October 15th is a date of some importance for us who live in the eastern Catskills. That’s when a number of the parking lots along Rte. 23A in Kaaterskill Clove re-open to the public. If you enjoy exploring the clove, then this is the time. We always have; we can’t even remember our first visit; it was so long ago. But so too do many of our talented friends. That includes Athena Billias, a well-known Catskills landscape artist. Recently Athena showed us a painting that she did in the lower part of the clove – a location called the Red Chasm. Take a look at our illustration.
We always like to say that the Red Chasm is called that for two reasons: it is red, and it is a chasm! Athena caught both of these. Both deserve to be described and explained in a geology column. Let’s do that red color first. This is something that is explained by the mineralogy. The strata in this sequence are rich in the mineral hematite which is an iron oxide with the chemical formula of Fe2O3. That composition is reflective of its origins. These rocks were, originally, sediments deposited on dry land surfaces. There was plenty of oxygen and that combined with iron, making the resulting mineral and also the rock blood red. That’s sort of what the word hematite means (blood-ite; get it?). Well, as far back as our very first Mountain Eagle column (in 2017) we have been describing all the sedimentary rocks, here in the Catskills, as having been deposited on the lands of a great river delta, called the Catskill Delta, so, all in all, this story rings true. There is not a geologist in the whole world who does not immediately think of ancient dry lands as soon as he or she sees red sedimentary rocks.
So how come there is a chasm here? That all has to do, once again, with that environment of deposition. We found ourselves on that ancient delta’s landscape. These red strata are almost all composed largely of silts and clays. Way back in the Devonian time period, roughly 385 million years ago, these deposits were soils on that delta. You may have heard of Georgia red clays. Those are modern warm climate soils and that, essentially, is what we had right here – so long ago. Ours were probably truly tropical.
These red strata have only limited amounts of quartz sand in them, so they do not put up much of a fight when strong currents of water are trying to erode them. That was the case about 12,000 to 14,000 years ago when the final melting of ice age glaciers was well underway. Violent torrents of meltwater were cascading down the canyon right here. These flows were cutting into all those soft rocks like a hot knife cuts into butter. That’s makes for a rather dramatic origin of the chasm.
If you ever get the chance, we hope you will visit the Red Chasm. Stand at its very bottom, turn and face upstream. Travel into the past and see, hear and then feel the overwhelming power of these torrents as they pass across you – and through you. This is something that even the best landscape artist cannot quite capture. But you have been given a mind’s eye, the uniquely human imagination. Now is the moment, here is the place, this is precisely what the mind’s eye is for.
Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”
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