Robert Titus - page 24

The Mountain House Ledge

The Catskill Geologists

Robert and Johanna Titus

We always like to say that there is a spiritual heart to the Catskill Mountains and that heart is a field called Pine Orchard, lying atop the Catskill Front near North-South Lake Campground. There is a fine ledge of sandstone there and it offers a 75-mile sweeping view of the Hudson Valley. Not surprisingly it became the site of a hotel and that was the famous Catskill Mountain House, first opened in 1824. We frequently find ourselves visiting and we like to sit upon that ledge and gaze into the valley below. Behind us is the image of the old hotel, crowded with its many guests. Back in the 19^th Century anyone who was anyone stayed in the hotel. Three presidents visited along the most prominent businessmen, industrialists, artists, writers and so many other celebrities of those times. Now the hotel is gone, but its presence can still be felt here; it was an important place; it still is.

We put our hands upon that sandstone bedrock; it is important too. Human history fills the empty space above the ground but everything below the surface is geological history, and that’s all ours. We can touch it and we can see it. There are miles of sedimentary rock beneath the surface right here and that is a lot of history. That sandstone ledge, for example, is a petrified river deposit. Those sandstones were once sands and they filled a sizable river channel, flowing from out of New England and into the west.

That river flowed across something called the Catskill Delta. It’s an ancient bit of history, well-known and perhaps even well-loved by geologists, and it conjures up quite a story. We look east and see the profile of a rising mountain range out there. Those are the Acadian Mountains and we are looking about 380 million years into the past. Those mountains are in their prime and are very actively rising. They are also actively weathering. Chemical processes are destroying the bedrock of those mountains, turning it into sediment, mostly sand, which is traveling down mountain streams. Where those streams are entering the Catskill Sea, which lies west of the mountains, they are depositing the Catskill Delta.

And, at the Mountain House site, we are sitting in the middle of just one of those streams. It’s not unusual for hundreds of them to make up a large delta complex. But suddenly we realize something important about this river: in its day, it must have been lying exactly at sea level. Such deltas always form at sea level. We, again, gaze into the valley below. The Hudson River flows at today’s sea level and that lies about 2,200 feet below us. Suddenly we have an “aha” moment. This ancient river had once flowed by at a level 2,200 feet lower than where it is today. It has been uplifted all that much. There has to be a story here, a story of tectonic uplift. Let’s continue with this next week.

Contact the authors at randjtitus@prodiy.net. Join their facebook page “The Catskill Geologist.”  Read their blogs at “thecatskillgeologists.com.”

The Abyss at Olana

Robert and Johanna Titus

The great tourist attraction in the middle Hudson Valley is Olana. We went there and stood on the bank in front of the south-facing porch of the old mansion and gazed at its fine view of the Hudson Valley and Catskill Mountain. This is one of the great vantage points from which to see the Catskills. There are days when the atmospheric conditions are just right, and the mountains seem to reach out to you. It’s not just a view; this is also a genuine work of art. Frederic Church intended the porch should have this vista; it is, among many others, one of his “planned views.” For thirty year he was able to enjoy the scene and we envy him that.

But as geologists, we are privileged to see some other views at Olana. On that wonderful site our minds drifted back into deep time. We were at the bottom of the oceanic abyss that was once here. The waters were cold and black, but more than anything else they were still and silent. This was a dead seafloor. Nothing crawled across the mud and nothing swam in the waters. We scooped up some of the mud; it was soft and sticky. It was foul with the remains of dead microbes that constantly rained in from above.

With time the avalanches came. The stillness was abruptly interrupted as the seafloor was jolted by seismic shocks. Shortly thereafter great masses of sediment began tumbling down the slopes. For long minutes there was the rush of dirty water. The torrent boiled as murky clouds billowed upwards all around us. Then the current slowed and gradually the water cleared. The Olana seafloor returned to it silent dead, stillness.

Our mind’s eyes rose through tens of thousand of feet of quiet water until they reached the surface of the sea. We gazed eastward and saw dense black clouds rising above the horizon. The blackness drifted my way and soon it rained volcanic dust into the water all around. Then we looked back eastward again and now a rising landmass had replaced the black clouds on the horizon. The stark profile of volcanic mountains defined this new horizon

The passage of time accelerated. As we watched, this landmass grew taller and its shores swelled out toward us. We were soon lifted out of the sea by the rising gray crust. Occasional, the earth beneath us shook with powerful quakes as the land rose higher and higher. Eventually, we found our imaginary selves high atop a still rising Taconic Mountain range. To the north and south, volcanoes erupted in violent spasms. Below, to the west, what was left of that deep sea retreated away from the rising mountains.

There should have been a great deal of green in this image but there was none. This was a fine range of mountains, but it was a dead landscape that had replaced a dead seafloor. We were in the Late Ordovician time period, and life, especially plants, had not yet managed to colonize the lands. All around us was a bleak, blue-gray landscape. There were not even proper soils, just a litter of gray gravel lying upon bare rocks. Only the dry channels of gullies and ravines broke the monotony of the desolation.

We realized that we had come to the very spot where, 450 million year later, Frederic Church would stand. But we were not seeing what he would see. No, below us and stretching off to the west, a large river delta had formed adjacent to the rising Taconic Mountains. A complex of murky streams crossed the dark gray of that delta. Farther away we could see the retreating waters of the sea. It was bleak and lifeless vista, but there was grandeur in this, Olana’s great unplanned. view.

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

Hit by a speeding Glacier II

On the Rocks, The Woodstock times

March 27, 1997

Updated by Robert and Johanna Titus

Around here late winter drags into spring. We get teased by a day or two of warmth and then back comes the cold. It’s depressing and takes its toll on people. But imagine for a moment being teased by some warm weather only to have to face another few centuries of cold. It happened.

Last time we saw the great Hudson Valley glacier advancing from the north, turning into the Woodstock-Ashokan vicinity and flooding the lower Esopus Creek valley. This is sometimes called the Wagon Wheel ice margin and it occurred about 17,000 years ago. That state of affairs lasted for quite some time, maybe centuries. But all bad things must come to an end, and eventually the Arctic cold gave up some of its grip. The ice began to melt, and the glacier retreated from the Esopus. The front of the ice retreated to a line that extended from just south of Overlook Mountain to just north of Kingston. This is quite a time in the history of Woodstock as it conjures up a fine geological scenario. Once again, it’s the mind’s eye that can take us to see an ancient wonder.

It is 16,000 years ago. In our mind’s eyes we are over Boiceville, drifting down the lower Esopus Creek Valley. The valley is a complete mess. It has just emerged from beneath melting ice and is strewn with glacial debris left behind. You know what your backyard looks like in April after a thick snow has melted; this is worse. To the north, behind us, glacial ice is still rapidly melting and that’s feeding enormous amounts of meltwater into the valley. Immediately below us, the Esopus is a swollen white-water stream. Its churning, swirling torrents are cascading down the valley. There are some stretches of the valley which are choked by enormous mounds of sand and gravel, deposits left by the recently retreating ice. These are blocking the valley and small lakes have formed behind the dams. In other locations the valley floor is covered by relatively flat plains of sand. There the Esopus has spread out across the sand and its channel has split up into a myriad of small crisscrossing streams. Geologists called them “braided” streams.

We continue our mind’s journey and leave the Esopus at Ashokan and head northeast toward Woodstock. Below, the landscape continues to be a desolate mess, more heaps of glacial sediment alternating with many small ponds. There are no trees as the climate is still too cold. As we continue drifting eastward, we begin to see a number of much larger pools of water. Beyond them the Hudson Valley glacier rises. The front of the glacier runs north-south right through the present-day location of Woodstock. The front of the ice is very low and behind the front the ice rises at a very low angle. Advancing glaciers loom tall and menacing in a valley, but the low slope of the ice we see is the hallmark of a melting glacier. All along the front of the glacier large springs of dirty meltwater are welling up into those pools of water. From time to time masses of ice collapse into these pools. These are noisy affairs and large waves radiate across the ponds.

All this should be a hopeful sign. There were no people in North America to witness this melting but had there been there would have been grand rejoicing at the retreat of the great ice sheets. Glaciers had filled the lower Hudson valley for the last 5,000 years. Now this awful glaciation seemed about to end.

But sadly, all good things come to an end. Earth history seems to be an endless number of cyclical events. Alas at 16,000 years ago conditions once again shifted in favor of the glaciers. “Spring” would be delayed a few centuries as there was another advance of ice into the Esopus Creek valley. This one is called the Rosendale readvance of the ice and it repeated much of the Wagon Wheel event. Once again, a glacier passed across Woodstock and once again it crossed today’s Ashokan Reservoir. But this time the advance was not quite as far. Once again, the cyclical sequence was repeated. The ice advanced as far as it would and then stagnated. Still one more time the cycle, predictably, swung back from cold to less cold. That favored melting and the glacier retreated the Woodstock area, this time for good. Is “for good” as long as forever? Not likely, but the glaciers have left for good, at least in the way humans measure time.

Oh, the indignity of it all. In effect a glacier ran across Woodstock about 17,000 years ago. Then, a thousand years later, the ice stopped, backed up and ran across Woodstock a second time. Nature means no offence to Woodstock; her endless cycles are just her way.

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

Laurels for a Great Big Rock

On the Rocks; The Woodstock Times

June 4, 1998

Updated by Robert and Johanna Titus

June is the time to visit North Lake State Park. If you have not been there, North Lake is one of the gems of the New York State park system. There’s not one, but two gorgeous lakes (The other one?  . . .South Lake, of course). More than that, there are several miles of trails running along the great Catskill escarpment. Anywhere along the escarpment trail you can see a grand view of about 70 miles of the Hudson Valley. Beyond that, there are more trails into the woods and up into the mountains.

If you don’t like hiking then you can camp, swim, or picnic.

The park has recently opened for the new season (1998) and among the real draws is the Mountain-laurel which is, right now, in flower. But, year-round, scenery has always been the major attraction at North Lake. Thomas Cole came here in the 1820’s and the canvases he did here helped found the Hudson Valley school of art. The Catskill Mountain House Hotel was, for quite some time, the premier summer resort of America. It was right above the two lakes.

But our main attraction at North Lake has been the rocks and there are some very good ones here. Let’s go look at one of the best. Enter the park (they charge admission by the carload) and drive all the way to North Lake itself and park. Hike south toward the Catskill Mountain House site (follow signs for the hotel site and the blue trail). The hotel is long gone, but the site is still a clear field with a great cliff and magnificent view. You can see the Hudson River and the Taconic Mountains beyond. If you know where to look, you can see the town of Catskill, Frederick Church’s mansion, Olana, and many other sites of the Hudson Valley.

The hotel was pretty expensive so enjoy the view; a century ago you probably couldn’t afford it! Find the signs for the blue trail and follow them up the hill. You will ascend a couple of hundred feet in elevation, and quite steeply at first. Eventually the trail will level out upon one of those great ledges that are so typical of the Catskill Front. Here and there, you will find more vantage points. In June, however, it is the Mountain-laurel that you may want to see; they are at their best now. Soon the trail branches. Follow the signs and take the left branch toward “Boulder Rock.” It isn’t far.

It’s an odd name, but a good one; Boulder Rock is an enormous rock. You can’t miss it; it’s just to the left of the trail. What’s perhaps most remarkable about it is that it is perched right on the edge of the cliff. Yawning out before the boulder is a steep 2,000-foot drop. And if it had been any smaller it would have been pushed over the edge. Alf Evers records that virtually all such boulders, that were small enough and close enough to the edge, did meet such a fate. But this one is much too big for even a small army of very brawny men to dislocate.

So fine, now we know why it is still there, but how did such a boulder get there in the first place? The answer is easy, and it is a good one. Boulder Rock is called by geologists a “glacial erratic.” Our story takes us back about 14,000 years ago to when the last glacier was advancing down the Hudson Valley. The ice age was ending, but ice was still active in the valley. Glaciers are currents of moving ice and they can pick up and move almost anything they want to, including very large boulders. Boulder Rock was swept up in the flow of ice and carried here. The ice then melted and left the boulder behind.

This is commonplace; many displaced boulders are found throughout glaciated regions. We call them erratics because their lithologies do not match the local bedrock. Boulder Rock isn’t all that erratic, however, it probably came from North Mountain, only a few miles away.

Please do make the trip, especially if you have not been to the park before. When you reach Boulder Rock try to imagine it as it was long ago. Imagine the valley before you filled with old gray ice. The ice is melting and wet with pools of water. Up here, water is pouring off the ice and Boulder Rock itself is just emerging from its white shroud. All around, the landscape is still pretty bleak. It will be quite a while before this area recovers from its glaciation, but when it does recover, it will have done it very well indeed.

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

The Abyss at Olana

Robert and Johanna Titus

But the real tourist attraction in the area is Olana. We stood on the bank in front of the south-facing porch of the old mansion and gazed at its fine view of the Hudson Valley and Catskill Mountain. This is one of the great vantage points from which to see the Catskills. There are days when the atmospheric conditions are just right, and the mountains seem to reach out to you. It’s not just a view; this is also a genuine work of art. Frederic Church intended the porch should have this vista; it is, among many others, one of his “planned views.” For thirty year he was able to enjoy the scene and we envy him that.

But as geologists, we are privileged to see some other views at Olana. On that wonderful site our minds drifted back into deep time. We were at the bottom of the abyss that was once here. The waters were cold and black, but more than anything else they were still and silent. This was a dead seafloor. Nothing crawled across the mud and nothing swam in the waters. We scooped up some of the mud; it was soft and sticky. It was foul with the remains of dead microbes that constantly rained in from above.

With time the avalanches came. The stillness was abruptly interrupted as the seafloor was jolted by seismic shocks. Shortly thereafter great masses of sediment began tumbling down the slopes. For long minutes there was the rush of dirty water. The torrent boiled as murky clouds billowed upwards all around us. Then the current slowed and gradually the water cleared. The Olana seafloor returned to it silent dead, stillness.

Our mind’s eyes rose through tens of thousand of feet of quiet water until they reached the surface of the sea. We gazed eastward and saw dense black clouds rising above the horizon. The blackness drifted my way and soon it rained volcanic dust into the water all around. Then we looked back eastward again and now a rising landmass had replaced the black clouds on the horizon. The stark profile of volcanic mountains defined this new horizon

The passage of time accelerated. As we watched, this landmass grew taller and its shores swelled out toward us. We were soon lifted out of the sea by the rising gray crust. Occasional, the earth beneath us shook with powerful quakes as the land rose higher and higher. Eventually, we found our imaginary selves high atop a still rising Taconic Mountain range. To the north and south, volcanoes erupted in violent spasms. Below, to the west, what was left of that deep sea retreated away from the rising mountains.

There should have been a great deal of green in this image but there was none. This was a fine range of mountains, but it was a dead landscape that had replaced a dead seafloor. We were in the Late Ordovician time period, and life, especially plants, had not yet managed to colonize the lands. All around us was a bleak, blue-gray landscape. There were not even proper soils, just a litter of gray gravel lying upon bare rocks. Only the dry channels of gullies and ravines broke the monotony of the desolation.

We realized that we had come to the very spot where, 450 million year later, Frederic Church would stand. But we were not seeing what he would see. No, below us and stretching off to the west, a large river delta had formed adjacent to the rising Taconic Mountains. A complex of murky streams crossed the dark gray of that delta. Farther away we could see the retreating waters of the sea. It was bleak and lifeless vista, but there was grandeur in this, Olana’s great unplanned. view.

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

Fossil corals of the Catskill Mountains
Robert and Johanna Titus
From chapter 7 of their book The Catskills, A geologic Guide, 4th edition

Corals: Film and still photos of coral reefs portray some of the most vivid and colorful images of today’s seas. Such images are difficult to associate with the Catskills but, as in today’s tropical seas, corals were sometimes quite common in the old Appalachian Basin. While there is nothing in the Catskills that can match the Great Barrier Reef of Australia, there were some fairly decent reefs in those times. Many of the Devonian forms were horn corals (see right figure below; (A) horn coral; B) digitate corals C) honeycomb corals. Courtesy of the New York State Museum) so named because they had skeletons shaped like a cow’s horn, wide and open at one end and curving to a point at the other.
The chamber within was divided into compartments by walls much the way you see in a cut open orange. Other types are called digitate corals (figure 7-2B), that is they grew long slender branches similar to fingers (the digits). A third common group, the honeycomb corals, grew massive honeycomb-like skeletons (figure 7-2C) that are similar to some modern-day corals. Corals are only occasionally found throughout the strata of the Appalachian Basin, but they can sometimes be common in the Onondaga Limestone.

Stromatoporoids: The stromatoporoid is a peculiar fossil (left figure above), intermediate in appearance between sponges and corals. They were colonial- and reef-building animals, much like the corals. But they seem to have been simpler creatures, like the sponges. They appear to be entirely extinct, so we know nothing of their soft anatomy, and we will thus never be exactly sure what they were. They grew abundantly in the very shallow, nearshore environments of the Manlius Limestone and are seen within that unit, especially to the east as at John Boyd Thacher State Park (see Chapter Three). We have seen them in blocks of the Manlius that make up the Bronck homestead in Coxsackie.

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

National Fossil Day
Windows Through Time
Robert and Johanna Titus
Register Star – Oct. 2014

It’s coming up on National Fossil Day once again, and we have put it onto our calendar as something worth observing. But what will be we do to celebrate? We haven’t decided. We can’t put up a Fossil Day tree or carve a fossil pumpkin. We don’t really know what you are supposed to. Maybe we should just go out and do some fossil hunting. It’s, after all, a very nice season to get out and do such things. One of us, Robert, was trained as a professional paleontologist, so he has spent a lot of time doing just that, so, why not this year? National Fossil Day, 2014, is Wednesday, October 15th. It has been organized by the National Park Service in association with the American Geosciences Institute.
Last year we wrote a column about a very common fossil, a shellfish called a brachiopod. It was a form named Mucrospirifer (lower left in our picture) and it is very commonly found in our local Devonian aged sandstones and shales. Brachiopods, like clams, have two shells, but brachiopods are not mollusks; they belong to a very different group of invertebrate animals. Some species of brachiopods still live in our oceans, but they are quite rare. Back during the Devonian, however, they were enormously commonplace seafloor dwellers.

This year, let’s describe a wholly different type of Devonian animal – the trilobite.
Trilobites belong to a major group of invertebrates called the phylum arthropoda or simply the arthropods. Those are invertebrates that have external skeletons and jointed legs (actually “appendages”). We can‘t think of a better living example of an arthropod than the lobster. They possess very well-developed external skeletons and wonderful jointed appendages.
So too did the trilobites. Their external skeletons were divided up into three lobes – one running down their centers and two lateral lobes as well. That describes their backs, but underneath there was a long series of jointed legs. At the front end was a head which also had three lobes. They are not likely to have been terribly intelligent, but they did have something of a brain in the center of their heads. At the tail end of a trilobite was, of course, a tail! It also had three lobes, but it usually came to a pointed end.
Trilobites lived on sea floors. They date back to the early Cambrian time period which was more than half a billion years ago. They were very humble creatures; often they were scavengers, living by finding things to eat that were just lying on the bottom of the ocean. They were numerically important seafloor dwellers back then. In fact, whenever a geologist thinks about the Cambrian, it is likely with an image of trilobite. Trilobites were important bottom dwellers for several hundred million years, but they never surpassed their Cambrian success. They endured a long very slow and progressive decline. As the eons passed by, they just became less common and less diverse. Their final chapter came at the close of the Permian time period. That was about a quarter of a billion years ago.
Their final extinction is considered the event that brought the Permian Period to an end. We have to think that there was a final day, and a final hour, and a last minute, when the absolutely last trilobite experienced its final heartbeat. At that solemn moment, a great group of animals had disappeared. Extinction is, after all, forever.
But they remain, sort of. They are all dead but their fossils still can be found. Trilobites are among the most coveted and treasured fossil finds that a collector can hope to bring home from a day of hunting. Good ones are, however, very scarce. They had jointed skeletons, and, after death, the processes of decay caused those skeletons to disaggregate and fall apart. Because of that it is not very common for collectors to happen upon a complete and fully articulated skeleton. The two of us have only found a few of them.

The one that we have chosen to illustrate is called Phacops rana. It is named that because paleontologists have decided that it closely resembles a type of frog call Rana. It is a beautiful trilobite and it has been found here in our part of New York State. It was native to the Helderberg Sea and is sometimes, but not commonly, found in the Helderberg Limestone. That’s the unit of rock that makes up the great ledge at John Boyd Thacher State Park. It is the same limestone that you see along Rte. 23 at the large outcrop just west of Catskill. Can you go and find one for yourself? That is VERY unlikely.

Have you found a good fossil trilobite? Send us a picture at randjtitus@prodigy.net. Join our facebook page “The Catskill Geologist.”

Crinoids in the Catskills
From: The Catskills: a geologic Guide. 4th edition, Chap. 7
By Robert and Johanna Titus

Crinoids: Another living but largely unknown group of organisms found in the Catskills are the crinoids, also known by their common name, the sea lilies (figure 7-13; Drawing of a full crinoid, courtesy of the New York State Museum.- see below). Sea lilies are most remarkable animals. They commonly have five arms and that clearly indicates their relationship to the starfish. Although five arms may be an odd trait for an animal, what makes them truly unusual are their stems; they are stemmed animals! At the base of their stems are root-like structures called holdfasts, which tether them to the sea floor. Again, they are animals, but their plant-like morphology is what gives them their common name. Sea lilies grew in “meadows;” dense populations of them swayed in the currents much as meadow grass sways in the breeze. Today’s crinoids are brightly multicolored, and this adds to their plant-like image. They are especially common in the Coeymans and Becraft Limestones, although they are rarely well preserved. Look for abundant scattered stem remains.

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

  7-13 – Typical crinoid, courtesy NY State Museum

  Living crinoid.

  7-14 – Limestone ledge, rich in crinoids

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.”