCK
Produced from ocean islands and pieces of ocean "stuck" onto West Coast as tectonic plates subducted
Higher clay content than marine sedimentary soil, resulting in a deeper red hue
Clay composition requires vines to struggle and grow very deep to reach the water table
Image: Oregon Wine Press PACIFIC OCEANOregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
50-10 MILLION YEARS AGO
VOLCANIC ERUPTIONS IN THE CASCADE MOUNTAINS
• Volcanoes in the Cascade Mountain Range erupt
• Lava covers the mountains and weathers into rich
COAST RANGE volcanic soil in what is now the northern Rogue Valley
RANGE
CASCADE
MARINE SEDIMENTARY CASCADE VOLCANIC BEDROCK FORMS SOILS FORM 75 M 25 M 50 M 175 M 125 M 150 M 100 M 200 M TODAY Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
VOLCANIC SOIL: CASCADE MOUNTAIN SEDIMENTS
Produced from the weathering of volcanic soil from the eruption of the Cascade Mountains
Soil is less red than other volcanic soil in Southern Oregon
Very clay-rich and retains a lot of water
Image: Oregon Wine Press Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
45-35 MILLION YEARS AGO PACIFIC VOLCANIC SOIL UPLIFTS OCEAN IN THE UMPQUA VALLEY
OCEAN • Volcanic sediment from an NORTH AMERICAN underwater eruption uplifts PLATE over time due to plate JUAN DE FUCA PLATE subduction
• Creates a pocket of volcanic soil called Silezia Terrane, defining what is now the
RED HILL Red Hill Douglas County DOUGLAS COUNTY AVA
UMPQUA VALLEY
MARINE SEDIMENTARY CASCADE VOLCANIC SILEZIA VOLCANIC BEDROCK FORMS SOILS FORM SOILS FORM 75 M 25 M 50 M 175 M 125 M 150 M 100 M 200 M TODAY Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
VOLCANIC SOIL: SILEZIA TERRANE
Produced in Southern Oregon from ancient underwater volcanic basalt being uplifted due to plate subduction
High in clay content and iron, resulting in a very distinguishable red hue
Offers fewer nutrients than marine sedimentary soil
Image: Oregon Wine Press Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
16-10 MILLION YEARS AGO
TECTONIC PLATES SHIFT
PACIFIC • The Juan de Fuca tectonic OCEAN plate continues to subduct under the North American plate, uplifting coastal sediments to form the Coast lumbia Riv Co er Range above water
r e v i R CASCADE • Cascade Mountain Range e RANGE t COAST t RANGE e SUBDUCTION forms inland above water
m ZONE
a l from the accumulation of l i PACIFIC OCEAN W NORTH AMERICAN volcanic rock PLATE
COAST RANGE
JUAN DE FUCA PLATE • Oregon accumulates enough landmass due to accreted
CASCADE RANGE terrane to be completely above water
KLAMATH
MOUNTAINS
MARINE SEDIMENTARY CASCADE VOLCANIC SILEZIA VOLCANIC BEDROCK FORMS SOILS FORM SOILS FORM 75 M 25 M 50 M 175 M 125 M 150 M 100 M 200 M TODAY W il la R m i v e e t r t e
Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
2 MILLION YEARS AGO
STREAM TERRACES AND ALLUVIAL FANS BEGIN TO FORM STREAM Ump qua R TERRACES & FANS iver • Ancient rivers shift and alter their paths often, leaving ALLUVAL FAN flat, weathered surfaces TERRACE behind called stream terraces
KLAMATH RIVER • Alluvial fans begin forming
MOUNTAINS BEDROCK around major rivers as sediments from former hillside streams move down the hillside and deposit on river terraces
Rogue River
RANGE
CASCADE
MARINE SEDIMENTARY CASCADE VOLCANIC SILEZIA VOLCANIC STREAM SEDIMENT BEDROCK FORMS SOILS FORM SOILS FORM SOILS FORM 75 M 25 M 50 M 175 M 125 M 150 M 100 M 200 M TODAY Oregon Wine Board GEOLOGY & SOILS: SOUTHERN OREGON
STREAM SEDIMENTS
Composed of silt, sand and gravel
Sediments are sorted by the velocity of the former stream; faster-moving water leaves behind larger sediments such as gravel
Soil drains very well
Image: Oregon Wine Press