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THE CATSKILL GEOLOGISTS – ROBERT AND JOHANNA TITUS

The Mountain Eagle Nov. 29. 2019

THE TEXAS COLD

This winter’s weather news from Texas has been horrendous and we are sure you have heard about it. The temperatures went down to as low as 9 degrees overnight in the Houston area. It snowed, pipes burst, and food and water shortages resulted. The cold has been called historic and it was. We have a child and two grandchildren down there, so this was a real concern.

Why? We think there is something going on that you need to understand. What happened in Texas has occurred up here as well; it’s just that we don’t notice it so much. It all began with global warming and its effect on the jet stream. Decades ago, when global warming was still just hypothesis, that hypothesis predicted that polar regions would warm up a lot more than temperate regions. Northern Alaska would warm up a lot more than New York State. It has. The Arctic has become not nearly so much colder than lower latitudes. Importantly, the temperature boundary between Arctic and temperate climes has blurred.

That led to results that had not been anticipated; the jet stream was affected. We hope you know that the jet stream is a flow of air that undulates up and down as it continuously flows from west to east. See our diagram. This brings us a lot of our weather, especially winter storms. Historically, the jet stream has been a relatively gentle up and down undulation. See the blue dashed wavy line on our diagram. That is best developed when the contrast between cold Arctic and warmer temperate warm is sharpest.

But when the Arctic warms up the jet stream is altered. The up and down undulations become shorter and steeper; they become more pronounced. See the red solid wavy line on our diagram. Their west to east motions also slow down considerably. All this can have a dramatic effect on climate and weather. The down undulations contain the coldest air. When those jet stream undulations spread to the far south, they can bring unusual, even historically cold air into a region where that is not typical. Then because of the slow movement, that cold can stay put on a region for a prolonged period of time. That’s what has been happening to Texas this winter.

Well, these undulations pass through the Catskills too. You will hear each one described as an Arctic vortex. But, up here, we just do not see them as historic events. But this was a very serious event in Texas. We think you should be watching the jet stream diagrams on your local TV forecasts. You can also probably find a webpage that will keep you up to date on the jet stream. You may come to better understand what is happening. And that’s, after all, what our column is all about.

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

The Legend of Sleepy Hollow

The Woodstock Times – On the Rocks

Updated by Robert and Johanna Titus

For most of the 19th Century the Rip Van Winkle House stood near the top of the canyon at Sleepy Hollow. It was a restaurant and inn that served the needs of the many travelers of the Old Mountain Road. That road stretched off west from the city of Catskill and it ascended all the way up the Catskill Front and beyond into the Catskill Mountains. It was once one of the great highways of the region. Today, Rt. 23A is its only descendent, and that road climbs up Kaaterskill Clove, the old path has long ago been bypassed.

But the old highway is still there in the form of a very fine hiking trail and it’s open to horse riding as well. The Rip Van Winkle House burned down in the early part of the century, but its site is still very easy to find. Sleepy Hollow is a very typical Catskill Clove. It has a nice rocky mountain stream, and the cool, shady location is still an ideal rest for today’s recreational travelers. It’s the stream that made this location. The creek has been here since the ice age ended and the powerful erosive currents that were generated by the steep slopes have carved the canyon.

The creek here is what geologists called a misfit stream. That is the stream is much smaller than it should be in order to have carved the canyon in which it flows. Little valleys are carved by small streams and big canyons are carved by big streams. That’s the way it should be, however that’s not the way it is here. But that is not to say that there is any real mystery. Geologists encounter many misfit streams and the explanation for the bad fit is almost always involved with an ice age past.

Back at the end of the last ice age there was a very large amount of ice being melted in the face of warming climates. Not surprisingly, many streams were temporarily glutted with meltwater. Great foaming, churning whitewater streams existed where today quiet little brooks are the norm. That’s what happened here. If you climb up the canyon from the Rip Van Winkle House site, you will soon encounter an old stream channel that branches off to the right (north). It’s a fine channel, but it is dry. If you follow it and climb quite some distance, about 500 feet, nearly straight up, you will ascend to a gap in the mountain. To your right is something known as Rip’s Rock, a great picturesque ledge that reaches out into the Hudson Valley. To your left the same ledge merges with the Catskill Front. In between is the gap of which we speak. It is an old meltwater spillway.

Toward the end of the ice age there was a glacier in the Hudson Valley that banked up against the mountains right here. That glacier was melting, and water was rushing off of it. The water had to go somewhere, and it was channeled right where this dry spillway is. For a relatively brief period of time there was a great rush of water right here. All that foaming, churning, swirling water we spoke of earlier was funneled through this gap. Brief as that flow was, it was very powerful and erosive enough to produce the gap we see here.

This sort of thing is called a paleo-form. That is to say that this landscape feature is literally a fossil, or relic, of different climatic conditions in the past. This is a relic of that very brief moment in time when the ice was melting. Once carved, such a feature is very difficult to erase, today’s erosion rates are so slow.

We like the term “fossil spillway” for this feature, but some geologists like to make it a little more dramatic and they would call this a fossil waterfall. That’s an exaggeration, but it’s really not too far off the mark, there was once a very powerful flow here, close to that of a true waterfall. If you climb up and down this spillway, try to keep that in mind. Make the fossil image part of what you see here. It should not be too difficult to imagine the great fossil flow that once was here. It was ice cold, extremely fast and, more than anything else, powerful. Above it there was still a very sizable glacier. The ice was wet, gray, and dirty; it was melting so quickly that you might say it was disintegrating. But the overpowering impression you would have had here back then was the noise. This fall of the water was loud, a steady mind-numbing roar. How ironic, how wrong it is that this is called “Sleepy Hollow.”

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

Rip’s Rock

On the Rocks; The Woodstock Times

Updated by Robert and Johanna Titus

One of the nicest hikes along the front of the Catskill Mountains is the trek up the Old Mountain Turnpike. Today the turnpike is just a hiking trail, but in the 19th century it was one of the region’s most important highways. It was the dirt road that transported carriages up the Catskill Front to North Lake and into the Catskills beyond. Many of the people who made this journey were on their way the Catskill Mountain House Hotel. The trip up the mountain was a tough one, for horses and people alike, and so, not surprisingly, there was a small halfway house along the way. Coaches stopped and passengers could refresh themselves while horses rested a bit. This was the old Rip Van Winkle House.

New and better roads left the old highway obsolete and abandoned. But today you can still follow the old turnpike. From Rt. 23A in Palenville, head up Bogart Road and watch for Mountain Turnpike Road. Turn left (west) and at the end of this road is the trailhead and parking. After about a 45-minute hike you will reach a dramatic hairpin turn in the trail where it crosses a mountain stream. That’s the site of the Rip Van Winkle House, just a little bit of foundation remains.

We enjoyed this hike just for the pleasure of it, but I had some geological interest as well. On the map of this area is labeled “Rip’s Rock.” Whatever that might be, it piqued our curiosity and we wanted to find out more about it. The best topographic map we could find showed a great ledge and we wanted to find out what its geology was and maybe also answer the question of how it got there. The problem was that Rip’s Rock was a full 600 feet straight up, not quite a vertical cliff but a pretty steep incline.

Actually, there was one other problem: there are about a dozen or so smaller ledges between the Old Mountain Turnpike and the great ledge of Rip’s Rock, each one, it seemed, was determined to slow down our climb. They did, but eventually we found ourselves at the base of the last and greatest ledge, Rip’s Rock itself. It took a while, but we found a cleft in the ledge and access to the top.

Reaching the top of any great ledge is one of the great experiences of the Catskills. It’s something like rising to the surface of the sea after a deep dive. As your head emerges above the top of Rip’s ledge the whole sky opens up, especially to the east, as the panorama of the Hudson Valley appears. Below is the ravine that cuts into the mountain. Its formal name is “Rip Van Winkle Hollow.” Stony Brook, the mountain stream here, has been cutting into the Catskill Front since long before the last glaciation. In part, that’s why Rip’s Rock is here; the ledge was left behind by the erosion of that mountain stream. It’s the top or lip of the canyon.

But there is much more to the story of Rip’s Rock. We soon found the evidence that we had suspected since we first gazed upwards at the ledge. The exposed bedrock, up at the top, has been ground and polished by the passing of ice. More than anything else Rip’s Rock is a monument to the ice age. From about 22 to 14 thousand years ago there were several episodes when masses of ice passed across the ledge. The ice acted like sandpaper and ground the ledge into a smooth surface. Cobbles and boulders dragged along added gouges or striations into the surface. Also, the moving ice adhered to the bedrock and yanked loose very large blocks. This, more than anything else, left the jagged cliff that we see here.

Rip’s Rock is a feature that we have seen before in these columns. It’s called “ramp and pluck topography.” The ramp is a gentle slope ground into the top of a hill by passing rock while the pluck is the jagged front left when the ice yanked loose its large rocks. We see them in many Catskill locations. The ledge at the top of Overlook Mountain is the nearest example. So too, are the Palenville Overlook and Pratts Rock in Prattsville. We have talked about all of those in past columns.

Rip’s Rock is a great hike with a wonderful vantage point at its top. You can stand at the top and gaze out into the breadth of the Hudson Valley. But as we said, this is also a monument to the ice age. When you stand there atop the Catskills you must imagine a few thousand feet of moving ice above you. It’s the Hudson Glacier slowly moving down the Hudson Valley. In the darkness you can hear the groaning and grinding sounds punctuated by sharp cracks. Every once in a while, however, there is a truly loud crack: That is rock breaking loose as Rip’s Rock is being shaped by the ice.

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

A hike to Poet’s Ledge

Windows Through Time; The Register Star; Oct. 4, 2012

Updated by Robert and Johanna Titus

We wonder how many of you understand just how deeply philosophical we geologists can be. We tend to find ourselves drawn to some fine geological location; then we come to a pause in our rambles, and we drift, insensibly, into deep trance-like thoughts, usually involving images from the immensity of time.

Well, it happens to us–all the time. One of our favorite locations for rambling into the past is a trek to “Poet’s Ledge” in Kaaterskill Clove. If that sounds like a nice place to hike to, then you are right. It’s a gorgeous ledge of sandstone, perched near the top of the eastern end of the clove. It has a spectacular view of this spectacular chasm. You gaze west, and you take it in–in its entirety. It can become a profoundly philosophical experience, an almost dangerous one.

From up there, the clove is almost unblemished. You can see the highway that ascends it, but very little of anything else “civilized.” It’s almost pure raw wilderness from up there. We geologists gaze into the clove and see it as it developed, probably over the past 120,000 years. Much of the clove was eroded towards the end of the Wisconsin phase of the Ice Age. That was a time, between 10,000 and 18,000 years ago when the glaciers that had over-ridden the Catskills were in full retreat. They were melting away and enormous cascades of water must have been coming down the canyon of Kaaterskill Clove.

When we find ourselves at the top of Poet’s Ledge, it is impossible for us not to ponder such moments. We look up the clove and I see glaciers in the highlands. In our mind’s eye it is always an overcast day. The weather is unusually warm for the Ice Age, but this is the end of that time and warm is okay. The glaciers up there are gray on this cloudy day. They are totally disintegrating in the warmth. We always pick the day when the melting is at its all-time peak. Actually, we pick the very hour when the flow hits its maximum. When we are in a mind’s eye mood, we can do this sort of thing.

We look up the clove at that great high-elevation ice once again. Then we notice that, exactly where Haines Falls is today, there is a break in the ice. A roof has caved in right here, and we can see a massive current. It is an absolutely enormous fire hose of ice water. The flow comes from a hidden sub-glacial Kaaterskill Creek. It reached where the falls are today and then momentum carries it forward so that it could bore its way through the ice and create a great cavity. We gaze at the flow of water passing through that cavity.

Below, there is, once again, a roof of ice. Much of Kaaterskill Clove is still filled with ice. The creek is confined to a tunnel passing down the canyon beneath that ice. It is a very erosive flow of water and much of what we know as the clove today is being carved down there.

Across the clove is another flow of water. It pours off the mountaintop, just west of Indian Head. The water, up there, is visible, but it quickly disappears into another hole in the ice. There are two sub-glacial torrents in Kaaterskill Clove and now, for the first time, we notice and appreciate, and understand the terrible muffled roar that we hear.

The two sub-glacial flows form a confluence immediately below us, almost a thousand feet down. All downstream from here the roof of ice has entirely caved in. The torrent of water continues rushing down the lower canyon. Right now, the “Red Chasm” of Kaaterskill Clove is being given birth to by the powerful, raging, foaming whitewater torrents. From here echo’s a thundering roar, nothing is muffled about this sound. It deafens the ears.

This panorama from Poet’s Ledge is a horrifying scene of nature’s rawest power. The sights, the sounds, and the pounding vibrations all combine to make a jarringly terrifying scene. The pounding meltwaters are cascading, crashing, coming down the canyon with the power of a small asteroid.

And then it all ends; we have returned to the beautiful vista of today’s Poets Ledge.

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

Cold Enough for you?

The Register Star

Updated by Robert and Johanna Titus

Jan 13, 2022

Our Catskill region summers generally bring wonderful weather with dry air and cool nights. Our Catskills Autumns are spectacular with their foliage. Our winters are dreadful and once again it is that time of the year. We stoically accept the onset of another cold season and make do with the holidays as some sort of compensation. Few of us, however, know or even wonder why we must endure this annual season. Do you? Many of you might be able to give a reasonably good explanation for our winter season in terms of the Earth’s orbit about the Sun. Many, or even most, of you, however, might flub the story; it is just a little too complex for a quick, glib explanation.

But it really doesn’t matter; we are not interested in the standard astronomical explanation of winter. We would like to consider a deeper reason, in fact, the real reason it is cold out there right now, and that has little to do with the Earth’s orbit and it has a lot to do with the Catskills and their geological history. If that surprises you then read on:

Even if your astronomy is not very good, most of you can probably run through a quick description of the Greenhouse Effect, it’s one of the leading environmental fears we face today. Briefly, our world’s industries are burning fossil fuels and pumping out large quantities of carbon dioxide into the atmosphere. Carbon dioxide traps solar energy much the way the glass traps solar energy in a greenhouse. As industrial production of carbon dioxide continues, it may be that the Earth’s climate will warm up with all sorts of unfortunate side effects. Such a fate is sometimes referred to as the “Greenhouse Earth.”

But what if it were the other way around? What if the quantities of carbon dioxide were declining instead of increasing? That gets us to a term which is rarely used – the “icehouse Earth.” That’s certainly not anything that anyone has been much worried about, but it actually has happened, and that gets us back to the Catskills.

The Catskill Mountains are composed of sedimentary rocks that date back to the Devonian time period. This was a time when the world was truly a Greenhouse Earth. There was 16 times as much carbon dioxide in the atmosphere then as is today. That greenhouse effect must have been enormous. But it was not to last. Off to the east, in what is today’s New England, there was a rising mountain range – the Acadian Mountains. As their uplift continued, they reached elevations that may have rivaled those of the Himalayas. Rising mountains are subject to chemical weathering and erosion. Those processes converted Acadian mountains into sediment which, eventually, hardened into the rocks of the Catskills. What is critical here is that the processes of chemical weathering consume carbon dioxide, they take it right out of the atmosphere. As the Acadians weathered away and the sediments of the Catskill accumulated, the amounts of carbon dioxide in the atmosphere dropped dramatically, from 16 times as much as today to something closer to modern levels. This, as you might guess, resulted in a reversal of the greenhouse effect and quite a cooling of the climate. In fact, there was an early ice age at the end of the Devonian Period???

There is plenty we don’t understand about this story, but this was a turning point in Earth history. Carbon dioxide would never again be as abundant as it was during the early Devonian. It levels would rebound again during the age of the dinosaurs and those great naked monsters certainly must have enjoyed the temporary restoration of the greenhouse heat. But there simply would never again be so much carbon dioxide and the climate would slowly deteriorate, with cooling temperatures, especially during the last 60 million years. Some argue that this is what caused the extinction of the dinosaurs. There is a good argument to be made too. Winters, which probably had not been much of a problem during the early Devonian, slowly become colder and more distinct from the rest of the year. The process has continued right into our time. In reality, even if industrial pollution continues unabated, ours is still a time of an icehouse Earth. Glaciers in Antarctica and Greenland attest to that.

So, are the Catskills responsible for winter? Well, that’s a bit of a stretch, but it is fair to say that the many processes that came to produce the Catskills were all part of a climate machine that eventually created the icehouse Earth climate that we can look forward to for the next two months.

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

The depths of a lake

On The Rocks; The Woodstock Times. 2008

Updated by Robert and Johanna Titus

We geologists make observations and then we make deductions: that’s how our science works. In this light we would like to pick up where we left off the last time. In that last column we claimed that once, maybe about 14,000 years ago, all of Woodstock, extending west to Bearsville, lay at the bottom of a 280-foot-deep ice age lake. It is, logically enough, called Lake Bearsville. It has been recognized by geologists since the middle 1980’s but little research has been done on it. In the great scheme of things, Lake Bearsville is not all that important; it is one of many small lakes that formed at the end of the Ice Age. There are but limited numbers of geologists running around loose in the Hudson Valley and many other geological features are of more compelling significance. But naturally if you live in Woodstock this one is important. So, we have nominated ourselves to do the research and bring to the fore long lost images of the ancient lake. We think people around here should know something of their ice age heritage and this is as good as it gets.

Once we had determined that there had been a lake here and saw the lake bottom in the Bearsville area, we started looking for more evidence. We recognized that the lake had been formed by an icy dam. A glacier to the east, a tongue of the Hudson Valley Glacier, had blocked the flow of water in that direction. The waters of Lake Bearsville had to have escaped through some exit and it should be possible to find that egress. This kind of research is first done on a topographic map. You look at the contours and search out an old escape route for the waters. Our eyes were drawn to the top of County 46. There we saw a notch which seemed just right.

We drove up to this site and saw just exactly what we had expected to see. The notch lies near the very top of Little Beaver Kill. This is a stream which today, drains water off to the west. The notch at the top of the valley is what we geologists call a “paleoform.” It’s a landscape feature that formed in the distant past when things were different. Most streams do not have notches at their tops; they simply peter out. This notch actually used to lead into the Little Beaver Kill. Water rushed through it and on down the kill. Today, the notch is almost entirely dry; you will not see a stream flowing by at all. It looks like a stretch of valley though; we found small cliffs of bedrock which had been carved by the one-time flow of water that passed by here. That’s typical of a paleoform.

This notch is what we call a glacial spillway; it was once actively draining water out of Lake Bearsville. If you visit this site, turn to the east and, in your mind’s eye, gaze off in that direction and see the ice age lake that was once here. All along the shores you are likely to see platforms of ice extending out into the lake. The middle of the lake should be ice free, dark, and very deep. A slow current will be flowing toward you. As it approaches the notch, it is squeezed into the narrows between those two rock cliffs and picks up speed. A quiet but very powerful flow of water rushes past. There is something akin to the hum of electricity, but otherwise it really is silent.

Off to the west, the flow quickly becomes a loud chaos. A raging, foaming cascade makes up this ice age version of the kill as it pounds its way downhill. There is an enormous amount of power to all this; it is the very image of the end of the Ice Age. Glaciers are melting rapidly, hereabouts, and vast amounts of water have to drain off somewhere and they too must do it quickly.

There is nothing unique about this; all throughout the Catskills and Hudson Valley scores of similar ice age streams are, at this very moment, powerful cascades. To be on a hot air balloon, drifting across this landscape, on this day, we would see and hear all of them; it would have been unforgettable.

But none of us was on that balloon, and this image has been forgotten, until today, right here, in this column. It is the job of a geologist to resurrect the past, one chapter at a time and we have done this, our job, for today, except for one thing: we promised to explain how I knew that Lake Woodstock was 280 feet deep. Remember that the floor of the old lake lies, in Bearsville, at and elevation of 600 feet. The spillway lies at 880. You can do the math. Again, as I said the last time, when you travel west on Tinker Street, gaze up those 280 feet and see the icy lake that was once here. Geology has always been a science of discovery and this, we think, is a very good one.

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

A Woodstock Ice Age, Pt. 5; the bottom of an old lake

On the rocks – The Woodstock Times, 2008

Updated by Robert and Johanna Titus

The Comeau, and plans for its development, have generated a lot of discussion in recent months. We don’t live in Woodstock. and it is not our place to voice an opinion, but it is proper for us to describe the geologic history of those 76 acres. And there is a lot of interesting geology there. Let’s focus, today, on some of the ice age history.

If you walk the Comeau trail, almost to its western end, you will find two earthen banks along the Saw Kill. If you know what to look for, there is a lot of ice age history to be seen there. Lots of streams display earth banks; these are formed when stream channel erosion cuts into the side of the riverbank and excavates into the “dirt.” In most cases there is little of great note and even a geologist will walk by without paying much heed, but not here.

If you look carefully, you will find that the earth is layered or stratified. It’s not immediately obvious, but it’s there. Careful examination will reveal more. Some layers, or strata, are light colored and relatively thick. Others are thinner and darker. The thick light layers are made mostly of sand while the thinner strata are mostly clay. This might not sound all that important, but it speaks volumes to the geologist.

  Varves

These horizons of sediment are referred to as “varves.” They are seasonal deposits that form almost only in ice age lakes. Now we are making progress. The sediments here take us back to the end of the Ice Age. At that time, summers were just getting warm enough to melt part of the great glaciers that had filled all of the area’s valleys. The valley of the Saw Kill was emptying of its ice. But, off to the east, there was still a large glacier: the Hudson Valley glacier.

That mass of ice served to dam the lower reaches of the Saw Kill valley and the dam was responsible for something that can be called Glacial Lake Woodstock. When you drive along Tinker Street, just west of the Comeau, you will observe a lot of flat landscape. That’s the floor of the old lake. And the stratified sediments within the Comeau were deposited on that lake floor.

  Lake Woodstock, Green

During summers it got warm enough, so the ice melted off of the lake’s surface. Then wind would generate currents within the lake. Those currents swept sand out into the lake and deposited it in the form of those thick, light-colored horizons; we call then “summer varves.”

During winters the lake surface froze over, and there were virtually no currents below the ice. During that time sand could not be moved around and the only deposition that did occur was of very fine, organic rich clays. Hence the origin of the thin, dark “winter varves” that we observe along the Saw Kill.

You can explore the old lake yourself. As we said, you can drive west from the Comeau and observe a lot of flat lake bottom. Bring a map along and you can map the lake bottom and really experience the lake. Some of the flattest lake bottom lies just south of the Saw Kill, across from the Comeau. Most of Bearsville was built on the western end of the lake bottom. Pretty much everywhere south of Tinker Street and west of Woodstock was lake bottom.

An obvious question is “how deep was the lake?” There is an answer to that question, and we will develop the argument for it in a future column. But for now, let’s just say that the lake level was at 880 feet in elevation. But the lake bottom, just across from the Comeau lies at just 600 feet. You do the math; the lake was 280 feet deep!

Drive down Tinker Street and look around at the flat lake bottom; that lake was big. Then look up 280 feet into the air 280 feet; that lake was deep. You have driven down this road so many times and you never guessed this, did you? It rather rearranges your sense of reality. But that is something that knowing a geological history is likely to do from time to time.

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

A Woodstock Ice Age, Part 3: High tide

On The Rocks; The Woodstock Times, 2008

Updated by Robert and Johanna Titus

There was a time when the very concept of the Hudson Valley did not mean very much, and it was not all that long ago, at least not in the way that geologists think about time. Let’s take a plane ride back 20,000 years ago. We are the mind’s eye, the human imagination, and we can do such things. We are flying from what will someday be Woodstock to what will be Kingston. It is a clear day, and we can see all the way to the horizon in any direction that we care to look. There is virtually nothing to see.

Looking straight down, we see a pool-table flat surface of white. We drop down and fly close to the “ground” (the mind’s eye can do such things) and only a little more detail becomes apparent. Now the whiteness is broken by a few dark fractures. We are close enough to tell that it is ice that we are looking at, and now we can also see some drifts of snow. But, for all practical purposes, this is a featureless and white Arctic landscape.

We rise up high into the sky, higher than before. Off to the east the white extends to the horizon with absolutely no blemish. That horizon shows the Earth’s curvature, but it is a white curve against a very pale blue. We look north and see exactly the same vision. Then we look west and there, at last, is the one blemish to the perfectly white landscape. The peak of Slide Mountain pokes above the ice; it is an island in a sea of ice.

The sight of Slide’s peak is a welcome one, but the view quickly generates a rush of awe. Slide rises to more than 4,000 feet in elevation and only just a little bit of its summit is showing; there must be a very large amount of ice. The conclusion is inescapable: there are thousands of feet of glacier beneath us. We used the word “Arctic” but we might better have called it Antarctic. There is nothing in the modern world to match what we are seeing except the vast whiteness of Antarctica. It is this notion that inspires such awe.

Millennia from this time, scientists will recognize this as one of the great glaciations of all history, and they will name this glacier the Woodfordian Ice Sheet. More than half of the North American continent is, on this day, covered with ice. We are the mind’s eye; we rise up thousands of miles above the surface and gaze to the north. Even this high there is nothing but white curved globe as far as we can see in that direction. Once again, a rush of awe overwhelms us.

To the south we do better. We are now high up enough to see the southernmost extent of the glaciation. The ice has reached into northern New Jersey and northeastern Pennsylvania. More ice has reached as far south as Long Island. Beyond the whiteness is a barren and desolate landscape. Someday scientists will call this bleak region a tundra or a “periglacial” zone.

Now we understand why the very notion of the Hudson Valley is meaningless. All of that valley, along with the Catskill Front, is buried in the thickness of the ice we see. It gets worse: off to the east both the Taconic and the Berkshire ranges are similarly submerged in ice. That is why the horizon to the east is so flat.

We continue our ice age flight back to the north. With our mind’s eye we operate a form of radar that penetrates the ice below. We can see the Hudson Valley below and we can see the Catskill Front and the Catskill Mountains. We are the mind’s eye; we can do such things as this.

We pick out Overlook Mountain within the ice and we drop down and pass down through hundreds of feet of glacier and arrive at the very peak of the mountain. Again, the mind’s eye can do such wondrous things. We watch as the moving ice is dragged across the knob of rock, found today just north of the fire tower. Boulders and cobbles litter the bottom of the ice, and these are dragged across the bedrock. They scour that surface and also carve very prominent striations into the rock. A polished and scratched surface is soon developed.

Overlook Mountain

Now, for us, the mind’s eyes, time speeds up and we feel the climate warming. We watch, again with awe, as the Woodfordian Ice Sheet begins melting all around us. In what only seems to us as the briefest period of time the peak of Overlook emerges from the ice. Now that knob of rock is left behind; its scratched surface remaining as a testimony to what happened here during the Ice Age.

You can see all this for yourself; go out and climb Overlook.

   Reach the authors at randjtitus@prodigy.net. Join their facebook page thecatskillsgeologist.com.

Woodstock in the Ice Age; South by Southwest

On The Rocks; The Woodstock Times. 2008

Updated by Robert and Johanna Titus

We and many of our colleagues practice an art that doesn’t have a formal name. It should go by the name “rockcraft,” but to our knowledge that word is never used. Rockcraft must be related to woodcraft, both are outdoorsy pursuits. A person who practices woodcraft is familiar with camping out, especially in the wilderness. They know the plants and the animals and know how to read the signs and the seasons. They are well-versed in outdoors survival skills, mostly through experience.

People who know their rockcraft, are similarly experienced. After years of outdoors study, they know how to read the signs of the rocks. They are alert to what the rocks have to tell them. Rockcraft is a less known skill; there are no b\ Boy Scout merit badges in rockcraft. Also, rockcraft is not likely to help you survive if you are lost in the wilderness. But it is a very rewarding skill, simply for the understanding of what nature has to tell you about its distant past. In a way rockcraft is what this column is all about.

One of our personal favorite aspects of rockcraft is the pursuit of glaciers. Of course, there are no glaciers in this area and there have been none for about 14,000 years, but there once were and they can still be followed. The main thing to watch for in pursuing a glacier is the glacial striation. Advancing glaciers are likely to bulldoze away all or most of the soils that they overrun. having stripped the landscape down to bare rock, the ice scrapes across it. If, as is highly likely, the ice is carrying cobbles and boulders with it, then those rocks will gouge scratches into the bedrock as they are dragged along. This is the origin of glacial striations, among the most commonly seen ice age features.

If you know where to look, striations can be quite commonplace. Naturally any time you see bare bedrock, it is worth taking a look. We always watch for roadside outcrops. It is commonly the case that after the highway construction has cut into the bank, erosion will sweep the rocks clean and expose the striations. We also watch the tops of ledges; they are so common throughout the region and often reward us with striations. Then there are the tops of cliffs along the Catskill Front. We have found them at the top of Overlook Mountain and all along the escarpment trail.

Naturally, the striations will be aligned according to the direction of movement of the ice. So, when we find them, we can take a compass reading and when we have collected enough such readings in an area, we will be able to document the history of the flow of ice.

During the ice age, glaciers expanded out of northern Canada and drove their way into the northern United States, including the Hudson Valley. We can trace the path of that ice as it passed through this area. What you do is go out and watch for those glacial striations. We have been doing this for quite some time now and we think that we have collected enough data to form a firm opinion of which way the ice flowed.

And we found absolutely no surprises. The ice, here in the Hudson Valley, was funneled through the valley. The striations almost always line up close to a compass direction of south 30 degrees west. It’s sort of a chicken and egg issue here. The structure of the bedrock geology first dictated the alignment of the valley and steered the glaciers. But then, the glaciers scraped and eroded the valley as they passed through it. In so doing they enhanced the southwest lineation of the valley by straightening and steepening the great wall of the Catskill Front.

Even if there were no surprises in what we found, it was still nice to have good documentation of the flow of the ice and to further demonstrate the relationship between the Wall of Manitou and the glaciers that once flowed past it.

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

The Zena Ice Field

On the Rocks; The Woodstock Times, 2009

Updated by Robert and Johanna Titus

The very first time we ever visited Woodstock, we entered by way of Zena Road. We slowed down at the wonderful view of Overlook Mountain. We remember a cornfield there and that added to the view. Some time later this field was threatened with development. Thankfully, the Woodstock Land Conservancy managed to save it and now the land and its grand view are, forever, just as they were and “have always been.” The site with its view is a very emblem of Woodstock itself. We can all be very glad it has been preserved.

But we are geologists, and we see a lot more when we pull over there and gaze north. We did so recently, and it was quite the experience. We saw the Zena field as it was 23,000 years ago. It was heavily forested then, and we could only see the top of Overlook. The forest was just what you would expect; there were oaks, maples and birch. There were a lot of chestnuts back then too. Many of these were enormous trees, there had never been any cutting in this forest; trees grew to great age and size.

As geologists we were blessed with being able to watch this forest for centuries, a lot of them. We noticed that the summers were getting shorter and grayer. They seemed to stop getting really hot; in fact, it was downright cool and cloudy. There seemed to be fewer warm weather birds. We thought there were fewer summer insects as well; we rarely heard katydids.

The winters were not all that cold though, but they too were overcast. It always seemed to be about 31 degrees out and snowing. We got to be a little weary of the snowfall, but it would not stop. As more centuries elapsed, we noticed that the trees atop Overlook seemed to sicken. Even in late August they seemed pale, even yellow. With more centuries I saw that some of them were dead.

Then down below, we noticed the same affliction in the forest of Zena. Their August leaves were small and yellow. Summer was just not warm enough to allow healthy growth of these trees. What was going on? We were the only humans in all of North America; there was nobody to go and ask.

Now we noticed that the snowfall was lasting into May and then June. The new snows were returning in October and even late September. We are used to climatic cycles, but our droughts are always followed by rainy seasons, our heat waves are balanced by cold spells. We were watching a one-way process. Woodstock was changing into a land without summer. Now the forests up on Overlook were all dead and the trees of Zena were dying as well.

There was something else. we saw weeks of weather when the skies were blue, clear, and cloudless while cold, very dry winds blew steadily out of the northeast. We wondered if there was something cold and dry in that direction. It was a relentless wind that got on our nerves after a while, but it would not stop.

The snows lay on the ground longer into the “summer” season. We saw dirty old snowdrifts in mid July. One summer the ground never thawed out and that was the year all the trees finally died.

Trees don’t make noise, but once they are dead all the noise makers soon leave. We watched as all the birds, all the noise-making insects and all the grunting animals left. The dead forest became unnervingly silent.

But real silence was rare; those howling dry winds soon desiccated the dead trees. Soon, the brittle twigs were blown down, then the branches and finally even the dry limbs crashed to the ground. The forest was a very noisy place . . . until only the tree trunks were left.

Later we heard a distant crashing and falling sound of a different sort, and then another. Soon this became routine, and we wondered what was going on. It took months, but then we found out. A great glacier was moving south, through the Hudson Valley and it was plowing down all the dead trees. Now, at last, we comprehended. When the glacier got to us, we climbed up upon it and reached its top. Now we had a better view of it all. As far as we could see to the north and east there was a flat, endless expanse of ice. It was a frightening sight. To the west and south, dead forests somberly awaited their destruction.

Then we looked up and beheld a horizon of ice rising above the top of Overlook itself. Soon, this great sheet of ice, thousands of feet thick, stretched from the western to the eastern skyline. Down below, the local ice mostly advanced westward; Woodstock was next.

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