Poet and novelist Gertrude Stein is famously quoted as saying “there is no there there.” People have been pondering and debating exactly what she meant for decades. We wonder if the two of us be remembered for the following quote: “There is no here here” That should, on the face of it, be equally ambiguous but, unlike Gertrude Stein, we are scientists, and we are going to explain ourselves clearly . . . we hope.
We would like it if you caught one of our outdoors acts sometime. We do geology walks all over the Catskills and the Hudson Valley. It’s late in the season right now so we have nothing coming up soon. But watch our facebook page “The Catskill Geologist” where we list our upcoming events. It’s almost always the case that Robert dramatically sticks out his right arm and points as he turns a full 360 degrees. He goes on to proclaim how this spot is a tiny dot on the surface of the globe, but it has been here for 4 1/2 billion years. It’s been so different in the past and more so in the far distant past. Then the two of us go on to show the evidence for what that spot was like during the Ordovician, Silurian, Devonian or the Ice Age. We take our participants back to “here” as it was back then.
But there’s a problem” where exactly was “here” back then? You might think we are being silly. After all, how could here have ever been anywhere else? That’s what generations of geographers and philosophers have thought, and anybody can understand why. But, beginning in the 1960’s, those views changed. You see, there are a number of rocks which have small crystalline grains in them that contain iron. At the time of formation, it is possible or even likely that those tiny bits of rock will settle into an orientation aligned with the magnetic north and south poles. One end of the crystal points toward the north pole; the other points south.
Once settled into place those magnetic grains should sit where they are - forever. Right? They should always point north and south - forever. Right? Well, you can imagine how surprised mineralogist and sedimentologist were when they discovered that they don’t do that - at all. And the older the rock was, then the farther off-target those magnetic grains were. They had discovered a pattern and that was something that needed to be explained.
One hypothesis was that the magnetic poles had been moving. That would be a simple solution, but it’s widely understood that poles can’t and don’t move except for just a little bit of routine wandering. Magnetic and geographic poles are and have always been closely aligned. The moving pole hypotheses had been quickly falsified. That left only one other, an almost disturbing hypothesis: it was the continents that had moved!
Geologists had commonly speculated that “continental drift” had long been moving them around on the surface of the globe, but most dismissed the idea as being wildly improbable. Suddenly it was not only probable, but it had been demonstrated! Well, that gets us back to where is here. We now understand that here - the Catskills - had long ago been there – somewhere south of the equator. Many geologists think that today’s here was located about 20 degrees south of the equator during the Devonian, back when most of our local rocks were forming. That’s southeastern Laurentia on our map, courtesy of Wikimedia Commons. That kind of rearranges your sense of reality, doesn’t it? Science is supposed to do that.
Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”
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