ABSTRACT The geomorphology, soils, and climate of Columbia Basin vineyards are the result of a complex and dynamic geologic history that includes the Earth's youngest flood basalts, an active fold belt, and repeated cataclysmic flooding. Miocene basalt of the Columbia River Basalt Group forms the bedrock for most vineyards. The basalt has been folded by north-south compression, creating the Yakima fold belt, a series of relatively tight anticlines separated by broad synclines. Topography related to these structures has strongly influenced the boundaries of many of the Columbia Basin's American Viticultural Areas (AVAs). Water gaps in the anticlinal ridges of the Yakima fold belt restrict cold air drainage from the broad synclinal basins where many vineyards are located, enhancing the development of temperature inversions and locally increasing diurnal temperature variations. Vineyards planted on the southern limbs of Yakima fold belt anticlines benefit from enhanced solar radiation and cold air drainage. Most Columbia Basin vineyards are planted in soils formed in eolian sediment that is primarily derived from the deposits of Pleistocene glacial outburst floods. The mineralogy of the eolian sediment differs substantially from the underlying basalt. Vineyard soil chemistry is thus more complex in areas where eolian sediment is comparatively thin and basalt regolith lies within the rooting zone. The components of physical terroir that broadly characterize the Columbia Basin, such as those described above, vary substantially both between and within its AVAs. The vineyards visited on this field trip are representative of both their AVAs and the variability of terroir within the Columbia Basin.

Abstract This trip will cover the terroir (geology, climate, and other natural factors) affecting the quality of Colorado's western slope vineyards and the wines produced. On May 17 the group will make a few key geology overview stops through the Rocky Mountains en route to the wine country on the western slope near Grand Junction. On the western slope the physical factors that allow great wine grapes to be grown in Colorado will be explored and these factors will be compared to other wine viticultural areas in the world. The first day vineyards and wineries will be visited for tasting and discussion of terroir, followed by a banquet dinner and a lecture by Meinert on terroir of some of the other wine regions of the world. The group will spend the night in Grand Junction and on May 18 other wineries will be visited for tasting and terroir discussion; lunch will be at the Canyon Wind winery, with a return to Keystone (and Denver) in the late afternoon. At the end of this chapter, two geological maps (eastern half and western half) show the route of the field trip with trip stops and geological features. These maps are draped on a hillshade of a 90-meter DEM; geological data modified from Green (1992). An 11″×17″-format simplified geological map of Colorado also will be handed out as a reference for the geological transect.

Abstract This trip will cover the terroir (geology, climate, and other natural factors) affecting the quality of Colorado's western slope vineyards and the wines produced. On May 17 the group will make a few key geology overview stops through the Rocky Mountains en route to the wine country on the western slope near Grand Junction. On the western slope the physical factors that allow great wine grapes to be grown in Colorado will be explored and these factors will be compared to other wine viticultural areas in the world. The first day vineyards and wineries will be visited for tasting and discussion of terroir, followed by a banquet dinner and a lecture by Meinert on terroir of some of the other wine regions of the world. The group will spend the night in Grand Junction and on May 18 other wineries will be visited for tasting and terroir discussion; lunch will be at the Canyon Wind winery, with a return to Keystone (and Denver) in the late afternoon. At the end of this chapter, two geological maps (eastern half and western half) show the route of the field trip with trip stops and geological features. These maps are draped on a hillshade of a 90-meter DEM; geological data modified from Green (1992). An 11″×17″-format simplified geological map of Colorado also will be handed out as a reference for the geological transect. The geologic history of Colorado is long and complex. Precambrian metamorphic basement formed prior to ∼1.8 Ga and was intruded by three main Proterozoic granitic suites. The Proterozoic rocks are generally arranged in ENE-trending belts that young to the south and record a history of progressive accretion of terranes onto the Archean Wyoming craton. Following a major erosion event prior to the Late Cambrian, Colorado was a relatively stable craton in the lower to middle Paleozoic as recorded by a thin clastic and carbonate section with local disconformities. Three Phanerozoic orogenic events followed: the Pennsylvanian Ancestral Rocky Mountain (ARM) orogeny, the Late Cretaceous-Late Eocene Laramide orogeny, and the Neogene Rio Grande Rift orogeny. All three events formed generally north-trending fault block uplifts separated by sedimentary basins that cut across the earlier Proterozoic ENE trends. The ARM and Laramide uplifts record crustal shortening whereas the Rio Grande Rift records localized crustal extension. The ARM orogeny was followed by early Mesozoic terrestrial deposition and then state-wide accumulation of thick marine siliciclastic

Abstract Washington State is second only to California in terms of wine produced in the United States, and some of its vineyards and wines are among the world’s best. Most Washington vineyards are situated east of the Cascades on soils formed from Quaternary sediments that overlie Miocene basaltic rocks of the Columbia River Flood Basalt Province. Pleistocene fluvial sediments were deposited during cataclysmic glacial outburst floods that formed the spectacular Channeled Scabland. Late Pleistocene and Holocene sand sheets and loess form a variable mantle over outburst sediments. Rainfall for wine grape production ranges from ~6-18 in (150-450 mm) annually with a pronounced winter maximum and warm, dry summers. This field trip will examine the terroir of some of Washington’s best vineyards. Terroir involves the complex interplay of climate, soil, geology, and other physical factors that influence the character and quality of wine. These factors underpin the substantial contribution of good viticultural practice and expert winemaking. We will travel by bus over the Cascade Mountains to the Yakima Valley appellation to see the effects of rain shadow, bedrock variation, sediment and soil characteristics, and air drainage on vineyard siting; we will visit the Red Mountain appellation to examine sites with warm mesoclimate and soils from back-eddy glacial flood and eolian sediments; the next stop will be the Walla Walla Valley appellation with excellent exposures of glacial slackwater sediments (which underlie the best vineyards) as well as the United States’ largest wind energy facility. Finally, we will visit the very creatively sited Wallula Vineyard in the Columbia Valley appellation overlooking the Columbia River before returning to Seattle.

Abstract The ‘Massif de La Clape’ in Southern France is a calcareous hill with a semi-arid Mediterranean climate. All the agricultural lands are under vineyards managed by different châteaux. The objective of this work was to understand the soil system of Château X to solve a problem of vineyard mortality and to show how the exceptional variability of the soil conditions could be taken into account for optimal vineyard management. The soils of Château X are derived from sandstone that fills a basin of about 40 ha, surrounded by a calcareous formation. The study of the soil system showed the presence of four soil domains, two located at the top of the basin and mainly derived from eluviation, and two located at the bottom of the basin, which are mainly derived from illuviation. The domain located at the very bottom of the basin showed an accumulation of swelling clays in its Bt M horizon. The zones of highest vine mortality were located at the bottom of the basin, on the soil with the Bt M horizon. This mortality was explained by the strong discontinuity between the E and the Bt M horizons, with the accumulation of Cu at toxic concentrations as a consequence of lateral water flows. In this soil, root growth was hindered by the high bulk density of the Bt M horizon. In order to solve the problem of vine mortality and manage the vineyard according to the different soil conditions observed in the toposequence, several proposals are made.