A horse, a glacier and the evolution of our Christmas trees: part one
Are you sitting next to a window? If so, then look out at the world of today. Remember that this tiny spot on the surface of our globe was here 100 million years ago. If you could travel that far back in time then you could see the same location, but you would see a very different landscape, one typical of its time. That was your neighborhood’s Cretaceous time period and there would have been very few modern looking plants or animals to be seen. Instead, there may well have been dinosaurs. A billion years ago? You could do the same. You would be visiting the Proterozoic times. Your neighborhood had no plants or animals at all; back then, there was nothing more advanced than microbes. If you could go back 4.6 billion years then you would be watching the formation of our planet, an extremely different image. A gigantic dust cloud was coalescing into a primitive planet, right in front of you. Look out that window again; a lot of geological history has passed by out there.
Our column has commonly tried to do this sort of time travel. We never get tired of thinking these thoughts and writing these words. We pondered this recently after having been invited by CarolAnn Corbett of Freehold to see her property. She had found some geology that she thought we would be interested in. We arrived and CarolAnn led us to a pasture ruled over by a horse named Camanche. See our first photo. CarolAnn led us to several small outcrops in the far distance. See one of them in our second photo. Our journey into the past had begun.
We looked down at the first outcrop and quickly traveled about 14,000 years into the past. Look at our second photo again. The surface was covered with evidence. The most striking features were glacial striations. These had been carved into the rock by cobbles being dragged to the southwest by an advancing glacier. Back then the southwest was a common direction taken by moving ice that had recently risen out of the Hudson Valley. In between those striations the rock had been polished by abundant sand, lying beneath the ice.
Now we rose up, turned around and began to understand Camanche’s pasture. We noticed, for the first time, the rolling nature of that field. The gentle ups and downs defined what geologists call kames and kettles. The rising kames and the falling kettles are common ice age features. All this was sediment that had been bulldozed here by that moving ice and deposited upon that striated bedrock.
We had not actually gone anywhere, but we had traveled – backwards through time. We looked around again and saw no horses, nor any pastureland. Instead, we had become witnesses to an ice age landscape. All before us was barren earth. Masses of bare sand and gravel rose and fell in gentle sinuous curves. To the northeast was a glacier with heaps of earth all along its front. It didn’t seem to be moving but it made all sorts of cracking and groaning sounds. There was motion out there.
But our journey was not over; we would go back to that outcrop and travel hundreds of millions of years farther into the past. That’s next week.
Contact the authors at randjtitus@prodigy.net Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”
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