When Georneys announced that June’s Accretionary Wedge Global Carnival was “What’s your favorite geology word?” I knew that this would be the perfect launching post for this blog. As a physical geographer, an ice-age ecologist, and a frustrated English major, I have a lot of favorite geoscience words (where else do you get to say words like “drumlin,” “foraminifera,” and “roche moutonnée”?). If I had to pick just one, however, I’d have to go with gyttja, the fine-grained, nutrient-rich organic mud that accumulates at the bottom of lakes and bogs.
“Gyttja,” pronounced “yit-chah,” is a Swedish word; some of the pioneers in Quaternary studies have come from Sweden, but I’m guessing the real reason the word stuck with English-speakers is because it, like “loess,” is so fun to say. I’m sure some would argue that it’s not a proper geology word — I’ve heard more than one hard-rock geologist refer to my research material as the “late-Cenozoic overburden.” Some Quaternary scientists dismiss the term as not terribly informative (these are often the type that painstakingly match mud colors to a Munsell chart; to each their own).
But I love gyttja– I love spending long summer days on a floating platform the size of a picnic table, bringing up meter after meter of sediment core from the bottoms of the small kettle lakes that are my field sites. I love watching the sediment transition from dark, organic-rich mud to the lighter silts and dense grey clays as the core segments get deeper– essentially time traveling via mud, as roughly a thousand years of time are captured in each meter. I’ve even eaten gyttja (a rough field test for the presence silt is to put a bit on the tip of your tongue and feel for grit against your teeth).
Most of all, I love bringing gyttja back to the lab to reveal the microscopic material preserved within, dissolving and sieving away the silts, clays, and organic material to find the pollen, charcoal, and other paleoenvironmental proxies my lab uses to reconstruct the environments of the past. My parents and friends don’t always understand what I do as a grad student, but they’re not terribly surprised that I still play in the mud.