Geology of Crumbled Rock's Vineyards


The Crumbled Rock story began 17 million years ago when more than 500 feet of lava flows from the Columbia River Basalts covered the area now known as the Red Hills of Dundee.  The climate was sub-tropical to tropical, with high temperatures, humidity and abundant rainfall.  This hot, humid climate weathered the surface of the basalt, forming a layer of soil and weathered rock more than 80 feet thick in places.  

Tectonic forces uplifted the Coast Range and formed the Willamette Valley.  Uplifted basalt with its layer of weathered rock formed the crests of the Red Hills of Dundee, the Eola Hills and the Chehalem Mountains.  

Today, the upper portion of this weathered rock layer is Jory soil.  Below the soil is a zone of highly weathered rock.  The weathered rock in this lower layer can literally be crumbled with your hands.  

The hillside Jory soil and underlying crumbled rock make the perfect medium for growing wine grapes.  The soil retains sufficient moisture to sustain the vines throughout dry summers without the need for irrigation, yet stresses the vines to develop the distinctive Red Hills flavor. What would Oregon Pinot be without Crumbled Rock?

In the late 1800s and early 1900s, the United States Geological Survey (USGS) published geologic maps of select areas of the United States in folios.  These folios include maps of the area with topography, geology, structural cross-sections, and economic resources. Although out of print for years; they remain a valuable resource in geologic investigations.

The Crumbled Rock label pays tribute to our geologic heritage and to the contribution of soil to the terroir of the Dundee Hills.

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