We want to tell you something about the popular science writing business. Sometimes you, the writer, can get in way over your head. That’s going to happen this week. That it may sound bad but’s not only confined to popular writing; it’s common in professional research too, very common. So, it’s something that we should admit too and see how it is dealt with. In recent weeks we have been exploring the 65-acre landscape of the Willows, an old farm site south of Athens. We knew that we needed to run a column about the sediments of Glacial Lake Albany that underlay all of the farm and its fertile soils. So, we were on the lookout for exposures of that sediment. We commonly noticed that many stretches of the trails had been footworn down into those sediments. See our first photo. That shows a trail that exposed light-colored, uniformly fine-grained silts and clays without any pebbles or cobbles. We immediately recognized them as lake deposits, just exactly as we had expected.
But worn-out trails do not constitute good geological exposures; we needed something better. At last, we climbed down to the steep slope at the north headland of that pocket beach we talked about recently. And there it was, an exposure of lake sediment about six feet (Oops! This is science – two meters high). It was again all silty clay lake sediment. See our second photo. We were pretty happy about all that - until we started thinking about it. How many times have we said it: “The hardest thing to see in science is that which is not there.” You see all up and down the Hudson, wherever you see the sediments of Lake Albany, they are beautifully stratified. Every winter the old lake froze over and very dark clays settled to the bottom, forming a black stratum. Every summer, the ice melted, the lake currents were stirred up, and light colored, silty, sometimes sandy strata formed. Over time, light and dark strata alternated as something we call glacial varves – but not here. We didn’t notice that at first, but there it was. We couldn’t find any stratifications; it all seemed to be one very thick and continuous summer varve. Our Lake Albany strata seemed to have been deposited during one very improbably long summer. We had a problem.
So, that gets us back to where we started this column. That’s where we found ourselves in well over our heads. How are we going to explain this? As of right now – we can’t. We are pretty well educated and experienced scientists, but we have a mystery here. That happens in all sciences. What do we do? Yep, we ask for help. We know that there is a good sprinkling of PhD geologists who read our columns. Do any of you have a good hypothesis?
Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”
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