I don’t know how true this is for all departments, but Vanderbilt’s Earth and Environmental Sciences cohort contained a substantial number of the cheerfully insane kind of people who spend their weekends scurrying up cliffs like so many clumsy geckos. I’ll gladly admit to being one of them. We would joke that a prerequisite for graduation would be climbing on all the rock types – sedimentary (Middle Tennessee for limestone, and the Red River Gorge for sandstone), metamorphic (gneiss in North Carolina), and igneous (some lucky classmates got to climb Devil’s Tower in Wyoming). Climbing up a cliff face gives a geologist a kinetic, tactile perspective on our theoretical specialties. We grumble at the soft limestone polished by fingers and rain, rough up our hands climbing brittle fractures, and rejoice in the hardened holds created by iron-rich inclusions.
My sister, being awesome and knowing me so very well, gave me a book for Christmas that combines my two passions: “Flakes, Jugs, and Splitters: a Rock Climber’s Guide to Geology” by Sarah Garlick.
Although “Flakes, Jugs, and Splitters” give a good overview of basic geologic concepts, it’s not an intro to geology textbook. It’s guided by an interest in the history of specific landscapes, and the geologic concepts are fragmented enough by that location-based treatment that someone with no geologic background would not be able to get a good overall view of processes. I skipped over the sections explaining basic plate tectonics in favor of looking up the back-stories of all my favorite haunts and dream destinations.
Garlick divides her book up by region; focusing mainly on North America, she also has sections for each of the other continents. Within the region, each section is headed by a question that I can easily imagine the average climber asking (well, because I’ve asked them too), and then dives into the geologic story behind it. As geologist who has studied in the southeast, the upper Midwest and Yellowstone area, and California, I really enjoyed the sections on the geologic history of the Southwest and Northeast. How could I have had no idea that the Rio Grande follows a rift zone? The mysterious dark extrusions I saw in Arizona while driving cross-country make much more sense now!
The author also manages to surprise me on my home turf; she gives one of the clearest explanations of the formation of the Appalachians that I’ve ever seen, complete with elegant, non-technical diagrams. It’s so fantastic that I went to the trouble of scanning it in to show my online tutoring students.
The tone of the book stays light and conversational, which makes it a pleasant read to flip through. The book is understandably skewed towards popular American rock-climbing destinations. Some areas are explored in depth, such as Colorado with nineteen pages, while Africa, Asia, Australia, and New Zealand get nineteen pages between the four of them.
My favorite rocks features for climbing, as explained by Sarah Garlick:
- Knobby bits of rock called “chicken heads” – formed by “case hardening” where the outer surface becomes more resistant than the inside, either by the outside being reinforced with salts (desert varnish) or by the interior being weathered (limestones and poorly-cemented sandstones)
- Pockets (a.k.a. “jugs) – these delightful features are often caused by cavernous weathering where salts crystallized in nooks and crannies in the rock, displacing adjacent grains in the process. The salts then weather more easily than the surrounding rock, leaving behind places for me to hang easily after dealing with too many @#%$ crimps.
The book definitely earns an A+ for excellent use of clear diagrams and epic climbing photos. It’s visually appealing, well laid out, and easy to read. I would love to see USGS geologic maps for the climb sites, but that might be too geeky for this book’s pay grade. I’ll just have to look those up myself. I’m being greedy – this book gives a very good bird’s-eye view of geology across the USA.
Overall, this book is an awesome light read for its intended audience – scientifically curious practitioners of “dynamic vertical yoga and risk-assessment”. If I knew a teenager or undergraduate obsessed with rock climbing, I would give them this book in a heartbeat to lure them into geology.