Thomas Cole at Kaaterskill Clove

The Catskill Geologists; The Mountains Eagle

Robert and Johanna Titus; Jan. 18, 2019

We have long admired and appreciated those nineteenth century artists of the Hudson River School of Art. Geologists typically do; the art of landscape should, we would think, appeal to those scientists who, after all, study landscapes. So, it should not be surprising that, when we look at one of those paintings, we look into them and see, not just the fine art, but the geology that is there.

We are betting that you have been to Kaaterskill Clove. If so, then you will recognize it on the painting that Thomas Cole did there in 1827. See our illustration. Cole is widely remembered as the founder of the Hudson River School. Suppose a geologist from some other continent came along and looked over this painting. What would they see? What would they conclude about this landscape?

The Clove – Thomas Cole, 1827. Courtesy of Wikimedia Commons.

   We suspect that the first thing that they would notice is the steepness of this landscape. There is a canyon here and its slopes are very, very precipitous. A geologist would conclude that the stream that cut this canyon was a very active one. Geologists used to call this sort of thing a “youthful” stream. The hypothesis was that this landscape had most likely been recently uplifted, perhaps by powerful tectonic events. The stream had responded by aggressively cutting into the landscape. Rapid downcutting had produced those steep walls. Hence, our hypothetical geologist would be imagining a tectonically active landscape – at least at first.

Our geologist would look at the bedrock in the foreground. He, or she, would conclude that it was pretty resistant stuff, probably a sandstone. They would go on to conclude that this sandstone made up the capstone of a waterfall. You can’t see the waterfall in this picture but the steep slopes, beyond, indicate the falls that do exist there.

But then, our geologist would look into the distance and see what we know is the broad floodplain of the Hudson Valley. That would be a problem. Such floodplains take a lot of time to form. That is why they were, some time ago, called “mature streams.” They were emblems of very old landscapes.

So now our geologist would have a true dilemma. How could an old age landscape be associated with a youthful one. Well, here is where the two of us have to come in and answer some tough questions. We are locals and we know our way around here. Our mature Hudson valley floor is indeed an old landscape. The Hudson valley is tens of millions of years old and so it has had time enough to have earned its maturity. So how did its youthful landscape develop? How did the steep slopes of the Hudson Valley form so that Kaaterskill Creek could plummet down it’s slopes? That’s something that our foreign geologists could not figure out.

But we do know this secret and it takes us back to the Ice Age. Back then, our mature Hudson Valley was filled with ice. An enormous glacier was advancing to the south. It ground up against the wall of the Catskill Front and steepened it. That helped make that youthful landscape. If you have been to the Catskill Front, then you know about this.

Take another look at the Cole painting. Fill the Hudson Valley with ice; that ice has stopped advancing; it is now a melting glacier. Now fill that nearby canyon with raging, foaming, pounding, thundering, meltwater torrents. We are guessing that Cole would have enjoyed painting that scene.

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

Thomas Cole at Kaaterskill Clove

The Catskill Geologists; The Mountains Eagle

Robert and Johanna Titus; Jan. 18, 2019

We have long admired and appreciated those nineteenth century artists of the Hudson River School of Art. Geologists typically do; the art of landscape should, we would think, appeal to those scientists who, after all, study landscapes. So, it should not be surprising that, when we look at one of those paintings, we look into them and see, not just the fine art, but the geology that is there.

We are betting that you have been to Kaaterskill Clove. If so, then you will recognize it on the painting that Thomas Cole did there in 1827. See our illustration. Cole is widely remembered as the founder of the Hudson River School. Suppose a geologist from some other continent came along and looked over this painting. What would they see? What would they conclude about this landscape?

The Clove – Thomas Cole, 1827. Courtesy of Wikimedia Commons.

   We suspect that the first thing that they would notice is the steepness of this landscape. There is a canyon here and its slopes are very, very precipitous. A geologist would conclude that the stream that cut this canyon was a very active one. Geologists used to call this sort of thing a “youthful” stream. The hypothesis was that this landscape had most likely been recently uplifted, perhaps by powerful tectonic events. The stream had responded by aggressively cutting into the landscape. Rapid downcutting had produced those steep walls. Hence, our hypothetical geologist would be imagining a tectonically active landscape – at least at first.

Our geologist would look at the bedrock in the foreground. He, or she, would conclude that it was pretty resistant stuff, probably a sandstone. They would go on to conclude that this sandstone made up the capstone of a waterfall. You can’t see the waterfall in this picture but the steep slopes, beyond, indicate the falls that do exist there.

But then, our geologist would look into the distance and see what we know is the broad floodplain of the Hudson Valley. That would be a problem. Such floodplains take a lot of time to form. That is why they were, some time ago, called “mature streams.” They were emblems of very old landscapes.

So now our geologist would have a true dilemma. How could an old age landscape be associated with a youthful one. Well, here is where the two of us have to come in and answer some tough questions. We are locals and we know our way around here. Our mature Hudson valley floor is indeed an old landscape. The Hudson valley is tens of millions of years old and so it has had time enough to have earned its maturity. So how did its youthful landscape develop? How did the steep slopes of the Hudson Valley form so that Kaaterskill Creek could plummet down it’s slopes? That’s something that our foreign geologists could not figure out.

But we do know this secret and it takes us back to the Ice Age. Back then, our mature Hudson Valley was filled with ice. An enormous glacier was advancing to the south. It ground up against the wall of the Catskill Front and steepened it. That helped make that youthful landscape. If you have been to the Catskill Front, then you know about this.

Take another look at the Cole painting. Fill the Hudson Valley with ice; that ice has stopped advancing; it is now a melting glacier. Now fill that nearby canyon with raging, foaming, pounding, thundering, meltwater torrents. We are guessing that Cole would have enjoyed painting that scene.

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

More About Bluestone

The Catskill Geologists; The Mountain Eagle 3-15-26

Robert and Johanna Titus

Recognition, they say, is the first step towards learning–and liking something. Can you walk down the beach and put names on all the shells you see? Well, then your interest in mollusks will surely blossom into a love. It’s the same for trees, flowers and birds as you walk through the woods. And it’s very much the same with our science of geology. As you learn to identify fossils, minerals and rock types, you just naturally develop an affection for them. Soon you join a rock and mineral club and then it all gets better.

We play upon this in our columns; the more you learn to recognize geological features, the more fascination you will likely develop for them. Our job is only to introduce you to these features; you do the rest. In recent columns we have been walking down bluestone sidewalks and learning to recognize features upon them. They are widely seen throughout the Catskills and the two of us have become rather fond of them. We have walked down so many of them and learned to recognize the secrets that they can reveal to the trained geologist’s eye. Today, let’s introduce you to yet another.

Take a look at our photo; it shows a bluestone sidewalk slab displaying features called current lineations. They are also commonly known as parting lineations. We have also heard them called flow lineations. Whatever the name, these are very low ridges of sandstone, lying on the surfaces of bluestone slabs. They are composed of very thin horizons of sand, with the ridges often rising just a few grains above adjacent lower horizons.  Once you train your eyes to see these, you will find them to be common and easily spotted. But—what on earth are they?

Notice how strikingly parallel they are. They all pass left to right in our photo. That is a big clue. These are the products of river currents that long ago passed across the floor of, we guess, an ancient stream bottom. Geologists have calculated that these were strong currents, traveling at two to four feet per second. Some geologists claim they can tell which way the current had been going. In our photo that might have been left-to-right or right-to-left. But we have never been able to convince ourselves that we can do that. Ours, here in the Catskills, formed on the bottoms of the Devonian age streams that flowed across the ancient Catskill Delta. That delta was a heap of sediment that formed at the bottom and west of the Acadian Mountains that once towered above today’s northern New England. The Catskill Delta hardened into what are called the Catskill Mountains. And, with that petrifaction witnessed many stream deposits turned into rock.

At the time of deposition these sedimentary structures would have been nearly invisible. It was only when the bluestone slabs were split by quarrymen that they sprang to life, becoming something the eye could take notice of. The process of splitting brought the lineations to light—quite literally.

So, now you have learned something you likely didn’t know before. Now, your walks down our bluestone sidewalks will take you into the Devonian and onto the floors of those ancient streams. Perhaps you should bring your children along—or, like us, bring your grandchildren.

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

A fossil soil?

The Catskill Geologists; The Mountain Eagle; May 11, 2028

Robert and Johanna Titus

The intersection of Rtes. 23 and 32 is one of those locations that we just happen to pass all the time. We drive west on 23 and then turn right onto 32. There is an outcrop on 23, just east of that crossroads. The strata there record the deposits of the outer edge of the old Catskill Delta. We are transported through time back about 385 million years, and find ourselves surrounded by a low, almost flat landscape, covered with a scrubby foliage of very primitive plants. Off, a short distance to the west, is the shore of something called the Catskill Sea. We can’t see those waters but we know they are there. We can smell the saltwater.

We stand on the shore of a sizable river which has flowed across the delta and is headed toward that sea. Its currents flow by us, right to left. The channel bottom is blanketed in soft light-colored sand. All around us is that foliage; it consists of relatively short tree-like plants; we would have to call them shrubs. They reach up to chest level. They are very exotic looking plants; none of them are alive today. To our eyes, they seem very primitive; we can’t guess why at first, but soon we notice that they do not have proper looking leaves, nor any flowers. Their bark is covered with a closely spaced ornamentation of diamond shaped scars. Nothing like them can be seen in the Catskills today.

We look down and see that the soil, beneath us, has the shade of a dull brick red. It is warm on this ancient day in this distant past, and that red soil tells us that this is the norm for these times. Not only have we traveled into the distant past but the climate here is tropical. The soil is a tropical one.

And, POOF, our journey into the past is over and we have traveled, in an instant, back to the present. We are again standing along the side of Rte. 23 – and we haven’t moved an inch. We look at that outcropping once again and see, for the first time, just exactly what is in front of us. There is a horizon of red strata. It is cut by vertical structures.

We are looking at a fossil soil. Above it, lies the gray sandstone strata of an old river channel, those other gray sandstones, below, are from another such river channel. But, it is that reddish horizon that captivates us. They document something that we are familiar with. Those vertical structures are shrinkage cracks. They form within soils that are subjects to alternately wet and dry seasonality. During wet seasons of the year, they soak up water and expand. But, during dry seasons, they desiccate and shrink. That’s when the cracks form.

Today, such soils are called vertisols, named after their vertical cracks. Now, we look at this soil profile again, and realize that we have been there. Just a short time ago we had traveled back in time and stood on the shore of one of those two rivers. And we had stood upon that very soil. We reach out and touch the top of that red soil horizon. And then we lean forward and look closely; we are searching for our own footprints. But we can’t find them; time travelers do not leave footprints in the past.

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

The vastness of time – Part 1: The Catskill Limestones

The Catskill Geologists; The Mountain Eagle; Feb. 12, 2020

Robert and Johanna Titus

To be a geologist is to live on a tiny island in a vast sea of time. Earth history extends backwards a full 4 1/2 billion years. The future of our planet will be equally long. Our three score and ten is so small compared to all that. But a fair question is: how do we know that? The best answers are provided by geochemists who can make these determinations from the study of various chemical isotopes found within some rocks. That’s hard science but it does not make for a very good read. We would like to take a different approach to this question and, at the same time, a far more spiritual one.

Have you ever been to Thacher Park? It lies at the edge of the Helderberg Escarpment and overlooks a distant Albany. It’s a picturesque location, a massive cliff rising above the Hudson Valley. The Helderberg Escarpment is composed of the Devonian aged Helderberg Limestone, rocks almost 420 million years old. It’s a very important unit of rock. It’s hundreds of feet thick and extends westward far past Syracuse. It makes up a great ledge that runs down the Hudson Valley as well. In fact, it’s our recollection that this limestone is spread out across most of eastern North America. That’s a big unit of rock. What’s the story behind this story?

Thacher Park

Well limestones, in fact, conjure up quite a tale. Each of them formed in a shallow tropical sea which had been floored with limey sediments. But what exactly is limestone? Take a look at our second photo; it shows a view of a microscopically thin sheet of a typical fossiliferous limestone. The dark particles are fossils, fragments of ancient shellfish skeletons. Those had been mostly shells that came to be broken up and rounded in active seafloor currents. They are composed of the mineral calcite, CaCO₃, the very stuff of limestone. The clear white material in between those fossils is pure crystalline calcite cement.

This is a typical limestone lithology and it speaks of great lengths of time. How long did it take for all those generations of shellfish to live and die? How long did it take for chemistry to produce all that cement? The answers to both questions speak of enormous lengths of time. It gets worse. As we have seen, that Helderberg Sea was huge, being spread out across so much of north America. How long did that take to form? Again, the answer to the question forces us to contemplate what seems to be endless eons.

The spiritual part comes along when we let ourselves waft back through time to visit Thacher Park during that early Devonian time period. Suddenly we find ourselves drifting across the shallow Helderberg Sea. Below us we see reef building animals called stromatoporoids, animals now long extinct. We rise up a bit into the air. We are the mind’s eyes and we can do that. Below us we now see the dark shadows of those reefs. All around them are the pink limy sands that will someday be limestones. They are dotted with living shellfish. Here and there we see green patches of algae, plant like creatures that flourished in those sunlit waters. We rise up still higher and higher. Now we are thousands of feet up; soon it will be miles, many of them. The full expanse of the Catskill Sea is opening up before us. It is an aqua colored sea spread out across the vastness of a now global geography. It looks like something that has always been there; it looks like something that will always be there. Looks are deceiving.

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

A real geological mystery, and at Pratt’s Rock

The Catskill Geologists; The Mountain Eagle 5-31-19

Robert and Johanna Titus

We were invited to speak at the Pratt Museum recently. Our topic was the glacial geology of the Schoharie Creek Valley. After that, a group of us went to Pratt Rock and climbed up the trail there. We took a look at Colonel Pratt’s carvings and continued on to see some nice ice age features. But, along the way, we ran across one of those mysteries we have long struggled with.

We were first alerted to this particular mystery by Paul Misko, a veteran Catskills hiker. Paul told us of some “very strange structures he had found in Phoenicia. Paul has a real eye for unusual geology, so we paid attention to his “very strange” claim. We saw his Phoenician structures and now we have found more of them at Pratt’s Rock. Take a look at our photo and then climb up the steep incline at Pratts Rock and keep an eye out. Towards the top you will find sizable ledges of sandstone. This is rather commonplace stuff: very typical Catskills bluestone ledges. These ledges are, in essence, the cross sections of some very old streams. It’s, like all rocks in the Catskills, Devonian in age, something a bit less than 400 million years old.

None of this surprised us in the least but that’s where we encountered that mystery. Take another look at our photo and see what you think. See the cluster of closely spaced and very strange cavities just above the hand. Their shapes vary considerably, but they all show a sort of boxy nature, and they seem to form an interlocking network. We would like to use the term honeycomb here, but honeycombs show a consistent hexagonal shape; we don’t see that with these. The rock remaining in between these cavities is narrow. The cavities do not penetrate too far into the rock, just a few inches. And there is no reason to think that there is another horizon of these cavities under the ones that are visible. Thus, they appear to be surficial features. Many of these cavities are spaced so close together that they comprise a bigger compound cavity. Whatever it was that formed them was focused.

All in all, this is one of the most puzzling phenomena that we have seen in the Catskills. There is no trouble putting a name on what is here; these structures are called “tafoni.” Each individual cavity is a tafone; lots of them are tafoni. And the terminology keeps getting better; when tafoni occur on cliff faces, as here, then it is called lateral or sidewall tafoni. But putting a name on something is not the same as understanding it.

What are these features? They seem to be chemical weathering phenomena. Somehow, they appeared on the rock surface and grew slowly into their observed shapes, but exactly how? And, also, how is it that they grow in size until they abut each other but do not grow into each other? How do they grow in size without intersecting? Those are very puzzling questions and just naming these things does not provide answers.

Tafoni have been weakly associated with poorly defined stratification on the sides of cliffs and that is the case here: sort of. But that still leaves a lot unsaid. Why does this “association” occur? What are the specifics? Salt is commonly cited as an agent in tafoni development. They are sometimes found on coastal outcroppings, splashed by ocean waves. But there is certainly no source of salt here on a sandstone cliff in Prattsville, and certainly no waves. And, why do only a few Catskill Cliffs display these? That begs the question: what exactly is different about his cliff? Why don’t all cliffs have tafoni? Why isn’t it that none of them do? There must be something here, right in front of our eyes, which we have missed. This is the sort of thing that makes science so much fun.

Do you have any ideas or questions? Have you seen tafoni somewhere? Contact the authors at randjtitus@prodigy.net. Join their Facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”

The weathering of an old cliff

The Catskill Geologists

Robert and Johanna Titus

In recent columns we have been describing the many processes of the weathering and erosion of rock and would like to continue that today. Our goals, as almost always, are to train your eyes so you can take note of geological features that are all around you everywhere you go. Take a look at our photo. It was sent to us by a reader who calls himself “Mountain Mike.” He took the shot at the bottom of Kaaterskill Clove. Our reader was curious about those loose boulders lying at the bottom of the cliff on the lower right. How, he wondered, had they come about getting where they are? The answer to that question takes us back to the processes of weathering.

We rather suppose that if we could go there and find those boulders (and if we were a lot stronger than we actually are!) then we could lift them up and fit them back into the sandstone ledge that rises above them. In short, we think that they broke loose and tumbled down to where they are and those were probably recent events. That involves the physical breaking up of bedrock. How, exactly, did that happen?

There are two broad categories of weathering. The first and most important is called chemical weathering. We have been describing some of those in recent columns. They are chemical processes that break rocks down chemically and weather them away. The other big category is physical weathering. Physical processes break up rocks into fragments and crumble them away. Physical processes get us back to Mountain Mike’s rocks in Kaaterskill Clove.

We think that what happened here is called freeze-thaw activity. That all begins with the simple fracturing of bedrock. In Kaaterskill Clove that’s easy. The bedrock of steep cliffs is always leaning toward the bottom of the clove. Stresses result, cracks form and these initiate further physical weathering. It is inevitable that at least some rainwater will seep into the fractures. And it is also inevitable that, come winter, that water will freeze. That’s the important part. You see as water freezes it also expands and that is always by exactly 9%. A cubic centimeter of water will turn into exactly 1.09 cubic centimeters of ice. There is some debate here but the long and the short of it is that expanding ice will do two things to those original fractures. They will become wider and they will become longer. In short freeze thaw is a process that breaks up rock.

To make it all the worse the process is a cyclical one. Freeze thaw processes are likely to occur in daily cycles, especially in late winter and early spring. That’s when the daytime sun is quite likely to warm up bedrock to well above freezing. But the following night’s cold will take the same watery rocks and refreeze them. During nights waters will freeze, expand and induce the fracturing of the rock. The next warm day will see the ice melt; more water will seep into the fractures and set it up for further disintegration. It’s a virtually endless process. And it’s an effective one, especially at this time of the year.

Here’s the “trained eyes” part: Watch, in coming weeks, for the “appearances” of rocks and boulders at the bases of outcrops along the sides of roads.

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

Eroding an Old Pebble

The Catskill Geologists; The Mountain Eagle; Jan. 17, 2020

Robert and Johanna Titus

We have been talking about the various processes of the weathering of rocks in several recent columns. Let’s take a break this week and talk about weathering’s sister process: erosion. And, while we are at it, let’s pick one of the very strangest categories of erosion that you could ever imagine. But, first let’s define the process itself. Most types of erosion involve the lifting up of earth and the movement of it downhill and then into a nearby stream. It’s carried in the stream currents toward the nearest sea. Soils and sediments can frequently be eroded by streams and swept off down to the ocean. Do you live near the Susquehanna or Delaware rivers? Then you can look and see cloudy waters flowing past. That cloudiness is recently eroded earth that had lined the riverbanks and been swept up by the passing waters, probably during a recent storm.

River water is an active agent of erosion, but our topic today is focused on glaciers. “Streams” of ice can sweep up sediments and carry them off just like streams of water. In fact, glaciers are a lot better at that than rivers. Let’s look at our photo. It was taken on the sandstone ledge lying at the very top of Kaaterskill Falls. We were there during a dry spell in August a few years ago. We found this one along with three or four other similar pebbles. They quickly caught our eyes.

118 – Eroded pebbles 1-17-20

What you see is a quartz pebble that had been deposited in a Devonian age river sand about 385 million years ago. Those river sands eventually came to be hardened into the sandstone that makes up the ledge atop the falls. But, notice that the pebble has been shaved off right to the level of that ledge. How could that be? Shouldn’t that tough quartz pebble rise up above the softer sandstone? Why doesn’t it?

Well, when we spotted this pebble, we immediately recognized what had been going on here. We knew that a glacier had, during the late Ice Age, risen up Kaaterskill Clove and passed across this ledge. Sand, concentrated at the bottom of the passing ice, had cut right through the pebble, planing it off and slicing it in half. That left behind this most remarkable image of a most remarkable type of erosion.

Our columns always aim to give you a trained eye. We discourage you from walking about on the top of Kaaterskill Falls. But we hope that, come next summer, you will walk along the Blue Trail on edge of the Catskill Front, the Wall of Manitou. Back during the Ice Age, glaciers rose up out of the Hudson Valley and swept across the sandstones there. Many of these sandstones also had quartz pebbles buried within them, and many of those came to be planed off by the ice. These are especially common just south of the well-known Boulder Rock, which is south of the Catskill Mountain House hotel site. They are also common on the yellow trail, north of the old hotel. We commonly take people to these two locations and show them these planed off pebbles. It makes a real impression on them and we enjoy seeing their reactions. You can visit and experience your own reactions. We will come back to this peculiar form of erosion next week in our next column.

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

The weathering of another very old rock

The Catskill Geologists

Robert and Johanna Titus

This week let’s look at another picture done by our friend, photographer Art Murphy. This is a gem! We like Art’s photographs so much that, a few years ago, when we had the chance, we did an exhibit with him at the Catskill Center in Arkville. We displayed a number of our most interesting Catskills rock specimens, and, across the room, Art put up a number of his photos. Each exhibit, rock or photo, displayed something from the Devonian history of our Catskills. The two exhibits complemented each other, and we think the show was a success.

But that was then, let’s get down to this week’s business. We have been talking about chemical rock weathering in recent columns. Those are processes whereby chemical activities work to destroy a rock, to break it down, and in a sense decompose it. They eventually turn it into soil. Weathering is one of those fundamental processes in nature. It takes rock, turns it into earth and sets it up to be eroded. As they erode, their landscapes comes to be destroyed. Given enough time all the rocks of a mountain range will weather and erode. Even great mountains, no matter how tall they might have once been, will simply erode away.

Last week we saw oxygen “rusting” the iron bearing minerals in rocks. This week we will see something similar. Take a look at Art’s photo. See the prominent yellow and brown stripes on the surface. The blue gray is the natural rock beneath those hues. It’s a handsome rock and that is why Art chose it to be photographed. It looks as if an artist, armed with a brush, had painted that rock. It’s not abstract expressionism; it’s a form of art that nature does herself. Mineralogy is not our field, so we are going to have to do a little guessing here, but we think we know what was going on when all this formed. We believe that the yellow is the same stuff we saw last time; we think it’s the mineral limonite. It formed when the oxygen in water attacked the iron that was already in the rock. So then, what is the brown? We are guessing once again; we think that it is a related iron oxide, a brown one, and that is probably a mineral called goethite. It’s just a little differently oxidized than limonite. So, how exactly might these minerals have formed? We think that there had been a crack in the rock and that water soaked into it. The oxygen in that water attacked the iron in the rock and turned it into limonite or goethite, depending on how much oxygen was available. There was just a little extra oxygen near the edge of that water. There the limonite was produced.

After a period of time, the water evaporated, and those minerals crystalized, left behind as the film we see on the surface of the rock. This was an initial step in the weathering of the rock. We are guessing all of this, but we like the story; it’s probably not all that far off. What’s most important is that we alert your eyes to watch for this sort of thing when you are out looking at rocks. We have more to write about weathering. Next week we will take it one step further along.

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

A scenic landscape

The Catskill Geologists; The Mountain Eagle; Dec. 13, 2019

Robert and Johanna Titus

Some landscapes are more picturesque than others. Our Catskills are truly blessed when it comes to scenery. For the two of us, however, it can be the geological past that makes a landscape even more remarkable than you might at first think. You travel south on Rte. 145 from Middleburgh and enter Durham. Watch for Stone Bridge Road on the left and turn onto it. You pass an ancient graveyard with fine old stone tombstones and beyond that is a very nice rolling farmland. Do you enjoy walking through such a cemetery, looking at finely made tombstones? Well. this a place for you. But, for us, it was that farm field that caught our eyes. What’s there? Well, take a good look at our first photo.

114 – Stone Bridge Rd. 12-13-19

We call this a rolling landscape and that is certainly true. There are so many sinuous curves here; the field gently rolls up and down sort of like the waters of an old Chinese print of a great stormy sea. There is hardly a geologist anywhere who would not look at this without seeing into its ice age past. We would like you to develop this sort of skill, so, we have a little explaining to do. Those sinuous ups and downs have names. The ups are called kames the downs are called kettles. They formed very late in the Ice Age. At that time this landscape was still thawing out. Many locations had large masses of ice buried in the earth here. How large? Well, many were the size of houses. That’ was a lot of ice in each of these. Most are thought to have been buried in earth. That earth acted as insulation and so each mass of ice took a long period of time to thaw out. Some suggest that the melting took centuries. As the thawing continued, a lot of that overlying earth collapsed upon the melting ice. That resulted in those sinuous kettles. The earth in between was left behind as those sinuous kames. There was more; we drove a short distance down Stone Bridge Road and there was a fine small shallow pool of water. See our second photo. That water fills a particularly deep kettle; it is called a kettle pond.

We are experienced geologists and it took but seconds for us to recognize the big picture here. We saw that we were looking at what is called a glacial moraine. That is a heap of earth that was bulldozed into place by an advancing glacier. That glacier advanced as far as it would– so long as the climate was cooling – bulldozing morainal sediments all along its front. Masses of ice came to be incorporated into these earths. Then the climate warmed up and the ice began its retreat. This new landscape began its thawing out. Those blocks of ice took the longest, but they did melt and that produced those kettles. As the kettles formed so too did the kames.

We stood along the road and looked down the valley and then returned to that ice age past. We viewed a still largely frozen landscape. We saw all those kames and kettles. A few of the kettles still had large masses of dirty ice rising out of them. We craned our necks and looked all the way down the valley as far as we could see. There, in the far distance, we saw a great glacier. It rose high above the valley floor and stretched across the entire valley width. Its front was badly fractured and enormous volumes of meltwater were pouring out of each fracture. This was truly a scenic landscape, perhaps more so to us than to others.

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