Arizona, Arizona geology, Arizona Terroir, AZwine, Chino Valley, Chino Valley Wineries, Del Rio Springs Vinyeard, geology, geology and wine, Granite Mountain Vineyard, introduction, Javelina Leap, Other Arizona Wine Regions, Pinot Noir, Prescott, Prescott Region, Skull valley, terroir, Yavapai County
Chino Valley is both the second oldest and also the youngest wine growing region in Arizona, and the region which holds the most promise for cooler weather varietals, and Burgundian grapes like Chardonnay and Pinot Noir. Why is it the second oldest? Granite Creek Vineyards has been growing grapes and making wines since the 1980’s, at least as long as Sonoita.
Why is it the youngest? The potential of this region has only recently been realized with the smashing success of the new Del Rio Springs vineyards and its fantastic Pinot Noir and Carmenere. That success was so great that I am aware of at least five different people planting next spring alone. Vines are also being grown and planted now in Skull Valley as well; on the west side of Prescott.
With this boom, Chino Valley has the potential to be the next big scene for Arizona wine. But how does the geological history of the region play a role in the production of wines in this location? It’s been a long story, and many parts of the rock record are missing, but enough remains for us to be clear on certain parts of that story.
The oldest rocks in the area are the remains of yet another island arc, very simular to the one which created Jerome. These granitic rocks form most of the mountains in the Prescott area. Along with the granitic rocks are some volcanic deposits, and even some sedimentary rocks, dating all from the time of this island arc. The erosion of these granitic mountains are also the basis for much of the alluvial deposits in the area which date from the Cenozoic, but we’ll get there.
The next oldest rocks are oceanic in origin. Like so many other wine regions in Arizona, the ancient oceans which once lapped our sun-dappled tropical shores during the Paleozoic era are exposed here; these are the same seas we met in passing during our exploration of terroir in the Verde Valley which left the Tapeats Sandstone, and the Martin and Redwall limestones, during the Devonian, Mississippian, and Pennsylvanian periods, dating from about 540-310 million years ago. Fossils of trilobites and horn corals can be found in some of the rocks in this area. These rocks, overlain in some places by later volcanic rocks dating from the Oligocene, Miocene, and Pliocene form the Burgundy-like landscape of Northern Chino Valley.
It is here that Del Rio Springs vineyard is growing, which explains this vineyard’s dramatic success with Pinot Noir. (That vineyard is also growing Grüner Veltliner, Carménère, Vignoles, and will be planting Chardonnay next year; as mentioned, five other vineyards will be planted shortly in that part of the valley.) In a few places, the later Kaibab formation from the later Permian is exposed, dating from about 270 million years ago.
The next oldest rocks form some of the higher peaks near Prescott; these are granite monoliths which once formed magma chambers for the volcanoes of the Mogollon highlands during the Cretaceous period. The erosion of these mountains, and the collaspe of their cousins in the south set the stage for the next rocks in the region; volcanic rocks and alluvial deposits from the Cenezoic era from the Miocene and Pliocene.
Deposition of alluvial deposits in the wine growing regions of Skull Valley and near Granite Creek Winery continued until 2 million years ago. (In some places in valley, deposition continued into the Quaternary.) These rocks and soils are composed mostly from erosional remnants of the granitic rocks that once formed the magma chambers of the volcanoes of the Mogollon highlands, and tend to be clay-rich. I am told that the soils nearest Chino valley are similar to Rioja, but I cannot corraberate this.
That being said, this are is still quite new, and I have not drank enough here to comment as to what effect the local terroir has on wines grown in these areas, and I think we can only safely comment on that fact until after more wines, and more vineyards begin growing and production in what I feel will become one of Arizona’s most facinating wine regions; a place where one could potentially grow Pinot Noir and Tempranillo within 15 miles of each other!
Not only that, I was just informed that there’s a few secret vineyards controlled by Javelina Leap in this area that provide Cabernet Sauvignon, Sangiovese, Barbera, Tempranillo, and Cabernet Franc. I barrel tasted the Cab from this “Secret Vineyard,” and while young, it was delightfully smoky and complex. There’s a lot of untapped potential in this region, and I’d like to see it take off!