"I will never kick a rock"

Draining Glacial Lake Woodstock – June 17, 2021

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Draining Lake Woodstock

On the Rocks; The Woodstock Times 

Jan. 9, 2009

Updated by Robert and Johanna Titus

 

We closed last week’s column with a remarkable image. We took you, the readers, west on Tinker Street and then we looked up into the air and saw 280 feet of ice water above us. This was the water of Glacial Lake Woodstock, probably the most important ice age feature in the Woodstock vicinity. We found ourselves at the bottom of this lake with all that ice water above us. That is an astonishing claim.

We left ourselves with the responsibility of proving this notion and today is the day. We would like to not only prove our assertion, but also give you a good example of how we geologists see the landscape as we travel about.  We have a habit of seeing things and noticing things that other people don’t.

Mind you, we usually have to do a lot of exploring before we see these things. Let’s start out west of Bearsville which is also west of Lake Woodstock. On the map there is an interesting pass which hugs the north side of Acorn Hill. You can get there by driving up County Rte. 45, AKA the Wittenberg Road. At the top of the hill is a very inconspicuous bridge.

Bridges are supposed to cross rivers or at least creeks and there is a problem here. There is no water beneath the bridge. This is certainly a bit of a curiosity. But the problems get worse quickly. There is a bit of a valley here, a dry one. You can recognize where stream erosion has cut into bedrock and cut a small canyon. Canyon might be overstating it but there definitely used to be a good flow of water here. All this needs explanation!

We are at the far western end of Glacial Lake Woodstock. Our canyon is dry today, but back at the end of the Ice Age there was a powerful flow here. Lake Woodstock was dammed to the east by a great wall of ice, the Hudson Valley Glacier. It was a time when the climate was warming, and the glacier was melting. The waters of Lake Woodstock had to go somewhere, and it was through this canyon that they flowed. Back then these flows entered into the drainage of today’s Little Beaver Kill.

There must have been a very powerful flow of water. Imagine, all of the glaciers in the region ere melting and much of that meltwater was flowing down Little Beaver Kill. It could not have been all that “little” back then!

When we visited the site, we looked and, in our mind’s eye, we saw the ice age torrent. Today, there is no water at all; we climbed down and walked a few yards along the floor of the old stream. We felt the raging whitewater flow passing beneath us. Back then it would have been certain death to jump into this current. But, as geologists, we are lucky; we can experience the best of both worlds and both times.

Now the point of all this is that this dry canyon lies at 880 feet above sea level. The floor of the Saw Kill Valley is at just about 600 feet. The difference, 280 feet is the depth of the old lake. It was a very deep lake.

The great physicists and mathematicians of the world are often still in their 20’s. Geology is different; it is an experiential science. Its best practitioners are not young hot shots, just out of graduate school. They are, like us, the seasoned veterans who have put in decades of work and are able to recognize features in the landscapes around them. You spend a lifetime absorbing your science and then you see it all around. Believe us, we see the world differently than most.

If you get a chance, please travel up Rte. 45 and see the inconspicuous little bridge. Your mind’s eye is just as good as ours. This is your chance to go back and see the Ice Age.

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

Glacial Lake Woodstock – June 10, 2021

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A cold bath for Woodstock

The Woodstock Times; On the Rocks; Dec 11, 2008

Updated by Robert and Johanna Titus

 

We have, off and on, over the past year or so (2008-2009), been journeying through Woodstock’s ice age history. In this column we would like to slow down a little and try to focus on one of the more interesting aspects of this saga: the story of Glacial Lake Woodstock.

Lake Woodstock was first discovered during the middle 1980’s. It was described, briefly, in a State Museum report, but not much work has been done on it. To date, it has only been recognized as a relatively small lake, mostly just to the east of today’s town. It was, we think, much bigger than that. we have been poking around the area and we are now convinced that the lake stretched all the way to Bearsville. It deserves a lot more investigation than it has gotten. Let’s do some of that today.

We have, in an earlier column, claimed that most of the area west of Woodstock formed on the bottom of the lake, and if you travel west down Tinker Street and look to your left and right, you will see the old lake floor as an extensive flat landscape. But there is more, much more. In fact, this all gets to be very interesting to a geologist.

Our descriptions so far, have been of the first Lake Woodstock. There was a second one and that is where we want to take you today. That first Lake Woodstock formed when a glacier, lying just to the east of town, was damming the Saw Kill Valley. The ice dam blocked the flow of the Saw Kill and that created the lake: the first time.

The climate warmed and the glacier retreated back to the northeast and there is a good chance that the first Lake Woodstock drained off to the south. But the Ice Age was a very complex time; its climate was constantly shifting. Under such circumstances a warm period with melting can be replaced by another cold period with a re-advance of the ice. That is what happened. Take a look at the satellite shot. If you view it carefully you will see that the landscape has a streamlined look to it. That streamlining was sculpted by the re-advancing ice. You can actually “read’ the movement of the ice.  It advanced out of the Hudson Valley, from the upper right-hand side of the photo, and pushed on westward. we are not sure how far it got, but we can see streamlining at least as far as west of Bearsville. That means that much of the Saw Kill Valley was, once again, filled up with ice. In fact, when we look at this image, we can convince ourselves that the hills, south of Woodstock are smoothed off and streamlined, more than is the case for the taller Overlook Mountain, to the north. We are guessing that the ice actually overran those southern hills. It seems to have been a major advance of the ice.

We wonder how long such an event takes, but we will never know. And we wonder how long the ice remained, clogging the Saw Kill Valley. we will never know that either. But, given enough time, the climate warmed and the ice retreated from the Saw Kill, one final time. Once again, the remaining ice formed a dam, and that dam blocked the Saw Kill and created the second Glacial Lake Woodstock.

Take another good look at that satellite shot and you will see the flat landscape in the Bearsville area and again, just south of Woodstock. There is still more flat landscape in the area east of Plochman Road. All these landscapes are the floor of Glacial Lake Woodstock. It was pretty big.

One logical question is how deep was it? we alluded to that in a column earlier in the year. we believe, that in the Bearsville vicinity, this lake was at least 280 feet deep. If you are reading this somewhere near Tinker Street, we would like you to look out the window and up those 280 feet and “see” the ice water here. Once again geology has a way of rearranging your sense of reality.  Carl Sagan had something to say about notions such as this. He said that “extraordinary claims require extraordinary evidence.” Providing the evidence for the 280-foot claim will be our responsibility in the next column.

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

 

I heard that crack – June 3, 2021

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“I heard that crack!”

On the Rocks – The Woodstock Times – June 18, 2021

Updated by Robert and Johanna Titus

 

Being a scientist means that you are going to end up knowing a lot of smart people and I no exceptions to that rule. But we have only ever known a handful of geniuses. One of those is our friend, photographer Vincent Bilotta, who lives in Palenville and works throughout the Catskills. It is hard to define real genius, but you know it when you encounter it. Take a look at some of his photos and you will see.

We had, for years, been trying to take a picture of a geological feature that lies beneath the stone bridge at the top of Plattekill Clove. That’s at a gorge called Devil’s Kitchen, which is one of the most scenic parts of this very scenic clove. It’s dark down there, underneath the bridge, and we just never could get a good picture. Vincent, the genius, not only took a good photo but he produced a great one. He has kindly let me use his image to illustrate today’s column.

The feature we are speaking of is seen left of center in the photo. Take a look and see the structure that looks like a gigantic, petrified bird feather. It’s three or four feet across so don’t worry, no bird produced this. It is what structural geologists, logically enough, call a “plumose structure” and it has quite a story behind it.

The rock it is seen upon is Devonian in age; it is about 380 million years old. It is sandstone and probably its sand was deposited in the channel of a Devonian river. It hardened into rock and subsequently it became involved in one of the great mountain building events in Earth history. That would be the Acadian Orogeny, an event that produced an early version of the Appalachians, called the Acadian Mountains. The rocks we see here were involved in the uplift. They once lay deep within the bowels of those ancient mountains. There were subjected, back then, to truly intense pressures. The rocks you are looking at were, for a long time, buried under a mile or more of bedrock. Imagine the pressure that produced!

Our rocks were squeezed by all that pressure. It is difficult to imagine rocks being compressed but that really can happen. Typically, rocks have a good deal of “give” to them and they can absorb the stress, pretty well. It is much later that they encounter trouble.

The mountain building event we are talking about involved a great landmass, called Avalonia, colliding with North America. That is where the compression came from. It only got worse, later on, when also Africa collided with North America. Mountain building collisions, however, only last so long. Eventually, what happened is that the collision ended, and, in fact, a breakup of the land masses occurred. Africa drifted back to the east toward where it is today. That released all the pressure that had compressed our rocks.

In this new relaxed state of affairs these rocks began to expand back to their original state. That’s when they became brittle, and that’s when the fracturing occurred. You see, a plumose structure is a special type of crack. Essentially, the fracturing begins at the base of the “feather” and expands away from that point. As the fissuring “ripples” through the rock it creates the plumose pattern. Take a good look at the photo, or better yet, go to the bridge at Devil’s Kitchen and see the real thing. You can easily imagine the fracturing passing through the rock.

This was an exciting moment; things happened fast. Some geologists think that the fracturing occurs at something that approaches the speed of sound! And it must have made a lot of noise too; we would imagine a very loud pop or snap. The surface that the plumose structure is on is a flat, nearly vertical plane. That is another aspect of the fracturing. We call such a fracture plane a joint; it is a special type of crack.

All this amounts to another of those most remarkable features, so often found in the rocks. This was not just a little bit of deformation; this must have been a real earth thumping event. For all practical purposes this is a petrified earthquake. Think about that for a moment. You can actually preserve the evidence of an ancient earthquake in the rocks!

And photograph it.

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

 

A superpool of natural gas 5-7-21

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A superpool of gas.

On the Rocks, The Woodstock Times July 8, 2008

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. New York State geologists have long known the term, and many have visited outcroppings of the dark shale and sandstone that we call the Marcellus.

 

We have written about it occasionally in Woodstock Times columns over the years. The unit of rock has recently become very important.

 

Late last year (2007), 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 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 quarter of America the search is on. This is bound to be controversial so, before we go too far, let’s get something straight. We are geologist, 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 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. 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 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. Perhaps you would like to see the unit; it’s not far away. Take Rte. 31 south from Woodstock 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. We found a fair number of fossil shellfish. This does not seem to represent the great stagnant abyss where natural gas would accumulate. So, our guess is that the Mt. Marion will not yield much natural gas, at least not around here.

Farther down the road, near the south end of the outcrop, we found a more finely bedded sequence of black shale. It is made up of very thinly laminated seams of black shale and it displays no fossils. This, we think, is a deeper part of the old basin and it might be that these strata are richer in gas.

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. we will have more to say about the Marcellus in future columns; it may be very important geology.

Reach the authors ay randjitius@prodigy.net. Join their facebook page “thecatskillgeologist.”

Visions at Boulder Rock, May 20, 2021

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Visions of a distant past: The ledge at Boulder Rock

On the Rocks, The Woodstock Times

Robert Titus

 

Boulder rock has always been one of the most popular destinations for hikers at North/South Lake State Park. You find your way to the Catskill Mountain House site and then take the Blue Trail south and uphill into the forest. It’s a nice, not very difficult climb, and it brings you to near the top of South Mountain. Along the way there are several fine views that can be obtained from sizable bedrock ledges. At a left fork in the trail you hike downhill again and, after a short walk, there it is: Boulder Rock.

There should be a word for a bigger than usual boulder. This one is larger than even the word boulder implies; it must be ten feet tall and maybe 15 feet across. This enormous rock was brought here by an advancing glacier, quite possibly at the peak of the Ice Age. The ice advanced down the Hudson Valley, coming from the north. It had no trouble shoving forward a rock of this size. Glaciers are very powerful; they are used to pushing things around.

If we are wearing the right shoes, we can climb to the top of Boulder Rock and get a much better view. Looking south, we can see Kaaterskill Clove; looking southeast we see the southern Hudson Valley; looking east we see the Taconic Mountains and, finally; looking north we can see much more of the Hudson, stretching almost to Albany.

But it is not today’s scenery that captivates us; it is an image from the distant past. We geologists are like that. When we are standing atop Boulder Rock, we can transport ourselves into the past of some 14,000 years ago. we stand upon the boulder again, but now in a different moment of time, and before us lies the Hudson Valley as it was during the latter stages of the Ice Age. We have arrived here just a few minutes before dawn on a cloudy day. The cloud cover is thin and so a lot of defused sunlight manages to penetrate it. This Ice Age Hudson Valley is cloudy but well lit.

The climate has, in recent times, warmed considerably and the glacier has begun vacating the valley. But there is still a lot of ice out there. An enormous glacier had once been advancing down the Hudson and, at its peak, it had risen up well above the Boulder Rock ledge. In fact, it had overridden all of South Mountain, and North Point too. But recent centuries have seen it melting away.

Still, the valley remains almost filled with ice. The glacier is almost 2,000 feet thick out there, just a short distance to the east. And, stretching beyond that, the ice reaches all the way to the Taconic Mountains on the other side of the valley, a distance of many miles. Those mountains rise above the glacier. They lack much in the way of color. They can only muster a darker shade of gray, enough to contrast with the glacier. The ice is also gray, but mostly a lighter tint of that dull “color.” As it has melted away, soot has been brought to the surface to discolor it.

The surface of the glacier is irregular; here and there we can see shallow pools of water. These never get very big; they always find a way to drain down into the ice below. The bottom of the glacier cannot be seen, but it is very wet down there. The glacier is broken by great fissures; these originally formed as crevasses, back when the ice was still advancing to the south. The brittle ice could not stand the strain of movement and it gave way and fractured. But that was long ago; now the old cracks have lost their once sharp edges. These have gradually melted away. Warming climates have taken a toll. The glacier has an aged look to it.

Time passes and the rising sun has broken through the thin cloud cover and now sunshine radiates across the entire vista. As the sun continues its ascent, the ledge all around basks in its warmth. Even in these cold times the sun can warm things up. Some of that radiation is reflected downwards. That is probably why there is a great gap between the boulder rock ledge and the ice below it. Sunshine has melted away the nearby ice to open up this yawning chasm. The hours pass by and soon it is midday. Now it can be seen that the sunlight is shining directly into the gap and its walls of ice have become shiny with fresh meltwater.

But this day will last no longer than any other; the sun continues its inevitable traverse off to the west. Near the end of the afternoon, it disappears into another bank of clouds, much thicker this time. Now the weather changes quickly; it grows windy and cold. Soon a heavy snowfall begins. By early evening, a thin bank of snow has drifted up against the western side of Boulder Rock.

Past midnight the skies clear, the winds die down, and it grows truly frigid. The stars are bright, even in this night’s full moon. For long hours before the next day’s dawn, the Hudson Valley is illuminated in the moon’s spooky silvery light. Cold, silent and dead, it is a wondrous sight to behold.

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

 

Stream Piracy in Kaaterskill Clove

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Piracy in the Catskills

On the Rocks – The Woodstock Times

Updated by Robert and Johanna Titus

 

Kaaterskill Clove attracts thousands of people every year just to enjoy the scenery. They hike and climb along the clove trails. They visit the waterfalls. They walk up the canyon. On it goes, there are so many recreational things to do here. The clove is well known regionally, and you might not expect this location to be known internationally, but it is. But when we say internationally, we should be a little bit careful about what we imply. You see, the clove’s international fame is within the world’s geological community. Kaaterskill Clove became geologically famous about a century ago when something special was discovered about its landscape. This, it turns out, is just about the best place anywhere to go and see something called stream piracy.

Stream piracy must sound like a most unlikely term. Try to imagine a river with an eye patch, a sword, a parrot on its shoulder and a Jolly Roger flag; it doesn’t work. If you prefer, we can mention other terms we use, like beheaded stream or barbed drainage, but neither of them does much good in explaining itself. Clearly, we need some definition here. Take a good look at a map of the drainage in the Kaaterskill Clove vicinity. There is something most peculiar. Gooseberry Creek, which flows west from the clove area, is not part of the clove. Instead, it begins in Haines Falls and flows into Schoharie Creek. Lake Creek, which does form the head of Kaaterskill Creek has a peculiar pattern. It begins at South Lake and flows westward, as if to join the Schoharie Creek system. But instead, it makes a very sharp turn, tumbles off of Kaaterskill Falls and then enters the clove drainage.

All this is very strange looking on a map. Lake Creek and its tributary, Spruce Creek look like they should be part of the Schoharie drainage, indeed they should be the head of that river system, but they are not. They have been diverted eastward and flow into Kaaterskill Creek. (see heavy black line) Thus, it makes sense to say that the Schoharie system has been “beheaded.” The confluence of Lake and Kaaterskill Creeks is at a very sharp angle: That is called “barbed drainage” and that term does make sense. But why and how did all this happen? That’s where the term stream piracy is needed.

Stream piracy was described here about a century ago by N.H. Darton. He noticed that Kaaterskill Creek flowed down a very steep slope. With all of the momentum that the water developed, it was no surprise that the creek was highly erosive. Its erosion has created the rugged and picturesque landscape that we see here and enjoy so much. That’s a beauty that the members of the old Hudson Valley school of art referred to as “sublime.” But the Schoharie Creek system, including Gooseberry Creek, is not on a steep slope, and it is not very rapid or erosive. Its valley is nice to look at, but it isn’t very rugged, and it is not “sublime.”

The stream piracy, we see here, began at the end of the ice age. Kaaterskill Creek began attacking the steep slopes of the eastern Catskills that had been left by the erosion of the Hudson Valley glacier. As it gouged its canyon into the Catskills, it encountered the upper reaches of the Schoharie Creek drainage. Kaaterskill Creek cut right into that system and has diverted some of the drainage and turned old Schoharie tributaries eastward into its own canyon. The diversions are seen at the sharp turns in the streams, the barbs in the drainage. This is stream piracy, and it will continue. In the future more of the upper Schoharie will be lost to a greedy and expanding Kaaterskill Creek.

The process will continue on into the future until our steep Catskill Front is eroded back into a gentle slope. It will lose most of its majesty in the process but there is little cause for alarm. This will not happen for many millions of years.

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

The old mountain turnpike Ar. 29, 2021

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The Old Mountain Turnpike

On the Rocks – The Woodstock Times

Updated by Robert and Johanna Titus

 

One of our region’s most historic roads is also one of its least known. It’s the Old Mountain Turnpike. Long ago, the road was the gateway to the Catskills. As far back as the 1820’s guests of the famed Catskill Mountain House Hotel took carriages up the pike to get to the hotel. As the hotel prospered, so did the turnpike. When the hotel got even more successful, it built the Otis Elevated Railway right up the Catskill Front, and the old dirt road slowly fell into disuse. Today the once great turnpike is just a horse and hiking trail, but it still has much of its 19th Century atmosphere. It makes a nice walk in the woods and, of course, along the way there are many rocks.

To get to the Old Mountain Turnpike take Rte. 23A into Palenville. Turn onto Bogart Road and head north to Mountain Turnpike Road where you turn left, the trailhead is at the western end of the road. You can hike all the way up to North Lake State Park if you like, or any part of the way. You don’t have to go far however before you are in the thick of the geology. The road climbs, makes a bend, and then a fine outcropping of reddish rocks appears. This is great Catskill Delta of the Devonian age. Such red strata are old floodplain deposits, silts and clays left by ancient floods and hardened into red shales. The darker deposits are the muds of delta backswamps. Away from the river channels, swamps formed in low-lying areas and those dark muds accumulated. Watch for fossil plant fragments in all of this.

As you continue up the road you will encounter, at frequent intervals, a number of sandstone ledges. They are Devonian river channel deposits, composed mostly of sandy strata that dip one way or another. These are called cross beds and they are the products of ancient river currents. The river currents drove masses of sand into large “dunes” which migrated downstream. Most of those cross beds dip to the northwest as that was the direction that the old rivers flowed. In between the sandstone ledges the road tends to be pink or red. These are hidden floodplain deposits. The pattern is clear: river sands are followed by red floodplain shales and then more river sands and so on. The Catskill Front is like a great building, it’s made up of sandstone and shale “stories.” When we make such a hike, we almost always count those stories.

The second story had some prominent ripple marks in a layer of red shale that crossed the road. The ripples record breezes that blew across a shallow delta pond and generated currents that, in turn, created the ripples. Incredibly those ripples are the record of breezes of nearly 400 million years ago.

At the fourth story we found a vertical ledge of sandstone that had been scoured and striated by a passing glacier. This event occurred a mere 20,000 years ago. A twinkling of time compared to the age of the rocks themselves.

 

The 14th story was a massive sandstone. This must have been a very large river. Such rivers were what are called delta distributaries. In a large delta complex the trunk stream splits up into many such distributaries. Each one meanders back and forth across the delta plain. A river that is here today, may be gone tomorrow, replaced by a floodplain. That’s why these river sandstones alternate with red floodplain shales. Look at a map of the Mississippi Delta and you will see good examples of such distributaries. Then look at a map of the Ganges River Delta of Bangladesh and you will see even better examples.

 

The road ascended into a place called Sleepy Hollow and then made a sharp left bend. Here had once stood the Rip Van Winkle House; it had been the halfway stop for carriages headed up to the hotel. The hollow was naturally air conditioned with cool mountain breezed descending through it. It must have been a nice place to stop. But what impressed us most was just above, one of the largest, thickest stories of the hike. We thought that this must have been one of the greatest rivers of the Catskill Delta.

The 24th story brought us to a great overlook. The trees have been cleared away here and a picnic table set up. We ended our journey and sat and gazed out at the Hudson Valley. We had seen enough history for one day. We had watched as 24 Devonian rivers and one glacier had crossed this location. History is complex.

 

 

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

 

Geologist.”

The Claverack Giant Apr. 22, 2021

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The Claverack Giant

The Columbia County Independent

Dec. 20, 2002

Updated by Robert and Johanna Titus

IN RECENT DECADES there has been a small flurry of discoveries of ice age elephants in New York State. You may well have read about the mastodont discovered in Hyde Park; it made quite a stir down there. The bones were found quite by accident in a swampy section of family’s backyard. All they had wanted was to dig a small pond, what they got was an ice age treasure. Researchers from the Paleontological Research Association in Ithaca spent the summer excavating the skeleton and most of it was recovered. Such events are very exciting, and people come from all over to see the bones as they emerge from the muds. Some even got involved in the project, there is never a shortage of local volunteers to help out in such a dig.

Less well known was a similar discovery near Ithaca. Another swampy area yielded the bones of an ice age elephant. This one was a woolly mammoth, and this dig attracted dozens of Cornell students. A big surprise awaited them when, during the excavation, the remains of a second skeleton, this one being another mastodon, came to light. You can imagine the excitement that accompanied this “twofer.”

Such discoveries are always big news stories in the local area. They should be; they are rare and exciting events. But, during the eighteenth and nineteenth centuries very many more such discoveries were made. In those times it was common for farmers to drain their swamplands and this frequently led to the discovery of large bones. The Hudson Valley of New York State became something of a world capital for mastodonts, as these close relatives of the modern elephants were apparently very common here, especially in Orange County in the lower Hudson Valley.

Our story begins in Columbia County. Columbia County is the site of the first discovery of that ice age emblem, the mastodon. This historic event dates back all the way to the year 1705 when a Dutch colonist came across a fossil tooth on the banks of the Hudson River at the town of Claverack, just north of the city of Hudson. The name of our discoverer seems to have been lost to history. It’s a shame as this was, without doubt, the most historic thing that he ever did. The tooth certainly was remarkable. Most of the root had decayed away but the enamel still gleamed. And it was big, weighing in at 4 and three quarters lbs. Evidently, our colonial discoverer thought little enough of it however, as he sold the tooth to assemblyman Peter Van Bruggen for a gill of rum. Van Bruggen brought the tooth to Albany where Edward Hyde, Viscount of Cornbury and governor of the New York Colony, obtained it. Cornbury is most famous for supposedly dressing in women’s clothing, but that is another story altogether. He showed a more scientific side to his nature with his interest in the tooth; he wondered what exactly it represented.

Cornbury wouldn’t keep the specimen to himself; he sent it off to England’s foremost scientific organization, the Royal Society in London. In the letter he sent with it Cornbury reflected upon the various ideas that had been proposed to explain the wondrous fossil. There were two hypotheses: some people thought the tooth to have come from some remarkable beast or fish. Cornbury doubted that; he thought the tooth was human, the remains of an ancient giant.

Cornbury lived long ago in a culture very different from ours. We know what a mastodon is, as we are geologists. You very likely know what a mastodon is as they are very well known to members of our modern culture. All of us are very comfortable with the idea of prehistoric creatures, as we have seen them in the museums, on TV, and in the movies. But, back then nobody, absolutely nobody, had ever even imagined such an animal as a mastodon. Not only had no one ever heard of such a prehistoric monster, but nobody had ever heard of prehistory. That notion would have been quite an unwelcome revelation to Cornbury. He thought, like almost all westerners, that the world was only about six thousand years old, the direct creation, at that time, of God.

So, if there was no prehistory and if there were no prehistoric monsters, then what exactly did Cornbury believe the creature to be? When he used the term “giant” he was referring to the Bible quote “there were giants in those dayes.” To his credit, Cornbury sent men to search the Claverack site for more evidence, and they were successful, sort of. Cornbury’s crew did locate the skeleton and made efforts to dig it up, but the bones were so decayed that they largely disintegrated as the came to the surface. They did estimate the skeleton was 30 feet long. And perhaps, they thought, it had been much bigger than that; a limb bone was found and, before it too disintegrated, it was estimated to have been 17 feet long. A halo of discolored earth surrounded the skeleton, and that was 75 feet long.

Lord Cornbury’s view that this was a biblical giant was enthusiastically embraced by the prominent Puritan minister Cotton Mather, of Witch Trial fame. Mather had once studied to be a physician and had a strong interest in natural history. He, like many ministers of his time, believed that an understanding of nature would confirm the Old Testament account of Earth history. The sediments in which the Claverack giant had been found had been deposited, Mather thought, by the Great Deluge. These views may seem quaint today, but in the 18th century this was legitimate science. The teeth and bones were, Mather argued, the remains of an Antediluvial giant and he wanted to prove that. At that time, he was working on a book to be entitled “Biblia Americana” and in it would be the latest scientific evidence for the Creation and the Deluge. The Claverack giant was important science to Cotton Mather.

But there were other opinions. From the very beginning, in 1705, there were people who had referred to the Claverack teeth as being like the ivory of an “Olivant,” using an old spelling for elephant. The skeleton was not that of a human giant but one of nature’s giants. This was still a very theological view, as the poor creature would have been regarded as having been also a victim of the Deluge. And it must have been quite a flood to have swept a tropical animal so far from its natural setting.

The debate was a long one, and it was not finally settled until a good skeleton turned. Now we have lots of them.

 

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

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The Killer Trees

On the Rocks/The Woodstock Times, 2000

Updated by Robert and Johanna Titus

 

Contrary to the stereotype, most scientists have rich imaginations, and we often like to indulge in wild speculations about our fields of research. Most of the time these ideas can be quickly proven wrong, but sometimes we get an off-the-wall idea that is not so easily eliminated, in fact it may start to look pretty good.

Recently (in 2000) an interesting new hypothesis has been introduced that may offer us a chance to better understand the black shales and dark sandstones of the Catskill sequence. The dark appearance of these strata makes them remarkably eye-catching and they loom, dark and menacing, over the landscapes wherever they are exposed. The best local area is along Rt. 209, just south of the Saw Kill.

 

Black stratified rocks are often rich in undecayed organic matter; it’s the black of the carbon gives these rocks their color. This generally suggests to the geologist that there were low-oxygen conditions in the sea waters at the time of deposition. Without oxygen, most decay bacteria cannot function, and they soon die. But why low oxygen? That’s where that new hypothesis comes in.

That new idea is sometimes called the “killer tree hypothesis.” Although the term may seem a little too extravagant, it probably isn’t that far off the mark. The story starts during the middle Devonian when the evolution of land plants was really starting to accelerate. By then land plants had been around for quite some time, but they had only managed to evolve into small forms with thin, weak stems. Nothing that could be called a tree had yet appeared. Trees require wood as support tissue. Not surprisingly, when wood did evolve, large, tall land plants soon followed, and the world’s first forests quickly appeared.

So what do trees on land have to do with black colored shales in the ocean? Quite a bit, it turns out. Wood had much to do with our story because it allowed trees to grow so tall that they required deep root systems and that’s when we return to the black shale and the poison sea. Complex root systems help to break up bedrock and they greatly accelerate the rate at which bedrock is weathered into soils. Not surprisingly, deep, well developed soils appeared in the Devonian, possibly for first time in history. This was a major transformation of the landscape. Barren landscapes with thin soils were soon replaced by lush foliage and thick soils as our world’s landscapes turned green and blossomed with plants that grew in deep soils.

All of this led to far more rapid rates of deposition in nearby oceans. Thick soils were easily eroded and provided sediments that glutted nearby streams. The sediments were eventually transported into the nearest ocean which was the Catskill Sea. All of this material was rich in dissolved nutrients, materials such as nitrates and phosphates. When these nutrient rich sediments entered the Catskill Sea, they fertilized the water and that led to the next step in what was now a complex chain of events.

The newly fertilized oceans were ideal for algae; they experienced what is called “algal blooms.” Great population explosions of algae occurred in the shallow, surface waters of the Catskill Sea. While all this was great for the algae it was tragic for just about every other category of marine organisms. As the algae died, they were attacked by decay bacteria. The decay process consumed so much oxygen that the seas soon became oxygen-depleted. With the loss of oxygen, bacteria had in effect poisoned their own habitat. Because they needed oxygen too, their numbers soon plummeted and very soon, all types of animals suffocated in the oxygen depleted sea as well. But the algae just kept on proliferating in the surface waters where there was plenty of oxygen, diffusing in from the air. Soon, large masses of undecayed algal material sank to the floor of the ocean. Almost none of this biological matter ever decayed, consequently the sediments that are found there are very rich in black organic carbon. These would eventually harden into thinly laminated, black shales.

When this happens today in a closed body of water, we refer to it as eutrophication. The Catskill Sea was largely isolated from other deep bodies of water.

All of these conditions promoted what are called thermally-stratified and stagnant waters. The surface layer was hot while, at depths, the lower strata of water remained cool. Dense mats of floating plants and animals grew upon the warm surface waters. Depth stratification and a dense planktonic mat prevented agitation and mixing of the waters, causing stagnant sea floor conditions to develop.

Soon a deep basin with a black mud bottom, devoid of life, appeared. Virtually nothing could live in this sea, except at the surface where there was always plenty of oxygen.

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

Drumlins along the Hudson April 8, 2021

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Drumlins Along the Hudson

On the Rocks – The Woodstock Times

July 23, 1998

Updated by Robert and Johanna Titus

 

The Hudson River is curious in at least one respect, it doesn’t have a proper floodplain. Much of the Hudson Valley is flat as a floodplain is supposed to be and you can go and see this. Cross the Kingston-Rhinebeck bridge and drive around north of Red Hook. Take Rt. 9 or 9G and you will cover a lot of flat landscape. But it isn’t a floodplain. Floodplains are supposed to be just barely above the level of the river, but this landscape is elevated far above the river, often about 200 feet up. If that flat surface isn’t a floodplain, it must be something else. It’s the floor of Lake Albany, the great lake that flooded the Hudson Valley after the last glaciation. Lake bottoms are composed of flat-lying masses of silt and clay and that is exactly what you are driving across.

But not all of this landscape is perfectly flat. There are a number of hills in the Hudson Valley. Let’s learn about some of them. Take Rte. 103 North of the Bard College Campus and turn right (east) onto Rte. 79. That road will take you into a cluster of small hills which break the smoothness of the old lake bottom. There are nearly a dozen of them and all of them are elongate in a north-south orientation. Most hills are composed of bedrock, but these are mostly sand and gravel with a fair number of boulders mixed in. Most of them are perceptibly steeper on their north slopes. That gives them the appearance of an upside-down spoon bowl. With so much pattern here, there must be a geological story and, of course, there is.

Drumlin field    Drumlin

The hills are called “drumlins” and they are a product of the closing phases of the ice age. There are differences in opinion as to exactly how drumlins form. One idea is that the moving ice sculpts glacial sediments that were already there, smoothing heaps of sand and gravel into the sinuous curves we see. A second opinion holds that the advancing glaciers encountered bedrock obstructions and reacted by depositing heaps of sand and gravel. Then those heaps were sculpted into the shapes we see today. In either event the drumlin is apparently produced directly by the moving ice and everybody agrees that they formed at the bottom of passing glaciers. They always tell us which way the ice was moving; the steep slope is always the upstream end.

Two drumlins, see symmetry and shape.

There are never just one or a few drumlins; they come in large numbers, arrayed in drumlin fields. Sometimes there are thousands of them, but in our location, there are only a dozen or so. From Rte. 79 turn left onto Guski Road and head north. Soon you will pass between two fine drumlins. Unfortunately, they are forested, and it is hard to get a good sense of what you are looking at. At 0.9 miles up the road you can turn around and look back at the steep “upstream” end of the western-most of the two. Here, at least, you get a good look at a drumlin. If you continue north on Guski Road you will pass through the valley between two more drumlins and then reach Rte. 78. Drumlins, when they are not covered by trees, are quite striking landscape features to look at. We were hoping to be able to tell you where to get a good look at one, but by the time we reached this point, we were getting discouraged. Luck intervened, however, and we finally did find a good one. Head east on Rte. 78 a half mile and look back. There is a very small drumlin here, but it does have very nice shape and it is not covered with trees.

So how did these drumlins form? The Hudson Valley glacier seems ro have been readvancing across the floor of Lake Albany. Was the lake still filled with ice water at the time? We don’t know. we need to do more field work, but we suspect that the glacier encountered a number of bedrock obstructions here and was forced to dump its load of sediment into the hills we see. We are not exactly sure how these drumlins formed, but maybe it doesn’t matter much; these dozen nondescript hills, none of them more than 200 feet high, have quite a story to tell, if you just know how to read it.

Before you head back home, you might explore the roads a little to the east. Follow Rte. 78 to Rte. 9 and then head south until you return west on Pitcher Lane. Notice all of the flat landscape you are crossing. You are on the bottom of Lake Albany, under about 90 feet of ice water, or at least you would have been at the close of the ice age.

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

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