Robert Titus - page 11

Woodstock Park

ON THE ROCKS/ – The Woodstock Times – July 3, 1997

Updated by Robert and Johanna Titus

We went and saw the Jurassic Park movie recently. We happen to be geologists who specialize in paleontology so we thought that it was about time we saw the kind of life that we should be leading. The movie was a lot of fun and there was plenty of action and adventure. There were good-guy paleontologists and bad-guy paleontologists which is an angle we had never reflected upon before. We have enjoyed our own careers in fossils very much so far, but it is clear, from this vicarious experience, that we have missed out on a lot of excitement. Chasing Devonian brachiopods is just not the same as being chased by a Jurassic Tyrannosaurus.

If you see the movie, you may wonder what it was like here in Woodstock back during the Jurassic. The answer is that we don’t know. There are no Jurassic age rocks in this area. No rocks/no history is the way it works in Geology. Nevertheless, it is fair to speculate as to what it was like around here way back then. And, in fact, there are some Jurassic age rocks not all that far away. They can tell us a lot.

It was the Jurassic and the earlier Triassic times that witnessed the origins and early history of the dinosaurs. In New York State there are late Triassic and early Jurassic sedimentary rocks in Orange and Rockland counties; there are more in central Connecticut. Only a few fossil dinosaur skeletons have been found in these sequences, but the strata are just crawling with footprints. And there is an especially interesting species of dinosaur whose footprints are quite common in these rocks, a dinosaur that almost certainly once lived here in Woodstock. Its Latin name is Coelophysis, and it was a very fine specimen. It belonged to a group called the ostrich-like dinosaurs. Coelophysis wasn’t especially large, being only five feet tall and nine feet in length. It was, however, remarkably athletic. They were agile and lightweight, weighing in at a little more than 100 pounds. It’s probable that they were among the earliest predatory dinosaurs. Coelophysis had small forelimbs, but they were armed with long recurved claws. Its large mouth possessed numerous, knife-like teeth. All in all, the animal would have been quite effective at ripping its prey apart, making it an excellent movie dinosaur.

But that wasn’t the scariest thing about this dinosaur. There are sites in New Mexico where their skeletons are so abundant that paleontologists have speculated that they must have hunted in packs. That really gets us to the Jurassic Park stereotype of dinosaurs as vicious marauders. And there may be a great deal of truth to the stereotype. We once saw a series of dinosaur trackways. They were all the same species, all the same size, they were spread out evenly, and all heading in the same direction – a skirmish line of predatory dinosaurs! We had 15 students place their feet in the tracks and, on signal, they all stepped forward, laughing, growling and retracing those 190 million year old trails. Dinosaurs can be fun, at least the dead ones that can’t eat you are fun.

   Coelophysis probably did live here in Woodstock, and dinosaurs are part of our local geological heritage. It’s too bad we can’t go out and hunt their bones here. We don’t know if there ever were any Jurassic age strata in Woodstock, but if so, they would have eroded away millions of years ago. All evidence of local dinosaurs has been gone all that time. Want to see some real dinosaur fossils? Travel to Dinosaur State Park, near Rocky Hill in central Connecticut. There is an outdoor display of footprints there. Maybe one of the dinosaurs that left its footprint in Connecticut came from Woodstock.

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

Burroughing into Natural History

On the Rocks; The Woodstock Times May 15, 1997

Updated by Robert and Johanna Titus

Throughout our Hudson-Catskill landscapes there are many secluded hollows. All of them have a geological story, but some of them are far more important in other ways. Famed nature writer, John Burroughs, knew many of these Hudson hideaways and he chose one of the best for his own. He built himself a small cabin in one of those hidden hollows. It’s still there, called “Slabsides,” it’s a monument to Burroughs himself.

Burroughs didn’t need Slabsides for shelter, he just needed a small, personal retreat. He already had a fine family home, called “Riverby” nearby. Riverby was situated in West Park, on the banks of a far more bucolic Hudson than the one we know today. Burroughs even grew grapes on this small Hudson estate. But it wasn’t grapes that was the primary Burroughs family harvest; it was literature. John was one of 19th century America’s foremost writers. He was a man of letters, the literary critic who virtually discovered Walt Whitman. Burroughs also wrote of philosophy and religion. But it was as a natural history writer that he gained his greatest lasting fame, and as such he is still most fondly remembered.

Burroughs and several late 19th/early 20th century colleagues, made up a literary wing of the turn of the century conservation movement. But the old “Sage of Slabsides” was not an environmental activist. He was well-known to avoid all strife, political and otherwise. To two generations of readers, he was the benign figure of America’s grandfather. Not so, many of his close friends. Teddy Roosevelt was never known to have avoided trouble, he thrived on it. And the crusading John Muir’s views on the environment were decidedly activist. Nevertheless, both valued their friendship with John Burroughs and each greatly appreciated his soft, philosophical approach to nature. Both were visitors to Slabsides.

The hollow is a great one for the likes of us. Wherever we look, we can see the images of a particularly rich geologic past. First there are the fine bedrock exposures, sedimentary rocks from the depths of the Silurian sea that was once here. The strata belong to a unit of rock called the Quassaic Group. These well-cemented, brittle old sandstones formed way down at the bottom of that old Silurian age sea. That was more than 400 million years ago. Then there are the scars of glaciation that the jagged rocks reveal. We can easily imagine the flow of ice coming out of the northeast. As glaciers overwhelmed the old hollow, they hacked away at the bedrock and carved the ruggedness into the hollow. Finally, there are the moist, dark earths of the hollow’s floor. Burroughs grew asparagus here, but there is a much older story to the soils. They accumulated in a poorly drained swamp that formed here after the ice melted away. Who knows what form of fossil plants and animals may be buried in the fertile black muck that Burroughs prized so greatly.

But it’s hardly the geology that draws people here, it’s Burroughs old cabin and its legacy. Slabsides is in very good condition for an old house, but it’s not likely to ever be featured on “America’s Castles” or in Victorian Homes magazine. It’s not much, just a tiny handmade cabin. Its only real architectural distinctions are the rough bark covered planks that give the house its name. We preserve the great mansions of the Hudson Valley, and we should. But many people, a century ago, lived in very modest homes like this one, and very few of those are left. Slabsides is a reminder of the kinds of homes that existed before the invention of row houses or trailer parks.

Most of the time the hollow is quiet, but twice a year the John Burroughs Association meets for “Slabsides Day.” Lisa Breslof, secretary of the group, told us that their main goal was to keep the name of John Burroughs alive and to keep his literature in the public eye. More prosaic goals included maintaining Slabsides and the many Burroughs memorabilia.

We have been members for years now. In his later years, Burroughs was a pretty good geologist as well as naturalist. He wrote quite a bit on geological topics and hence our interest.

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

Escalator in Time

On the rocks/ The Woodstock Times; May 8, 1997

Updated by Robert and Johanna Titus

Last time we took an elevator into the earth and had a look at the geological history that’s buried in the strata of Overlook Mountain. It’s a great trip of the human imagination, a voyage of the mind’s eye. But it leaves a person wanting to see the real thing. In that column we left you stranded, about 8,000 feet below the peak of Overlook, on the shores of an ancient sea. This week let’s get on an escalator and ride back to the surface. Get your car, this trip won’t be imaginary.

Let’s start just west of Saugerties, at the intersection of Rte. 212 and Rte. 32. Drive north on Rte. 32. You won’t go far before you start noticing light gray rocks, mostly on the right side of the road; this is the Onondaga Limestone. It’s a good solid rock which makes up many fine outcrops. It’s not much to look at, but to a geologist it conjures up a most attractive image. The sediments that once made up the Onondaga were deposited on the floor of a shallow, tropical sea. If you wanted to see something like this today, you would have to travel to Florida or the Bahamas. First picture beautiful aqua-colored seas, soft pink beaches and a mild tropical climate, and then look about you in the Hudson Valley of today. Things change – in 400 million years.

Exactly two miles north from where we started, the road veers to the left and cuts through a major exposure of the Onondaga. Sizable cliffs can be seen on each side of the road. Stop here and take a good look. On the right side of the road, below the billboard at the far end of the outcrop, we found some fossil shellfish. We had to look carefully, but they were there. These were the invertebrates that lived in the Onondaga Sea.

Continue another half mile up Rt. 32 until you reach a fine outcrop just beyond the feed store. This is different, it’s a thick sequence of brown sandstones called the Mt. Marion Formation. Our escalator has taken us upwards through time; we are no longer on the floor of a pretty, shallow, tropical sea. We are now at the bottom of a deep ocean. The thick beds of sandstone record moments of rapid deposition of sand on the bottom of this sea. The sequence is so thick that one wonders where all of that sand could have come from. Also, the beds are steeply inclined. Why is that? Beds of sand should be deposited in horizontal sheets, not inclined ones.

The answer to both these questions is that these Hudson Valley strata record the history of a great geological event. Off to the east, in today’s New England, a mountain building event once occurred. There an ancient version of the Appalachians, called the Acadians, rose to great elevations. All mountains crumble and as these began to be eroded, enormous amounts of sand poured into New York State. Also, mountain building deformation produced the inclined strata that we see on Rte. 32. It’s brought these rocks to the surface, they’re the same strata we saw thousands of feet beneath Overlook!

Continue west on Rte. 32. As you reach Palenville the steep Catskill Front begins to loom above. Gaze upwards and you will be able to start really appreciating the full meaning of geologic time. Up there, all the rocks are clearly stratified. They are mostly sandstones, all from sands eroded off those old mountains. You are looking at the deposits of the great Catskill Delta, a complex of sediments accumulated at the base of the old Acadian Mountains. Once this was a mass of soft, wet sands, similar in size and scope to southern Louisiana where the Mississippi empties into the Gulf of Mexico.

Stop in Palenville, take your time, and really gaze at this sequence. Each horizon, up there, took its turn being the surface of the earth. Each was either the floor of a shallow sea or the surface of a delta landscape. Each of these landscapes and seascapes, in its time, seemed as permanent as any you see today. But both the Catskill Delta and the Acadian Mountains that produced it have been gone for hundreds of millions of years. They came to be buried in the relentless course of geological time. Continue your drive up into Kaaterskill Clove and pass hundreds of more feet of strata – and history; it really is an escalator ride through time.

Contact the authors at randjtitis@prodogy.net. Join their facebook page at The Catskill Geologist.

Elevator in Time

On the Rocks; The Woodstock Times

Updated by Robert and Johanna Titus

You’ve likely been to the top of Overlook Mountain and know the site of its fire tower. Imagine for a moment that there was an elevator shaft up there. This is a special one, a time elevator, built for geologists to take them back into Woodstock’s distant past. This elevator takes you down into the earth, through the many layers of rock which make up Overlook. You don’t stop at floors; you stop at moments in time. There are four doors, each facing one of the four compass directions. When the elevator stops at some ancient moment, the door opens upon the landscape as it then was. The only flaw is that this elevator can only take you to those moments of time that are recorded within the strata of Overlook.

We go in, push a button and down we go. The first leg of our trip is not very long and not very far. The east-facing door opens only a few feet beneath the surface. It’s 365 million years ago and out there is a mountain range; the Acadian Mountains rise above where the Taconics are today. They tower to ten or fifteen thousand feet above sea level. Their peaks are snow-capped. Below the white, the colors grade from dark blue to purple to red to rose. The slopes are dry, barren of plants, and shimmering in the heat of a high sun. In the foreground lies an enormous deposit of sand and gravel. The surface is scarred with rills and gullies, but there’s no water; it’s the dry season now. The elevator’s east door closes and the west one opens. That landscape slopes off to the west where there are a few dry stream channels and along the dry banks a primitive yellow green foliage struggles. The west door closes and down we go.

A short trip takes us another thousand feet, down to 373 million years ago. The east door opens, and we view an active river flowing toward us. It’s at high water but not flooding. The south door opens, and we see a dense jungle of very primitive plants. They are unlike anything seen today. The upper limbs have a “fur” of short, simple leaves. Below the limbs, the tree trunks are ornamented with the scars left when similar leaves fell to the ground. The weedy ground crawls with centipedes, spiders, and other bugs. At least these are familiar, but there are no animals or birds, and without them, it is as quiet as can be – unnervingly still. The door shuts: down we go, another 500 feet.

All four doors open, and we see a shallow sea floor, but no water floods in. It’s 378 million years ago. Around us heavily armored, sluggish fish-like creatures swim close to the bottom. Only the presence of primitive clumsy-looking fins confirms that these are indeed fish. This marine world begins to look a little more familiar when we see that the sea floor is littered with clams and snails, but the rest of the shellfish defy description; this is an alien sea bottom. The doors close.

After another trip we reach 407 million years ago at a depth of nearly 8,000 feet beneath the top of Overlook Mountain. We are more than a mile beneath the surface. Again, all four of our elevator doors open. We gaze out onto what, at first, looks like a meadow. But it’s really a very shallow sea floor. The sandy bottom is brightly sunlit, white, and dotted with the green of marine algae. Beautiful creatures rise above the algae. They are simple animals with the odd name of “sea lilies.” The name is appropriate, however; they have long stems and are rooted into the sand bottom. At the top of each of the long stems are five brightly colored, delicately branched arms. Gentle marine currents pass across this meadow. The arms grasp at the waters, vainly it seems, reaching for food. The doors all shut.

Shortly, when they open again, we look out upon a bleak, sunbaked coastal landscape. All around are broad tidal flats. They were flooded recently, but today they bake in the sun. All around are mats of dark, green-brown, leathery algae. They are rotting in the sun, and they stink. In between the algal mats are pools of saltwater brine. They have been drying out and are rimmed by deposits of salt. It is a quiet, desolate, and dead place, but this is an important landscape. This is the goal of our journey. These are the oldest sediments of the Catskill sequence and this landscape, bleak as it is, marks the very beginning of Catskill history, 408 million years ago.

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

Raindrops

On the Rocks/the Woodstock Times – March 20, 1997

Updated by Robert and Johanna Titus

We encounter many natural wonders in this field of geology and too often we take them for granted. There are so many things preserved in the rocks that really should not exist. Dinosaur footprints are good examples. How could something as ephemeral as a footprint in the mud be preserved 100 or 200 million years after they formed? The answer is that they really shouldn’t; it’s a one in a million chance. But what if there were ten million dinosaur footprints? Then ten of them would be preserved. If there had been a hundred million dinosaur footprints, then a hundred of them should still be around. One in a million shots become certainties if you just play the odds.

And geologists must learn to play the odds. Pretty much all of the fossils we find were originally one in a million shots. They were bones or shells or tree trunks that defied the odds, got buried, hardened into rocks, and were found. And then, when you have a million fossils, one of them is truly a grand discovery: a complete dinosaur skeleton, a mastodon frozen in the tundra, a little frog in amber and so on. Search for fossils long enough and you beat the odds.

We are used to this, but there are still things that we have a hard time believing, even if we see them myself. One of those odds-defying oddities can be found right here in the Catskills. They actually aren’t fossils, but the word fossil can be used to describe them. They are raindrop prints, often called “fossil” raindrop prints. Take a look at our photo. This surface just might display raindrop prints. At least that’s what they look like, maybe.

What could possibly be more ephemeral than a raindrop print? The drop falls out of the sky and leaves an impact crater in the soft earth. The crater is just that, a soft rim of earth thrown up by the impact. So far, so good, but how can something like this come to be preserved? Isn’t it likely that the very next drop will destroy the crater left by the last one? The answer is yes, of course, and the next 100 or 1,000 drops will also destroy any craters left about. And after the storm, won’t the earth be too soft to preserve an impact crater? Of course it will, the ground should be all mud, too soupy to preserve any such features.

And even if a raindrop print were to survive, wouldn’t wind eventually blow it away, wouldn’t animals’ step upon it, wouldn’t plants grow through it? Wouldn’t this and wouldn’t that! The answer is yes and yes, the raindrop should be destroyed.

And yet, there they are, . . . preserved in rock . . . little, bitty structures that look exactly like . . . raindrop prints! So, how did they get there? The prints are found on the surfaces of beds of red shales which are thought to have once been soil surfaces. That’s a helpful hypothesis and it adds some plausibility to the story. But shouldn’t the prints be lost in a mush of mud? To avoid that you have to imagine a very brief shower. A few drops sprinkle the landscape and then the “storm” is over, hardly before it had begun. But what about preservation? Next you have to let the soils dry out. This doesn’t turn it into rock, but dry soil is stiff enough to resist distortion. Next you want a flood to occur and submerge the flood plain. Floods are often not as catastrophic as the evening news coverage would suggest. Flood waters can often rise rather passively and bring blankets of new mud to bury the old soils. That can be done without much disruption of the rain drop prints. Continue this process for a very long time, bury the prints in a deepening thickness of sediment, and it will harden into rock. With that the raindrop prints are preserved. It’s a long shot, a very unlikely sequence of events, but it is possible, and it does happen. And that’s how it is that we can go and find such remarkably unlikely features in the rocks.

Such things are called primary structures. They are rather fun to watch for and they tell us so much about what the rocks represent. I would like to tell you where to go and find some raindrop prints, but that is hard to do. Look for red shales and these are common throughout the Catskills. Then pick through the shards of shale. If you are lucky, you may find some. If you are not lucky, well maybe next time.

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

What and where is a wind gap?

Windows Through Time; The Register Star

Updated by Robert and Johanna Titus

Sooner or later, every undergraduate geology major takes a course called geomorphology. It is the study of landforms and how they came into being. There are a lot of different landforms on the surface of our planet, and they go by a lot of names, a very large number of names. Do you know what a yardang is? Have you ever heard of a hoodoo? You should know what a drumlin is; we have written about them a number of times. And there are so many more names.

One of the most memorable terms and, at the same time, one of the most memorable landscape features is the “wind gap.” That is the subject of today’s column. What is a wind gap; where and how do they form? The term comes from the town of Wind Gap, Pennsylvania. That’s where the first wind gap was recognized, so that town got the honor of the naming of the feature. But we are not in the business of writing about Pennsylvanian geology; we want to describe a wind gap that is much closer to home.

The story of wind gaps picks up where we left off last week. If you remember that column, then you will recall that a geologist named Rudolf Ruedemann, back in the 1930s, postulated that Pennsylvania’s Lackawanna River once extended far to the northeast from where it is today. Today it is strictly a Pennsylvanian river. But Ruedemann conjectured that, about a hundred million years ago, the Lackawanna extended to the modern course of the East Branch of the Delaware and, from there, on to what is today the drainage basin of the Batavia Kill.

We recounted Ruedemann’s hypothesis, in that column, with some fondness. It is an old idea and it may be out of date, but we like it nonetheless. Well, if Ruedemann was right, then today’s Batavia Kill once flowed southwest as part of a once very much longer Lackawanna River. That is no longer the case. Today, the Batavia Kill indeed flows southwest, but only until it reaches the Schoharie Creek. It is a tributary of the Schoharie, and a small one at that. And it gets worse; in fact, we are not actually talking about the Batavia Kill. Our interest is in a smaller stream, a Batavia Kill tributary that branches off just a little east of Windham and follows Rte. 23 towards East Windham. Get out a good map and you can trace this creek; unfortunately it does not seem to even be large enough to merit its own name. But, even without a name, it may well have quite a heritage.

A hundred million years ago this little tributary might have been a part of Ruedemann’s very sizable Lackawanna River. But only if Ruedemann was right. We can test his hypothesis. If this little creek had once been a part of a larger river then it should have a valley much larger than is proportionate; let’s take a look. You can get an interesting view of this tributary if you take County Rte. 81 east from Rte. 145. At Dingman Road, and for the next mile or so, you can look up at the Catskill Mountain Front and see a cross section profile of the valley of this nameless creek. In fact, technically, it is not a valley at all; no water flows here; our nameless creek picks up a bit to the west; there is no stream right here!

Take a look at our photo. That profile seems big, disproportionately large. Even so, this feature is something that few would even notice. But we imagine that Rudolph Ruedemann did notice it and thought it was important. This is a classic wind gap. If Ruedemann was right then, long ago, the Lackawanna River flowed through this gap. Back then, the river continued back into New England. At that time this site would have been what is called a water gap. Wind gaps don’t have water in them; water gaps do. Ruedemann thought there had once been a powerful stream up there.

Make a visit to this location and look up. When we do, we find that we have traveled back in time to before there was a real Hudson Valley around here.  There is just a piddling unnamed creek now, but the old Lackawanna may have flowed by – up there – at that high level! Then its waters were diverted by the Schoharie Creek and, before that, by the Delaware River. Please take another look at last week’s column.  We can’t be sure if any of this is true, but it sure is interesting.

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

The Lackawanna River? Right here? 

Windows Through Time

Robert and Johanna Titus

Have you spent much time in northeastern Pennsylvania? If so, then perhaps you have seen the Lackawanna River. It’s not one of the world’s great waterways, but it does count for something. It begins in the most northeastern part of Pennsylvania and heads southwest until it reaches a confluence with the Susquehanna River.

Did you know that it flowed right through Windham? Yes, the Lackawanna River. Well, it doesn’t flow through Windham today, but it very well may have a hundred million years ago. If it sounds like we have a lot of explaining to do, well we sure do. Carl Sagan said it best when he said “extraordinary claims require extraordinary evidence.’ We are obliged to come up with a good story. Let’s give it a try.

For starters, let’s be sure to make it clear that the idea that the Lackawanna was a local stream is not ours. This notion was conjured up by one the many fine scholars that have worked at the New York State Museum these past two centuries. This one was named Rudolf Ruedemann. His career at the Museum occupied most of the first half of the 20^th century. He was, more than anything else, a paleontologist and he produced many fine works on New York State fossils. But that didn’t stop him from working on other branches of geology.

And that included river geomorphology, the study of river landscapes. Ruedemann must have had a way with spatial relationships, because when he looked at a map, he really looked at a map. Take a good look at today’s illustration. It is a slightly modified version of a map that Ruedemann published in the 1930s. Notice the prominent placement and labeling of the Lackawanna River. And then see how long he made the Lackawanna. Ruedemann meant his map to show local rivers as he thought they had been about a 100 million years ago. The East Branch of today’s Delaware River is what Ruedemann labeled at EB on his map. Ruedemann made it part of the Lackawanna. He does not label Batavia Kill but that is the eastern stretch of Ruedemann’s ancient Lackawanna.

Ruedemann had noticed how those three rivers all lined up so nicely. He hypothesized that they had once been joined together to form a very long Lackawanna. So, what changed all that? Why aren’t they all still joined? The villains in Ruedemann’s saga are the Delaware and the Hudson Rivers. The Delaware is the dotted line on the western part of his map. It, back then, was eroding its way north. It would get longer and longer until it intersected the old Lackawanna. Then it would divert much of that river. The upper Lackawanna became the East Branch of the now longer Delaware. The Delaware kept on eroding and eventually diverted the upper Susquehanna to make its West Branch.

River erosion like this is called headward erosion. The upper reaches, or heads of rivers, work their ways up into the hinterlands. If they encounter another river then they rob it of much of its flow. The word we geologists use for this sort of theft is “piracy.” Both the old Lackawanna and the old Susquehanna were pirated.

Ruedemann’s story is far from over. Look to the east on the map. Those eastern dotted lines are the Hudson and Mohawk Rivers, along with the Schoharie Creek. They too were the products of headward erosion. The Hudson, during the same span of time, had been eroding its way north. It gave birth to its tributary, the Mohawk, which, in turn, gave birth to its tributary, Schoharie Creek. And Schoharie Creek lopped off another large chunk of the old Lackawanna. That chunk is today the Batavia Kill drainage basin which flows right through Windham. That takes us back to the beginning of this column. The creek that flows through Windham used to be part of the Lackawanna River.

And that then gets us back to Carl Sagan. Did Ruedemann come up with enough extraordinary evidence to support his extraordinary claim? Well, to this day, that is something that they debate late at night in geology bars. Do we have our own opinions? Well, let’s just say that most couples fight over money. We are fond of Ruedemann’s ideas and we would like it if they turned out to be true. But even in the 1930s these ideas were conjectural. They can be, if one insists, dismissed as mere coincidence and who can say that is not so.

A longer version of this story will be in the author’s new book The Catskills, a Geological Guide, the expanded edition. Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.”

Into the Maze

On the Rocks – The Woodstock Times

Updated by Robert and Johanna Titus

Look at a good, detailed map of the Hudson Valley in the vicinity just east of West Saugerties and Manorville. If you focus on the streams long enough, you just might notice something odd. A series of rivers descends the Catskill Front. Plattekill Creek is the most prominent, but there are several others, mostly unnamed. They all start out fine, descending picturesque mountain canyons as typical mountain streams. Then something peculiar happens. They all enter into a confusing complex maze of streams. Almost all the rivers and their tributary systems display a prominent north-south orientation. Within that pattern there are a large number of abrupt left and right turns as well. That gives our drainage a lattice-like appearance. We have searched the geological lexicon and we are not exactly sure what this should be called, but we think “rectangular drainage” is the best choice. It’s a curious pattern and, of course, there’s a reason for all this.

It all has a lot more to do with the bedrock than the rivers. You see, throughout much of this area there are alternating layers of sandstone and shale. All these stratified rocks are inclined; they dip into the earth toward the west. What that means is that the crust was once actually moved, tilting to produce north-south ridges of very solid rock.

The bedrock geology has been like this for probably hundreds of millions of years, but in recent times there have been changes. A mere 15,000 years ago, the Hudson Valley glacier flowed south through the valley. The ice must have been several thousand feet thick, and it acted like a great sheet of sandpaper. The passing glacier eroded the bedrock. Naturally the ice has had little trouble scooping out the shales, they are so soft. But the ice had much more trouble with the sandstones. Tough as that stuff is, the glacier was still able to pluck loose large blocks of it and carry them off. The ice actually adheres to the rock and yanks it loose. That has sharpened and straightened the many ridges of sandstone.

All this leads us back to those rectangular river patterns. You see rivers have a very hard time getting through the ridges of sandstone, so they have followed the shales. They have eroded out their channels along the bands of the softer rock. Still, a Hudson Valley creek eventually has to east toward the Hudson River. So, from time to time, the creeks have found breaks in the sandstones and have worked their way through those ridges. That’s the origin of the sharp rectangular turns.

Plattekill Creek is typical. It is a gorgeous mountain stream as it drops out of the Catskills and passes through the village of West Saugerties. Everything continues well until it reaches the vicinity of Blue Mountain and the Saugerties Reservoir. There it abruptly makes a sharp south turn and follows a beeline in that direction for three miles. Here it is nestled between ridges of sandstone.

It’s in this vicinity that Plattekill Creek has entered that maze of tributaries. And it’s here where that north-south lineation of the drainage is best developed. We have worked the area and we believe that there are about 11 ridges of sandstone here. All of them offer barriers that can confine the tributaries into those north-south straightjackets. You can see some of these ridges and several more. Head east on Rte. 212 until you get to Shultis corner and the intersection with the Glasco Pike. From here, you can head east and count the ridges of rock that cross the pike. Or you can continue on Rte. 212 and count the ridges on your way toward Centerville. If you do count the ridges, don’t expect the numbers to come out the same. We get different numbers every time we take the route. Geology isn’t Physics and we don’t worry too much about exact numbers.

Plattekill Creek eventually has to cut through to the Hudson and it begins the hard part of its journey near where it is crossed by Rte. 212. Between here and its junction with the Glasco Turnpike, the Plattekill has to cut its way through the tough rocks of the Mount Marion ridge. In some stretches of this flow, the Plattekill has been forced to carve real canyons. You can take the Fish Creek Road north from High Woods and cross the Plattekill in this vicinity.

In the end, there is nothing all that special or mysterious about this maze of rivers. It’s just another among many landscape features, but a geologist does take a quiet satisfaction from noticing and understanding.

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

Into the Maze

On the Rocks – The Woodstock Times

Updated by Robert and Johanna Titus

Look at a good, detailed map of the Hudson Valley in the vicinity just east of West Saugerties and Manorville. If you focus on the streams long enough, you just might notice something odd. A series of rivers descends the Catskill Front. Plattekill Creek is the most prominent, but there are several others, mostly unnamed. They all start out fine, descending picturesque mountain canyons as typical mountain streams. Then something peculiar happens. They all enter into a confusing complex maze of streams. Almost all the rivers and their tributary systems display a prominent north-south orientation. Within that pattern there are a large number of abrupt left and right turns as well. That gives our drainage a lattice-like appearance. We have searched the geological lexicon and we are not exactly sure what this should be called, but we think “rectangular drainage” is the best choice. It’s a curious pattern and, of course, there’s a reason for all this.

It all has a lot more to do with the bedrock than the rivers. You see, throughout much of this area there are alternating layers of sandstone and shale. All these stratified rocks are inclined; they dip into the earth toward the west. What that means is that the crust was once actually moved, tilting to produce north-south ridges of very solid rock.

The bedrock geology has been like this for probably hundreds of millions of years, but in recent times there have been changes. A mere 15,000 years ago, the Hudson Valley glacier flowed south through the valley. The ice must have been several thousand feet thick, and it acted like a great sheet of sandpaper. The passing glacier eroded the bedrock. Naturally the ice has had little trouble scooping out the shales, they are so soft. But the ice had much more trouble with the sandstones. Tough as that stuff is, the glacier was still able to pluck loose large blocks of it and carry them off. The ice actually adheres to the rock and yanks it loose. That has sharpened and straightened the many ridges of sandstone.

All this leads us back to those rectangular river patterns. You see rivers have a very hard time getting through the ridges of sandstone, so they have followed the shales. They have eroded out their channels along the bands of the softer rock. Still, a Hudson Valley creek eventually has to east toward the Hudson River. So, from time to time, the creeks have found breaks in the sandstones and have worked their way through those ridges. That’s the origin of the sharp rectangular turns.

Plattekill Creek is typical. It is a gorgeous mountain stream as it drops out of the Catskills and passes through the village of West Saugerties. Everything continues well until it reaches the vicinity of Blue Mountain and the Saugerties Reservoir. There it abruptly makes a sharp south turn and follows a beeline in that direction for three miles. Here it is nestled between ridges of sandstone.

It’s in this vicinity that Plattekill Creek has entered that maze of tributaries. And it’s here where that north-south lineation of the drainage is best developed. We have worked the area and we believe that there are about 11 ridges of sandstone here. All of them offer barriers that can confine the tributaries into those north-south straightjackets. You can see some of these ridges and several more. Head east on Rte. 212 until you get to Shultis corner and the intersection with the Glasco Pike. From here, you can head east and count the ridges of rock that cross the pike. Or you can continue on Rte. 212 and count the ridges on your way toward Centerville. If you do count the ridges, don’t expect the numbers to come out the same. We get different numbers every time we take the route. Geology isn’t Physics and we don’t worry too much about exact numbers.

Plattekill Creek eventually has to cut through to the Hudson and it begins the hard part of its journey near where it is crossed by Rte. 212. Between here and its junction with the Glasco Turnpike, the Plattekill has to cut its way through the tough rocks of the Mount Marion ridge. In some stretches of this flow, the Plattekill has been forced to carve real canyons. You can take the Fish Creek Road north from High Woods and cross the Plattekill in this vicinity.

In the end, there is nothing all that special or mysterious about this maze of rivers. It’s just another among many landscape features, but a geologist does take a quiet satisfaction from noticing and understanding.

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

The Greenport Mastodon

Windows Through time; The Register Star; July 8, 2010

Updated by Robert and Johanna Titus

Our topic today is one of the most notable paleontological discoveries ever made here in our region: the discovery of the first mastodon. This was a big find and was made a long time ago: way back in 1705. That’s when a Dutch colonist found a huge tooth in a bank of clay along eastern bank of the Hudson in Greenport. It weighed almost five pounds, and our Dutchman must have been most impressed. Not so impressed, however, that he was not willing to sell it for a half gill of rum to a local assemblyman.

The tooth worked its way up the political food chain to Lord Cornbury, then Governor of the New York Colony. He sent it off to the Royal Society of London. Today, that would be like sending it to the Smithsonian Institute. The tooth attracted a lot of attention in London, and from just the right people.  n 1705 not much was known about prehistoric monsters, in fact very little was known about prehistory. The scientists of the time were puzzled.

There were two hypotheses. Some thought that the tooth belonged to a remarkable beast or fish, but they could not imagine what type of creature it had been.  Lord Cornbury and others had another idea; the tooth belonged to a “giant” and they were talking of a biblical giant, referred to in Genesis 6:4. This tooth had belonged to a huge human being!

To his credit Cornbury sent people to search the original site for more skeletal remains and they found parts of a very decomposed skeleton. It was estimated that the beast had been 70 feet long. In fact, they had greatly overestimated the beast, but you can imagine how they reacted to the very notion!

From the very beginning there were others who speculated that the remains belonged to an elephant, but what kind of an elephant and how did such an animal get to the Hudson Valley? For the second part of the question, here again, contemporary religious views offered a solution: the beast had been carried here by Noah’s Flood. That would be difficult to prove, but it was an appealing idea.

It would take decades to solve the other half of the problem – what kind of elephant had it been – and that came when many more mastodon bones were found in the Ohio River Valley and a complete skeleton was unearthed in New York’s Orange County. Now, at last, scientists could see a whole skeleton with tusks and, clearly, they were those of an elephant, or at least a distant cousin of today’s elephant. But only a distant cousin; now there was a new scientific problem.

The mastodon did not match the Indian or the African elephants; it was a separate and new species. But nobody had ever seen such a creature in the wild. That was still another problem. At this time the very notion of extinction was a new and very troubling concept. Could the mastodon have once lived and then gone extinct? Not many people were comfortable with that thought. Theologians, especially, argued that no such thing could have happened; God would not allow extinction of species he had created. Perhaps not, but if so, where were the living mastodons?

That was a serious scientific question in the early 1800’s and President Thomas Jefferson, a pretty accomplished amateur scientist in his own right, thought he could solve it. The Lewis and Clark expedition was soon to head west, and Jefferson specifically asked its members to be on the lookout for mastodons. Certainly, the animals were extinct here in the east, but perhaps they still lived somewhere out there beyond the Appalachians.

Well, Lewis and Clark found a lot of things all across America, but they never saw and elephant. The results were clear: mastodons were extinct and, like it or not, extinction was something that really could happen – and really had happened.

All this adds up to some very important early progress in the science of paleontology. Our Greenport mastodon was among the very first prehistoric monsters to be discovered. Later generations would find the dinosaurs, but these great mastodons are still quite something to contemplate. All this would lead, with time, to a great understanding of the exotic nature of our planet’s paleontological history; it was one of the first glimpses into life’s distant past.

But equally important was the introduction of the very concept of extinction. We take that for granted today but it was a most remarkable, and disturbing, discovery two centuries ago.

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