There is a saying among winemakers that "great wine begins with dirt." Beginning from this intriguing premise, The Winemaker's Dance embarks on an eye-opening exploration of "terroir" in one of the greatest places on earth to grow wine―California's Napa Valley. Jonathan Swinchatt and David G. Howell weave a tale that begins millions of years ago with the clash of continental plates that created the Napa Valley and go on to show how this small region, with its myriad microclimates, complex geologic history, and dedicated winemakers, came to produce world-class wines. A fascinating look at the art and science of winemaking and the only comprehensive book that covers Napa's geology, history, and environment, The Winemaker's Dance will help wine enthusiasts better understand wine talk and wine writing and, most importantly, wine itself.
The Winemaker's Dance is animated by the voices of Napa's winemakers talking about their craft. The book also contains two driving tours through the valley that highlight the landscapes and wineries discussed. An array of unique illustrations―including shaded relief maps overlaid with color aerial photographs―provide a new and illuminating look at the its bedrock, sediments, soils, sun, wind, and rain. The expansive narrative considers how these elements influence wines from particular vineyards and how specific winemaking practices can bring out or mask aspects of terroir. It concludes with a discussion of the state of the winemaking industry today.
Unraveling the complex relationship between the people, the earth, and the vines of Napa Valley, The Winemaker's Dance brings the elusive concept of terroir to a broad audience, adding a vibrant dimension to the experience of the valley's wines. It also provides insights that enhance our understanding of wines and winegrowing regions the world over.
I read this book because I wanted to learn more about the geology of Napa (the first half of the book). The second half of the book was about winemaking, which wasn't as interesting to me.
But the authors were clearly passionate about geology. The geology part of the book is beautifully illustrated, and since it focuses on a very small region (the Napa valley), it goes into great depth about things that other Californian geology books I've read skimmed over or didn't cover.
First of all, the book discusses the origins of the Napa Valley. I felt like the book did a great job of explaining and illustrating this, much better than the many other books (at this point) that I've read about the geology of California. Unfortunately, this book was written in 2002 so I'm not sure if its explanation of things is outdated, but I still found it very interesting. I understood that the Central Valley was formed when the thrust fault (subduction zone) between the Farallon Plate and the North American plate leapt something like 80 miles from where the Sierra Nevadas currently are to where the San Andreas fault is today. The oceanic crust of that section of the Farallon Plate forms the basement of what is known today as the "Great Valley Sequence" that underlies the Central Valley. The book explained that at this time, the coast ranges did not exist, so there was basically a long slope from the ancestral Sierra Nevadas to the Pacific Ocean. The Sierra Nevadas were so heavy that they caused the crust beneath them to since. This also pushed down much of the Great Valley Sequence, but it caused the far away edge of the Great Valley Sequence to bulge up in response. The dip between the far edge of the Great Valley Sequence and the Sierra Nevadas would, over millions of years, fill up with 50,000 ft (!!!) of sediment. Meanwhile, the islands and gunk of the Farallon Plate, which was subducting beneath the bulged up edge of the Great Valley Sequence, scraped against it, forming what is now known as "Franciscan melange". The Farallon, Pacific, and North American plates touched at a "triple junction" that has been acting as a zipper, where basically the Pacific and North American plates are zipping together and annihilating the Farallon Plate. This is still occurring to this day (the remnant of the Farallon plate is called the Juan de Fuca plate and the triple junction is off the coast of Mendocino). When this triple junction passed near what is now Napa, the Coastal Ranges did not yet exist; the coast was relatively flat. The triple junction caused significant volcanic activity that covered the entire area in various types of lava. As the Farallon plate disappeared under the North American plate and the Pacific and North American plates touched to form the San Andreas fault, although the San Andreas fault is a transform fault that moves sideways, it also has some lateral movement. This lateral movement sometimes stretched and sometimes squished the crust. Recently, the lateral movement has been squishing the crust, causing the uplift of the Coast Ranges including the Mayacamas and Vaca mountain range that define the west and east edges of Napa.
Second of all, the book discusses how the end of the last Ice Age affected the Napa valley. During the last Ice Age, sea levels were over 300 feet lower, so the San Fransisco Bay did not exist. It was a valley with rivers running through it and out of what is now the Golden Gate bridge into the Pacific Ocean. Therefore the Napa River was far from its "base level" when it ran through the Napa valley, meaning its course was steeper back then, resulting in it flushing out most sediments from the valley. However, when sea level rose and "base level" became the nearby San Pablo Bay, the Napa River slowed down and entered base level at almost the mouth of the valley. This resulted in significant amounts of sediment being deposited along the length of the valley. Therefore, most of the sediments on the valley floor date from since the last Ice Age.
Third, the book discussed the origin of the many little hills that are scattered across the Napa valley floor. I thought that those hills were volcanic in origin, but the authors claim that most of the hills are actually the "toes" of massive landslides. The Mayacamas (west side of Napa) and Vaca (east side of Napa) mountain ranges arose as the San Andreas fault squished into the North American plate (it mostly moves north but sometimes has a small eastward vector as well). The rapid uplift of the Vaca mountains in particular apparently created instability that resulted in large portions of the Vaca mountains caving down. As the mountainsides collapsed, the base of the collapse pushed up into a "toe", result in the ridges and bumps within the Napa valley. These ridges and bumps were probably a lot more pronounced during the last Ice Age, but they have since been partly buried by sediment.
Lastly, the book talked about the many "alluvial fans" that have been deposited by rivers from the Mayacamas and Vaca mountains entering the Napa valley. The area of the Napa river flood plain itself is composed of "fluvial" sediments, mostly finer silts deposited by the river during floods. But along the edges of the valley, tributary streams coursing quickly down the mountains lower gradient of the valley floor and dump their coarse sediment load. The book explains how this results in the formation of alluvial fans - over a long period of time, the river will build up its course with deposited sediments, depositing levees and raising its bed. Eventually during a flood, the river will overflow its levees and find a new course. Over thousands of years, the accumulation of all of these raised beds will form a fan shape. I thought that was interesting. The fan shape doesn't come all at once. It is rather the superposition of thousands of changes in the river's course. Also interesting is that the sediments deposited closer to the mountains are more coarse, and as the tributary approaches the Napa River the sediments become finer and finer. The book has great illustrations of the watersheds of the tributaries and their alluvial fans.
Harvard Magazine, Jan/Feb-05: The geologist authors explain how winemakers interact or "dance" with the Napa Valley environment. The story begins millions of years ago with the clash of continental plates.