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The Catskills: mountains or a plateau?
The Catskill Geologists
The Mountain Eagle
Robert and Johanna Titus

One of us, Robert, once suddenly began receiving hordes of emails from the students of an eighth grade middle school class. Each message claimed that he, Robert, had made a bad blunder in referring to the Catskills as being mountains. Each of them “corrected” Robert by pointing out that the Catskills are actually a “dissected upland plateau.” Their teacher had assigned them to do this. He wanted to know how Robert would respond to having been shown to be in error. Needless to say, this was annoying. It is, however, a commonly held notion that the Catskills are, on the basis of some narrow technicalities, not a range of mountains, but a plateau that has been lifted and then eroded, or dissected, by numerous streams, hence a dissected plateau. Let’s deal with all this in today’s column.
English is a wonderful language, well suited to describe the distinctions between all sorts of ethereal concepts. Typically, it is possible to use a choice of several words to describe the same thing. The words mountain and plateau are examples. The two terms grade into each other, but are defined in the Glossary of Geology, published by the American Geophysical Society (AGI). These are thus as close to official as such definitions can get, and they give plenty of guidance and also considerable leeway in using the two words.
The AGI definition describes mountains as being, first of all, taller than hills, usually rising more than 1,000 feet above surrounding lands. Equally important, mountains have restricted summits. They have steep slopes and considerable exposed bedrock. Perhaps most importantly, they are distinctive enough to have individual names. That last point is subjective, but critical.
Plateaus do not have restricted summits; they are “comparatively” flat areas “of great extent and elevation.” A plateau’s “flat and nearly smooth surface” can be “dissected by deep valleys or canyons.” But in the end, it must have a “large part of its total surface at or near the summit level.” When we look at maps of the Catskills, we think that the valleys are so broad, and the summits so restricted that they just do not conform to the notion of a plateau.
The Catskills are composed entirely of nearly horizontal sedimentary rocks and some think that this makes them a plateau. But the AGI definition does not prohibit flat-lying strata within mountains. Nor does it does it require them in plateaus. Those horizontal strata date back to the origins of the Catskills as a great flat-topped delta.
We travel the Catskill Mountains and see so many distinctive summits. Slide Mountain meets all the standards required to be a true and distinctive mountain. So do North and South Mountains, Overlook Mountain, Windham High Peak and so many others.
When there are a number of such mountains, the AGI glossary specifies that they can be combined under a proper name heading, such as the Adirondack Mountains.
But, beyond all of the above, there is an issue of elegance. English should, as often as possible, be an elegant language. Its words should flow off the tongue smoothly, they should also read the same way. We ask you: did Rip Van Winkle sleep for 20 years in a dissected upland plateau or in the Catskill Mountains?
Climb to the top of Slide Mountain someday this summer. Gaze out all around and decide for yourself: are you standing on top of a plateau?

Contact the authors, unless you are an eighth grade teacher, at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”

Boom town
On the Rocks
The Woodstock Times, Jan. 16,1997
Updated by Robert and Johanna Titus

Woodstock, Aug. 15, 382,439,953 BC, the predawn hours–There is, of course, no Woodstock at this time, but the land is here. It is a morass of bayous and swamps, populated by the primitive trees of the Gilboa forest. It’s the end of a moonless night and it’s still dark out, but there is a growing light and it’s not the approaching sun. Over the past several weeks there has been a slow-moving pinpoint of light in the nighttime sky. It is an asteroid, about a half mile across. It’s moving in from the south and, as it enters the thin upper atmosphere, it is starting to glow quite brightly. Its speed is about 20 miles per second, but it is still so far away that it seems to hang in the sky. As it comes closer, however, its apparent motion speeds up. Now as it enters the denser parts of the Earth’s atmosphere, friction heats it into a great flare. The whole western sky lights up, silhouetting the black horizon below.
This is the critical moment; if the asteroid is small enough and its angle of approach low enough, then it will bounce off the atmosphere and skip harmlessly back into space. If not…. The flare’s flight path doesn’t skip, it plummets silently and disappears behind the western horizon.
Moments pass in what seems to be an endless pause, and then comes a great and instantaneous shock of light. It flickers for a few seconds and then the whole northwest horizon glows red. The color brightens to an orange, then a yellow and finally a brilliant radiance of white. An enormous gassy fireball rises rapidly above the horizon to the west, followed by a rising mass of black smoke. This dark cloud rises quickly, and it gradually assumes a funnel shape.
Incredibly, this entire scene has been played out during nine seconds of complete silence, but that ends abruptly. The nearby ground begins to hiss and then roar. Great waves of earth radiate across the landscape. They are powerful surface earthquake waves which move very much like the waves of an ocean. As they pass by, geysers of watery sand erupt from the ground. All of the trees fall down; their primitive roots are unable to support them on the shaking, soft, wet ground.
In another six seconds the great atmospheric shock wave of the impact blast itself hits Woodstock. For several minutes the landscape rocks with the combined effect of the earthquake and the shock waves. Then, at two minutes after the impact, the actual sound of the asteroid’s impact catches up with the initial chaos. Only the word “unimaginable” does justice to the power that this sound signals.
Meanwhile, the great rising fireball has blown a hole in the stratosphere and it continues to rise. It’s a hundred miles high now and the trailing plume of dust below is catching the high sunlight of the still approaching dawn. The whole thing has become an awe-inspiring pillar of white, starkly outlined by the surrounding dark. The pillar is a chimney with walls of dust; its flue is a vacuum which is drawing a vast draft of air upward. Back at Woodstock things had quieted momentarily, but now a new breeze has started and it’s being sucked toward that chimney. It quickly speeds up to gale force and then to hurricane speeds. All this air is drawn up the chimney and vented out into space.
Next comes a hailstorm of dust and rocks. This is the debris that the impact blasted out of the earth and threw tens of thousands of feet up. Now it’s all falling back again. The first rocks plop loudly into the still churning muds. Then the higher-flying rocks start returning as an incredibly dense shower of blazing meteors. Hundreds of them cascade out of the sky and they light up the entire sky.
In the east the sun is about to rise, but it’s a futile effort; sunlight won’t fall again upon Woodstock for months. A great stratospheric shroud of black has been expanding ominously from the west. Along its front an enormous and continuous rage of dry lightning forms an expanding plexus of sparkles that illuminate the wrecked landscape below. Gradually, a moonless, starless black engulfs the area.
But if there is nothing to see, there is still plenty to hear and feel. The winds still howl, and more rocks continue to fall out of the sky. And the temperature has been rising alarmingly over the past hour; it is already more than 100 degrees and getting hotter. Once again light penetrates the dusty gloom, but only in the form of burning plant debris falling slowly out of the sooty black sky. To the west, closer to the impact, forests have been ignited and their burning embers have been lofted into the sky. It is a hellish sight. ++

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”

The Panther Mountain Asteroid
On the Rocks, Dec. 26, 1996
Updated by Robert and Johanna Titus

Like most geologists we spend a lot of time looking at topographic maps. The whole country has been mapped and most any camping goods store will stock the maps for its own area. They are a wealth of geography; blue lines define streams, black lines are roads, green is for forests and the little black squares are homes. We find ourselves happily poring over all of these symbols, but most of all we like the sinuous brown contour lines which define our regional landscapes. Closely spaced contours define steep slopes and cliffs, while widely spaced lines indicate flat areas, so we can literally “read” the hills and valleys. We geologists consider this sort of thing to be fun, but there is a serious side to our interest. Topographic maps often tell us where to go look for interesting geological mysteries.

And, so it was, about 40 years ago, that the late Yngvar Isachsen, of the New York State Museum, found his attention drawn to Panther Mountain. The mountain has a distinctly circular shape. That’s best displayed by the two streams that nearly encircle the peak. It’s an eye-catching pattern which shows up even better on satellite photos of the Catskills. It’s a big, beautiful, nearly perfect circle about six miles in diameter, and there’s nothing quite like it anywhere else around here.
Such observations are commonplace in science; nature presents us with strange patterns that cry out for explanation. The scientist picks up the scent and goes on the chase. But from the beginning there was nothing commonplace about the Panther Mountain circle. What could have produced it? Probably one of the first ideas which would cross a person’s mind is an asteroid impact, but such things are too good to be true. Discoveries that exciting come rarely in a career and a good scientist controls his emotions and looks for other, more mundane explanations. It never hurts to be careful about things like this.
And, for Isachsen, there were some very unexciting alternative explanations. There might have been a large mass of salt beneath Panther Mountain. Salt is buoyant and might have lifted the mountain enough to cause the circle. We find such domes of salt in western New York, but there are no salt-bearing deposits this far east. Then maybe there was a great mass of granite beneath the Panther Mountain. This too might have buoyed the mountain up a bit, but gravity studies ruled that out.
Sometimes the wildest ideas that you can think of gradually start to look better and better. As Sherlock Holmes said, “If you eliminate all that’s impossible, then whatever is left must be possible.” Thus, the asteroid hypothesis kept looking better, and there were ways to test the outlandish idea. If Panther Mountain did indeed have an asteroid crater beneath it there must be a horizon of shattered rock down there. That loose rock would cause something called a gravity anomaly; things would actually weigh just a little bit less at Panther Mountain than they should. And in fact, there was a gravity anomaly, especially on the north side of the Mountain. That suggested that an asteroid had approached from the south and plummeted into the Catskills. After the impact, the sediments that now make up the bedrock of the Catskills slowly buried the crater. But as those sediments draped across the rigid rim of the old crater, fractures formed and that softened the rock enough so that Esopus and Woodland Valley creeks could selectively carve their valleys into the ring shape we now see. So, Panther Mountain is not a crater, it’s just shaped like the crater buried beneath it.
There are a number of obvious questions. First, just how big was this asteroid? That’s hard to say and nobody knows for sure, but a half a mile across seems reasonable. When did the impact occur? That’s an easy one. The impact lies within the Catskill sedimentary sequence which means the asteroid plummeted into the Catskill Delta a little less than 400 million years ago.
The biggest question is has all this been proved? Well, not exactly. A nice case has been made that is very consistent with the asteroid hypothesis. But we scientists are cautious folk, and more work needs be done. Nevertheless, it is a marvelous example of the kinds of truly exciting discoveries scientists make and make routinely. What is more drab, at first glance, than bedrock, those dull, inert, brown and gray masses of mineral material. And yet what could be more exciting than to find that an asteroid once landed in your very own backyard, a discovery only preserved in those “dull” rocks. We live in a culture rich in the pseudo-sciences, but the real science of rocks can be far more fascinating than any of them. It gives you a different perspective on rocks, doesn’t it?

Contact the authors at randjtitus@prodiiy.net. Join their facebook page “The Catskill Geologist.”

Lake Cooperstown
The Cooperstown Geologist
Jan 14, 2009
Updated by Robert and Johanna Titus

The mouth of the Susquehanna is, of course, right here in Cooperstown. You can see much of it from the bridge on Main Street. It’s a lovely canyon and it is most remarkable to contemplate that, from this little stretch of water, the Susquehanna River begins its journey of hundreds of miles.

But there is also an ice age story to be found here. Take a good look around sometime. All along the lake’s south shore the landscape rises relatively steeply. It reaches elevations of several tens of feet or so above the level of Lake Otsego. If you think about it, the shore of the lake here, except for that one notch, would make a pretty fine dam for a much deeper and larger Lake Otsego. Such a dam is, in fact, exactly what was once here.
Lake Otsego is a gift of the Ice Age. It’s a junior partner of the more famous Finger Lakes and it formed exactly as those larger lakes formed. Roughly 14,000 years ago, give or take, the many valleys of central New York were occupied by what might be called valley glaciers. It is they that created the many finger lakes.
Go to Lakefront Park and gaze to the north. In your mind’s eye fill the valley with ice. The glacier you have formed in your imagination is a long, narrow one. From Cooperstown it stretches off to somewhere beyond the north end of the lake. This glacier, however, only extends from one side of the valley to the other.
Our mind’s eye glacier is moving south. It groans, and snaps as the brittle ice is flexed. It gouges the landscape beneath it, and that erosive process accounts for the great depths of today’s Lake Otsego. But the moving ice also carries with it a lot of coarse sediment. That stuff includes boulders, cobbles, gravel, sand, silt and clay. A lot of that sediment is concentrated at the front of the moving ice.
Our advancing glacier is dependent upon continued cold climate, but climate is fickle; it is always changing. Eventually it will warm, and the ice will begin a long retreat, melting back towards polar latitudes.
But back then the heaps of earth stretched across the entirety of the valley and served to fashion the dam we spoke of. The melting and retreating glacier produced a lot of water and most of it ended up impounded behind that dam. The dam rose to an elevation of about 50 feet above today’s lake level and naturally the lake that resulted was also 50 feet higher.
Once again gaze north from Lakefront Park. Try to judge a line 50 feet above the lake and that line will be the old shoreline. The “fossil” lake has a name; geologists called it Glacial lake Cooperstown. It was big but it wouldn’t last for long.
Nature, it seems, does not like lakes, especially big ones. The earthen dam would not last. Soon, rising lake waters would have overtopped it and begun cutting a channel. Today such a dam would last only months at most. A channel would be quickly cut, and the water would pour through it. But back then it was different. Much or most of the dam would have been frozen solid. Erosion was a very difficult and slow task. Nevertheless, over time, water pouring across the dam would eventually carve a channel and those top 50 feet of the lake would have emptied. Lake Cooperstown became Lake Otsego.
So now, you can pause on the Main Street Bridge and look south at the canyon with a real understanding of it. Once again, use your mind’s eye and fill that canyon with a powerful rush of foaming, white ice water. Turn around and look north; place a melting glacier at the north end of Lake Otsego. Now you have completed a wonderful image of Ice Age Cooperstown.
Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist .”

Ghosts at Clermont
Updated by Robert and Johanna Titus
The Columbia County Independent
May 14, 2004

Geologists knows when they are about to take a trip into our distant past. It’s just part of the job. We began one of those time travels recently when we were visiting the Livingston mansion “Clermont” on the Hudson. Just north of the visitor’s center we saw a fine honey locust tree.
The honey locust is certainly not the greatest of trees; there are bigger and prettier ones. Nevertheless, there is something very special about this species. honey locusts are “armored” with very dangerous looking spikes. These can be three or four inches long, and often they occur in mean-looking clusters. The biggest of those is found on the lower reaches of the tree’s trunk. Up above, there are plenty more strung out on the lower branches.

Brush up against this tree and you will quickly find out what they are for; they are vicious defense mechanisms. The lower branches hang down and seem to reach out with their spikes as if intending to do harm. Browsing mammals will soon find out, and long remember, the dangers of trying to eat the foliage of this tree.
But who are these spikes defending against? Your might guess the white-tailed deer, especially if you are among those who have prized shrubbery in your yard. But white-tailed deer would hardly be bothered by these spikes. They have slender snouts and they find plenty of space to pick between the spikes. No, locusts have never much worried about deer.
But, if it is not deer, then who? There are no other obvious browsers in today’s woods so why do the trees go to all that trouble of growing those nasty long spikes? Those spikes, also, had to be aimed at something a lot bigger than a deer. And a lot taller too; they reach up to about 15 feet or so above the ground. There is a real problem here; the fact is that there simply are no big creatures in today’s world that threaten our locusts.
But there were some a long time ago. Back at the end of the Ice Age the Hudson Valley did have some great herbivores which might very well have pestered our honey locusts. And they were plenty large enough too. They were the mastodons.
Modern elephants have a bad reputation for tearing up forests. They love to pull down limbs and they are perfectly capable of stripping bark off the lower trunks of trees as well. In fact, elephants can virtually create their own habitat. They destroy so many trees that they break up the forests, creating lots of meadow in between the remaining patches of trees.
That rambunctious behavior creates just exactly the right habitat for honey locusts. Locusts like broken forests, preferring to be right on the border between meadow and trees. So, it would seem that evolution had cleverly adapted the locust for life with the mastodons. These great elephants created the habitat that was just right for locusts. At the same time the spikes protected the locusts from any potential damage from the mastodons.
And there was more: the honey locust seedpods very likely appealed to the mastodons. Those seedpods hung just above the spikes; the elephants could just reach beyond the spikes, eat the pods and then deposit the seeds elsewhere within their droppings.
All in all, the mastodons and honey locusts enjoyed a very fine symbiosis. But then, abruptly, it all ended. The mastodons went extinct about 11,000 years ago. The locusts lost the elephants that had helped them so much in reproduction. They have continued to survive to this day, but surely they are not as successful as was once the case. Still, in the end, it is quite the concept to contemplate. These trees and their long spikes vigilantly wait for the elephants that will never ever come again. It is only the ghosts of mastodons that still haunt our forests.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.

The fuss across the river
Stories in Stone
The Columbia County Independent
Dec. 5, 2005
Updated by Robert and Johanna Titus

Perhaps you have heard the term “Marcellus Shale” and perhaps you have not, but you will likely be hearing about it many times in the upcoming years, especially from our western side of the Hudson. New York State geologists have long known the term and now the unit of rock has become very important.

Late last year, it was announced by several researchers that the Marcellus might well yield an enormous, absolutely gargantuan, amount of natural gas. Estimates are always just estimates but people are talking about a two-year national supply of natural gas being recoverable from the Marcellus. That’s a lot and, given the circumstances, even the greenest of you will appreciate the pressure to exploit this resource.
What can rightfully be called a “gas rush” has been triggered, and all over the northeast the search is on. This is bound to be controversial so, before we go too far, let’s get something straight. We are geologists, and one thing we do is to work to keep you from freezing to death in a cave. So, we are not necessarily opposed to all this, but let’s talk about the science of the Marcellus. There is no possible harm in you coming to understanding the geological story that lies beneath your feet.
It all started nearly 400 million years ago when something you might be tempted to call Europe collided with what eventually became North America. You probably, somewhere along the line, learned about plate tectonics. If you remember some of that, then you will understand the following: The plate collision initiated a crustal uplift which, given time, would produce a great New England mountain range called the Acadians. Our focus is on the early stages of that collision. There were mountains, but they were not yet very tall. Critically, there was also developing a nearby deep oceanic basin. At its maximum it might have been thousands of feet deep. It covered what now makes up much of the northeastern United States.
Humans have visited modern versions of such environments. In recent decades we have developed the deep-sea equipment to do so. What was once a great mystery is relatively well known today. It is not the least bit unusual for such a marine basin to be very stagnant. There are few, if any, currents that far down. The rising mountains, nearby to ours, were still so small that they supplied very little sediment to the deep, just a little silt and clay. That’s important.
Raining down from above were bits and pieces of dead organisms and this biological material came to make up a very sizable portion of the Marcellus basin’s sediment. The abyss was so stagnant that whatever oxygen that might have been there was consumed by microbes. Over long periods of time, the resulting stagnant, anoxic seafloor accumulated, thick sequences of organic rich, fine grained sediment. A lot of the biologic matter became the gas methane and that formed the bulk of the natural gas that would be coveted by humans hundreds of millions of years later.
And that is why there is so much interest in the Marcellus. There is no Marcellus on the Eastern side of the Hudson, but if you would like to see the unit; it’s not that far away. Cross the river and take Rte. 32 south, then Rte. 31 south until you reach the intersection with Rte. 209. Go another 3/4’s mile south and there you will see an enormous outcropping of black shale. This is the Mt. Marion Formation which is an eastern equivalent of the main Marcellus
If you visit this site it can be quite an experience, however, to stand along the side of a highway, listen to the traffic, and to realize that this was once the deepest part of the sea. All around you it was once a dark, quiet and cold seafloor.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”

The shallow tropical Sea
Stories in Stone

The Independent
Nov. 23, 2007
Updated by Robert and Johanna Titus

It’s the dawn of November 23, 489,007,993 BC. We are the mind’s eyes, the human imagination, and we are drifting eastward over what will someday be the City of Hudson. Down below us is a shallow tropical sea. It should have a name, but it does not. It is not easy to see the expanse of ocean below us. There is just the least bit of a mist down there, just above the water. It’s not the mist of a cool November morning; these are the mists of time and, as always, they obscure.
But there are moments when the mists part and we can see that this ocean is very shallow. There seems to be a light sandy seafloor down there. We descend and find that indeed this is the case. Now we can put a name on this ocean; it is the Potsdam Sea. We get only glimpses of that sea floor and are disappointed to not be able to see anything alive down there. There are active currents and the white quartz sand can be seen to be moving, drifting with the currents. It would seem to be something of a marine desert that we are looking at.
The Potsdam is not our goal on this day; we continue to drift lazily on a course that is just north of east. We are crossing Columbia County as it was during the Cambrian time period. It’s time to learn more about the Cambrian geography. We are the mind’s eye and we can do that very well. We rise up straight into the sky, first miles, then hundreds of miles. Now we can gaze back to the west and survey much of North America as it was back then.
We see endless shallow seas. It would seem that nearly our entire continent is submerged. Across the center of what is today Canada we can see a number of large low islands, but that is all the “landscape” that the Cambrian has given to North America. This is a time of a Greenhouse Earth climate. There are no glaciers anywhere, not even at the poles. The seas have gradually risen up across almost our entire continent. North America is far south of where it is today and it straddles the equator, hence the warmth.

As we continue on our journey east. Now it is a little later in time; we see a lighter, almost pink color on the sea below. This is a different marine setting, a shallower ocean, very hospitable to marine creatures. Its waters are rich in dissolved calcium carbonate and its faunas have used this to manufacture skeletons. This is a carbonate sea, or it might be called a limestone sea.
Florida and the Bahamas are composed of limestone; it’s the bright white rock that you see so commonly down there. The seas of the Bahamas and around Florida are limestone seas; their soft pink sands are typical of such oceans. If you have had the chance to snorkel in such waters, then you will vividly recall the green seaweeds and the colorful tropical fish. It is unforgettable.
But our visit is to the Cambrian. The sea that is now beneath us is called the Stockbridge Sea and those sediments down there will harden into something called the Stockbridge Limestone. We drop down low in the sky and approach the Stockbridge. We gaze down in hopes of seeing a rich marine ecology but are frustrated; the mists of time are thicker here; we can nearly nothing in the water. We do see the aqua color of the sea; we smell the salt and feel the tropical breezes. Occasionally we can make out the vague image of some sort of biological reef, but the image is always so obscure. It is such a shame.
We, the mind’s eyes are now moving forward through time. We travel quickly and soon we reach modern times. We are standing along Route 22 in Canaan. A fine outcropping looms above us. It is the Stockbridge Marble. It used to be limestone, but it was baked during mountain building events, and converted into marble. Baking has produced those mists of time, destroying all the fossils that might have been and blinding us from the images of the ecology that was once here. Again, it is a shame.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”

Arbor Day comes early this year
Stories in Stone
The Columbia County Independent
Robert Titus

We devoted our last column to the theory of evolution and the very old age of the Earth. The Darwin Theory has seen many successes since its publication in 1859. Recently news from our own region has given it another one. We would like to report on that today.
The story goes back almost as far as evolution. Back in the autumn of 1869 there was an awful storm which swept through the Catskills. Flooding on Schoharie Creek at the village of Gilboa, saw a lot of bank erosion and uncovered three beautiful fossil tree trunks. They were in Devonian age strata and thus were roughly 380 million years old. That was most exciting; this was the oldest fossil “forest” then known.
But this discovery left a very great mystery. Only the stumps of the trees had been found; what did the foliage look like? Nobody knew, and without foliage, nobody could tell what kind of trees they were. Geologists searched for the foliage but could not find any.
Decades passed and in the early 1920’s excavations began for the Schoharie Reservoir in the village of Gilboa. The village was razed to make way for the reservoir and people still, to this day, resent the destruction of their town. But another great scientific discovery was made. About 200 more tree stumps came to light in a quarry below the new dam. These were more of the “Gilboa trees.”
This time fossil foliage was found, but not attached to the tree trunks. Nobody could be sure that the foliage and the stumps belonged to the same trees. Winifred Goldring, the New York State Paleontologist, thought that they did, and she decided that the Gilboa trees were of a type called tree ferns. She was a fine artist. She drew a reconstruction of the trees as she thought they looked, and her picture became very well known.
But was she right? There were always nagging doubts. Decades passed by, and still nobody could find a specimen of the foliage attached to the rest of the tree. Such things are very rare. But everybody hoped that someday the great discovery would be made.

Well, we are happy, really happy, to report that the day has come. Last year, in an article published in Nature, one of the most prestigious journals of science, researchers reported the long-sought discovery. In a little quarry in the northeast Catskills and cluster of fossil tree trunks was uncovered. Two of the trunks had foliage still attached.
Take a look at the illustration. Have you ever seen a tree like this? We think not. It is a very primitive tree which is what you would expect to find in something as old as the Devonian. There is no common name for it, so we are stuck calling it by its Latin scientific name – it’s a pseudosporochnalean cladoxylopsid!
This was a very primitive tree. It didn’t have a lot of things you associate with modern trees. There were no fruits or nuts, they didn’t even have seeds. They didn’t have leaves. They had structures that would only remind you of roots; they weren’t the real things. So, what did they have? They are a long slim trunk which had no branches as you would see on modern trees. They did have that foliage. Instead of leaves they had frond-like structures which must have been green and must have photosynthesized. The foliage also displayed spore producing structures. Spores, tiny black dots, were reproductive structures.

Were they ancestral to any modern trees or even related to modern plants? Maybe, or maybe not. There is some speculation that they might have been the ancestors of ferns – or gymnosperms. But it’s just as likely that they were just a strange form of ancient tree.
But they certainly are interesting. And we can take pride that such an important form of fossil has been discovered in our Catskills. They are an interesting testimony to the enormously complex evolutionary history of life that the fossil record presents to us.

Contact the authors at randjtitus@prodigy.com Join their facebook page The Catskill Geologist.”

The bottom of the sea?
The Catskill Geologists
Robert and Johanna Titus
The Mountain Eagle – Jun 16, 2017

We recently portrayed our Catskills as being a petrified delta. That is geologically true, but it is not the full story. Our delta is called the Catskill Delta and it was a big one. Geologists compare it with today’s Ganges River Delta which makes up almost all of the nation of Bangladesh. Take a good look at a map of Asia and see how big that delta is. Then imagine a similarly sized delta right here.
Deltas grow; large amounts of sediment are always carried onto them by their rivers. As they grow they expand (or prograde) into the nearby ocean. That brings delta deposits on top of older marine sediments. That should have happened during the Devonian time period when the Catskill Delta was prograding westward. If there was a Catskill Delta then there should have been a Catskill Sea.

  Manorkill Falls

So, where was this Catskill Sea? The answer is – right here. Whatever location where you bought your copy of the Mountain Eagle was once covered by the Catskill Sea. All of where the Catskills are today was once covered by this ocean. It was not a very deep ocean but it was big, spreading across much of North America.
You can see a fine outcropping of the Catskill Sea sedimentary rocks at Manorkill
Falls. That’s right at the intersection of Rte. 990V and the Prattsville Road. A better place to go is Mine Kill falls, off of Rte. 30, within Mine Kill State Park. You can easily climb down to the bottom of the falls there and poke around, looking for fossils. Pack up the family and do just that. There is good parking and an easy trail that takes you to the falls. When you get there, we would like you to learn some basic geology.

  Brachiopods

There are two types of rock down there, black shales and dark sandstones. They are all stratified. That is they were deposited in flat layers on the bottom of the Catskill Sea. Eventually those strata hardened into the rocks we see at this picturesque park. Being that this was the bottom of a run-of-the-mill sea, it was populated by just the sorts of creatures we would expect to see on such a sea floor. Those were mostly shellfish invertebrates.
We will only describe the most common ones today. Those are called clams and brachiopods. Take a look at our photo and you will see some very typical examples. We expect that you already know what clams are. They are shellfish that possess two shells. But, so are brachiopods; the two groups might seem to be that same kinds of animals but they are not. Their planes of symmetry are different and that makes them totally unrelated. With brachiopods the planes of symmetry pass down the middle of each shell; with clams the symmetry passes between their two. We hope you can see this in our photo.

  Clams

Clams are very common today; they are many of what you find when you go shell collecting at a beach. Brachiopods were equally common back in the Devonian time period when the Catskill Sea existed. That seafloor was littered with brachiopods. And, of course, that means that Devonian shales and sandstones are often littered with them as well. Please try to get familiar with brachiopods. You will find them very frequently if you go fossil hunting in our Catskills.

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.
Watch for their new book “The Catskills in the Ice Age, 3rd edition.

Footprints of a Mountain Range
Stories in Stone  – The Columbia County Independent
Oct. 3, 2003
Updated by Robert and Johanna Titus

We normally pay so little notice of the many rock outcroppings that we pass by in our daily lives. Why should we; they are just rocks? But there is so much to see if you know what to look for. Today we would like to give you a reason to look at rocks and a good one. Columbia County is a landscape that has many geological pasts. One of them shows a history of intense mountain building. That’s curious as there are no real mountains in our area. There are the Berkshires and the Taconics, but they are mostly pretty little hills. How could there ever have been real mountains here?
But there were, and in fact Columbia County was once part of one of the world’s great mountain ranges. Let’s learn how to read the evidence. We will describe what you can see at one good location and then you can look for the same thing in the rocks where you live. Travel to the intersection of Rts. 23 and 9G. Across from the Stuart’s is a fine exposure of rock. Look for horizons of thinly laminated black shale, and thicker bedded black sandstone. All this is a unit of rock called the Normanskill Formation and it dates back about 450 million years to a time called the Ordovician time period. At first these look like nondescript rocks but there is so much more.
Let’s do the fundamentals. These rocks are stratified, and each layer is a moment in time. Back in the Ordovician this location was at was the bottom of the sea and each horizon of rock was, briefly, the sea floor. Sometimes that sea floor was mud and that accounts for the shale. Sometimes it was a sandy bottom and that now makes the sandstone. Touch any layer of rock and you are touching an ancient ocean bottom, literally. We never tire of that notion. Each stratum had its turn and then a depositional event brought a new layer of sediment and created a new sea floor. If you get a chance to scuba dive across the bottom of a sea you will see its floor and you will have the impression that this is something that is, forever and forever, permanent. But our rocks tell a different story; sea floors are ephemeral.
And sea floors are supposed to be under a lot of ocean; what is this one doing on dry land? The question gets worse when you realize that this sea floor was once at the bottom of a very deep submarine trench, perhaps 20,000 feet deep. Clearly there has, since the Ordovician, been a lot of uplift. It gets curiouser and curiouser!
Sea floors, today, are almost always flat. Look over this outcrop and you will find that none of these layers are horizontal. There is more to this story; let’s keep looking. There are four road signs here. The first is a black and white Rte. 23 sign. Just to the east are three yellow road signs; the middle one speaks of a left turn. Take a good look at the strata between the first two signs. Most of the bedding here dips steeply to the east. Clearly something has happened to these once flat-lying strata. They have been tilted. Imagine, for a moment, how much it takes to move, let alone tilt, a great mass of rock. Something very serious happened here and that something was mountain building.
And, there is still more. Halfway between the first two yellow sign look for a sequence of strata that have been sharply folded into a smiley face U. Once again, imagine the energy needed to fold rocks. Keep on walking east and notice that, between the second and third yellow signs that some of the strata have lost their eastward dip and they are nearly vertical. All in all, the rocks don’t just speak to us of folding; they speak of intense deformation.
Uplift, tilting and folding are the hallmarks of mountain building and that’s what happened here, but when? Drive down the road 2.3 miles and you will reach the intersection of Routes 23 and 9. There, on the left, is a fine exposure of gray limestone called the Manlius Limestone. These rocks are younger, about 50 million years younger. They belong to a time called the early Devonian, and that makes them a mere 400 million years old. Take a good look at the lower 20 feet of strata here. These beds are gently dipping to the east, but this deformation is very mild compared to what we saw back down the road. Here there is no folding and no extreme tilting of the rocks; they lie essentially as they were deposited in the Devonian. There has never been a time when these beds were deformed. That tells us a lot.
Obviously, mountain building deformation came after the Ordovician, because those rocks are deformed. But, also, deformation must have been before the Devonian, as those rocks are not deformed. There must have been a great mountain building event between the Ordovician and Devonian and there was. Our mountain building event is called, by geologists, the Taconic Orogeny. This event reached its peak during a time called the Silurian Period and that, of course, is the time between the Ordovician and Devonian. From this location on Rte. 23 look east and, in your mind’s eye, see the profile of the Taconic Mountains that once towered on this horizon. They probably rose 15 or 20 thousand feet into the sky and so they rivaled the Rockys and Andes of today’s world.
But they are all gone, or at least, they are nearly all gone. Only the Berkshires and the Taconics remain. The rest has slowly, and we mean very slowly, eroded away. Look around you, do you see much erosion going on? This is geology and it takes a very long time.
Our story has been about these Rte. 23 outcroppings but remember that we would like you to take what you have learned here and look at the rocks near you. Can you see folding or tilting in the rocks? If so, then you are looking at the same mountain building events. Wherever you are, look up. Above you there once were tens of thousands, of feet of mountain. Now, look at the rocks in your area again. You are looking into the very core of a great mountain range. What we call Columbia County is something that you might find 20,000 feet below the top of Mount Everest. Changes your point of view, doesn’t it?

Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”