There have been many towering achievements in the history of science. We think of Isaac Newton’s physics. Then there was Copernicus finding that the Earth was not in the center of the Universe. There was Darwin’s evolution and Salk’s polio vaccine. And on it goes. The two of us are perfectly respectable scientists, but we will never come near to matching any of these. We will, however, today pursue what we think is one of the least important discoveries in the history of science. Is that even possible? Well, read on:
A few weeks ago, we climbed to the top of North Point. We saw the petrified channel of a Devonian river. Remember? Well, after that we hiked back down the Blue Trail on our return to North Lake, as always, on the lookout for another Mountain Eagle column. And, suddenly, there it was. You never know what you are going to see when you are a geologist. Sure enough, we found a very interesting rock. See our illustration. No, that’s not one of our better photographs. The sun was shining through a tree branch and those are the shadows of its leaves all over the surface. It came out better in black and white so there you have it. It should do.
The key at the top is there for scale. Do you see all those lineations stretched out from the bottom to the top? Those are puzzling, aren’t they? They are nearly all parallel to each other so there is a pattern here. These need some explaining. We recognized them right away. We had entered into another of our many journeys into the past. Geologists call these “drag marks” and that is a very good name for them. We were looking at the bottom of another one of those fossil stream channels.
Think about it. There are currents at the bottoms of all rivers. Some are strong and fast while others are slow and weak. But there are other things down there too. The main job of a river is to carry water into the ocean. But those currents are going to sweep up a lot of things along the way. The most common of those “things” are bits and pieces of plants, especially trees. Those are mostly twigs and branches. They should have been floating, shouldn’t they? But given enough time they soak up so much water that they become waterlogged and then sink to the bottom. That’s where those currents come back into play. All those bits and pieces drift downstream with the currents. They are dragged along the stream bottom by the flows, and they carve those drag marks onto the stream channel sediments.
We wish we knew more about these objects. What exactly were they? What kind of trees did they come from? There’s a sizable drag mark on the upper right. It veered to the left as it traveled along. That doesn’t tell us much about it though, does it? What could it have been? We are just watching the bottom of an ancient stream during a few minutes of its flow. That’s very ordinary event and a very routine moment in an enormous length of time. So that’s why we are arguing that this constitutes just might be the least important discovery in the history of science, and it’s all ours!. But we take pride in that. Isn’t it odd that such mundane things can be petrified and preserved in rocks? And a few hundred million years later, there they are – lying on the surface of a flagstone along a Catskills hiking trail. Drag marks are not common, but they do turn up. The key is to have a trained eye that can spot them. Well, you have just trained your eyes!
Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.”
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