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A fossil tree on an ancient trail

The Catskills Geologists; The Mountain Eagle

Robert and Johanna Titus

Dec. 13, 2018

We get a lot of email from our readers and sometimes they send us good leads on potential columns. That happened recently when a reader sent us a photo of a fossil that he found along the trail that leads up to Kaaterskill Falls. Have you been on that trail? It’s been there forever but has been nicely renovated in recent years. It makes a scenic hike. It’s not a difficult one and you are rewarded with a view of Kaaterskill Falls from below. That’s the view that Thomas Cole made famous with one of his first truly successful paintings done in the 1820’s. That view was important in the history of American art itself. If you haven’t been there, then you should.

We have hiked the trail many times and never tire of it. We haven’t had a whole lot of success in finding fossils along it, but they are there. If you have a sharp eye and if your eye is a trained one, then you do find the occasional fossil plant. These are trees from the famed Gilboa Forest. Those are New York Sate’s most important fossils; they make up the world’s oldest known forest ecology, dating back about 380 million years.

We know! We know! December is not a very good time of the year to go fossil hunting, but when the weather warms up, you might give it a try. We, ourselves, have found some fairly decent fossil tree trunks in the massive sandstones of Bastion Falls. That’s right above the highway at the hairpin turn on Rte. 23A. Maybe you can do us one better.

Our reader did just that. He found the branch of a fossil tree, complete with a row of leaves. Take a look at his photo. We immediately recognized the specimen. We had

already seen a very similar specimen in Bearsville. One of our Woodstock Times readers had found it in a quarry above her home. Take a look at our second photo for that one which is a much better–preserved fossil. See how much better the leaves look. We thought that both specimens belonged to a tree named Archaeopteris, but we wanted to be sure. So, we sent both photos off to friend Dr. Charles Ver Straeten at the New York State Museum. Chuck sent them on to two of the most foremost experts on Gilboa trees. They both agreed that these were specimens of Archaeopteris.

Archaeopteris is an important plant in the history of the evolution of trees. It belongs to a group called the progymnosperms.  That is a group of trees just a little more primitive than the gymnosperms themselves. And, as you might know, the gymnosperms include all of the modern evergreens; this is an important group of trees in the history of life.

The trail at Kaaterskill Falls is a scenic one for everyone who enjoys the outdoors, but for the two of us, it takes us back through time to an earlier planet Earth which was witnessing the rapid evolution of trees and of forests themselves.

Do you have good photos of geological wonders? Send them along with descriptions and perhaps we will be able to use them in a future column.

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

Brachiopods

The Catskill Geologists; May 25, 2018

Robert and Johanna Titus

If you do a lot of fossil hunting in the Catskills then you probably already know much about what we will be writing this week. But, even if you do, you may well find our column worth reading. It’s about a group of invertebrate shellfish that lived right here. And we mean right here. Look around you. Where you are now was once the bottom of an ocean called the Catskill Sea. That sea takes us back roughly 400 million years ago to the Devonian time period. Now take a look at our photo; it’s a piece of sandstone. Its flat surface is a petrified bit of that sea floor. And, just as it was hundreds of millions of years ago, it is littered with shellfish, now fossils. They are brachiopods. We see them on this rock – right where they lived and right where they died.

These animals, in life, lived within two shells so you might be tempted to call them clams. The similarity to clams is accidental. Brachiopods are a very different group of animals. Their internal, soft anatomy is entirely different from that of clams. Brachiopods are not even mollusks. We have blown up the image of one of these brachiopods in our second photo. Notice that there is a plane of symmetry running down the center of the shell. With clams there are also planes of symmetry but they are found in between the shells, not down their centers. Using symmetry you can always quickly tell apart clams from brachiopods. All this is important because these two groups are the most common fossils found in the deposits of the Catskill Sea. You need to know the difference. With experience that will soon become second nature.

All but one of these fossils belongs to a form of brachiopods called Mucrospirifer. Mucrospirifer shells are categorized by their heavy ridges and those two – tapering left and right – extensions, sometimes informally called “wings.” Mucrospirifer is a very common brachiopod in our region’s marine sedimentary rocks. It enjoyed great success during the Devonian. There is a second species of brachiopod in the upper right corner of our photo. It too has a plane of symmetry running down the center of its shell.

There are more things that need to be explained here. First, notice how many Mucrospirifers are seen on this bit of that ancient sea floor. And also notice that they are all just about the same size. We are guessing that this represents something that is common among marine invertebrate animals. Such creatures commonly begin life as single fertilized cells, zygotes that were cast out by their mothers. Alternatively, they may have been early and primitive larva. But in the end it was all the same; these very young invertebrates drifted with seafloor currents until they detected a suitable ecology and, then and there, they settled to the bottom and began their lives. A group of invertebrates of this sort, all the same size, is called a spatfall.

Another thing about these spatfalls is that they seem to us to be commonly found on very dark shales. Geologists generally assume that dark shales represent a quiet sea floor with a low oxygen content. If so, then much of the success of Mucrospirifer came from its ability to survive in a wide variety of environments, places that other animals found inhospitable.

But, in the end, what is important here is for you to learn about a common form of fossil, typical of our Catskills. Don’t your feel just a little smarter now that you have read our column?

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

Glaciers at the Arboretum

The Catskill Geologists

Robert and Johanna Titus

Have you been to the Mountain Top Arboretum? It’s in Onteora Park along Rte. 23C. The Arboretum was founded only about a quarter century ago and we have been members most of that time. It’s spread out across a couple of hundred acres of land, but the core is where the trees of the proper arboretum are, right by the road. They are young and not all that tall yet, but they are coming along.

We will be taking you there to see the geology from time to time, but let’s make our first visit today. If you visit the Arboretum you will be likely be parking in the lot right next to Rte. 23C. Right across from the parking lot, you will see the entrance to the main arboretum. There is a gate there and you can’t enter without passing through it. That’s where the geology starts.

If you look down, then you will see a flat surface of bedrock (our first photo). Look again and notice how that bedrock seems to have been smoothed out. It almost looks polished; it has been. Now look again and you will likely soon notice a series of long, very straight scratches in the rock. They are, all of them, parallel to each other. We always bring a compass along and we got it out and took some measurements. We found that all those scratches lie on a north-to-south lineation.

We had just begun a journey into the past; we were visiting the Ice Age. All that polishing was the result of a glacier passing across this surface.  The bottom of that moving ice was dirty with sand, silt and clay. The ice pressed all that sediment into the ground and polished that surface. Sanded might be a better choice of words. In any case, it was the ice that produced what we see here. If you look through the gate, you will be looking north. That’s the direction from which the glacier arrived. In our mind’s eyes we could look that way and envision that glacier moving towards us.

We have seen surfaces like this many times before. But what surprised us, and what we want to talk about today was something else. Off on the right side of this outcrop we saw a pair of what are called glacial grooves. So far, we have been talking about cobbles being dragged across the surface of the bedrock. These are very good at leaving striations. But, imagine for a moment that some very large boulders were being dragged by too. You would expect them to be pressed into the ground as much or more as nearby cobbles.

Those boulders, as you would expect, were making something bigger than striations; we call them glacial grooves. Grooves are a lot wider and deeper than striations. But there is something else. Those boulders were being pressed down by the weight of the ice. That tended to hold them in place. But they were also being pushed from behind by the moving ice. For a period of time the weight of the ice did hold these boulders in place, but then the push from behind got to be so great that the boulder skipped forward in a sudden leap. When it “landed,” it created a large crescentic nick in the surface of the bedrock. We call such nicks chattermarks.

This process continued for some time. Every “leap” forward left a new chattermark, all of them nicely nested in the boulder’s groove (our second photo). That’s what we see at the Arboretum and we don’t remember ever seeing any grooves quite as good as these. They are well worth a visit.

There is one problem with today’s story. If the sunlight is just right, then you will be able to see all that we have described. But if the light is wrong . . . then you will see none of it.

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

The Davenport Delta

The Catskill Geologists; The Mountain Eagle

Robert and Johanna Titus

Mar. 23, 2018

Did you ever take a good earth science course – in high school or college? Well, one of the things that commonly comes up is the structure of a delta. Deltas form when rivers or creeks flow into bodies of still water, oceans and lakes. The flowing water currents almost always carry a fair amount of sediment in them. That’s mostly sand, silt and clay. When those currents enter into a lake or ocean they generally slow down. Slow currents can’t carry as much sediment, so a lot of it gets deposited in the form of a delta.

Large rivers, flowing into oceans, tend to form large deltas. Think of the Mississippi Delta. Small creeks, flowing into your town’s skating pond, create small deltas. Big or little, deltas all have pretty much the same basic structure. The advancing front of the delta displays a steep slope that forms the delta’s outer edge. The sediments of this part of the delta display an inclined stratification. Those strata dip toward the lake bottom. The top of the delta receives sediments that are deposited on a flat plane. Those strata are horizontal.

Those inclined strata are called the foreset beds and, on top of them, are the horizontal strata of the topset. The adjacent lake bottom or sea floor, just beyond the foreset, receives a little more sediment, again deposited in flat stratified horizons. These are the bottomset deposits.

Well, in the end, a delta has a flat topset, a flat bottomset and a relatively steeply sloping foreset in between. Here’s the problem; deltas are underwater so we can’t see any of this. But, what if the lake drains, sometime after deposition of the delta? Then that delta would be left high and dry. We can read your minds right now: how can such a thing happen. Lakes don’t drain away, so the deltas will never be visible. Right?

Maybe – or maybe not.

Take a good look at our photo. It was taken just a short distance east of Davenport Center, looking north along Rte. 23. Close to the center of the photo is a house. Notice that behind it, to the left, is a flat surface. Just to its right is a relatively steep slope. At the bottom of that slope is another flat surface (almost hidden by trees). If you didn’t know better you might think that, arrayed right to left, was the bottomset, the foreset and the topset of a delta. But, of course, that can’t be, can it?

Well, if this is not a delta, then it is one remarkable imitation of one. We have a lot of explaining to do, don’t we? That supposed bottomset deposit, is a flat surface that extends quite some distance off to the east. We have done a little exploring there. Whenever we have climbed down to reach this “bottomset” we bring along a barbeque skewer. A what? Yes, a barbeque skewer; it is a very valuable piece of equipment when we are studying ice age deposits.

We drop down onto what we think is an ice age lake bottom and we try to drive the skewer into the ground. If it slides in easily then we know that there are no cobbles or pebbles in the ground. That is typical of lake bottom sediments. We try again with the skewer, and then again and again. If our skewer keeps sliding in, time after time, then we can assume that our flat surface is indeed the bottom of an ice age lake. That’s always a fun discovery. And, better still, this one was a lake with a delta.

Most of the Charlotte Creek Valley was dammed by melting glaciers at the end of the Ice Age. Lakes formed behind these ice dams and so it was that deltas, from time to time, formed in these lakes. We have discovered one of these old deltas. If you have a chance, go there and take a look; see the landscape there as we do.

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

Frozen in time

The Catskill Geologists; The Mountain Eagle; Nov. 30, 2023

Robert and Johanna Titus

Frozen in time is a common enough phrase. It usually refers to people or cultures who have not kept up with changes. Time goes by and changes come along, and those people and those cultures stay the same, stuck in the same old rut. Being frozen in time has a bit of a negative connotation. It happens when we just can’t change with time-or perhaps we don’t want to.

That time-worn old phrase leaped into our minds recently when we were up at the Mountain Top Arboretum. To geologists the notion of being frozen in time has a very different, even a professional meaning. We had been wandering the grounds at the Arboretum when we encountered an outcrop of typical Devonian aged Catskill sandstone. Are you familiar with the Arboretum? We are talking about the southeast corner of what is called the West Meadow. Usually seeing such rock is pretty routine and hardly very exciting, but this was different.

Take a look at our photo. Notice that the strata on the right dip to the right while those on the left dip in the opposite direction. What’s going on here? Well, we were looking at clues and were able to conjure up images of the distant past, a past that had given birth to our sandstone. These left- and right-leaning strata are said to be cross-bedded, actually the technical term is trough cross-bedded. That happens in modern river channels. On the deep, outer side of a wandering stream, the currents flow their fastest. When there are heavy rains, then the stream speeds up some more. It becomes erosional and scours out small channels, troughs, in the channel sands. At the end of the flood those currents slow down.  That’s when the stream loses its ability to carry sediment, most of it being sand, and a depositional event follows. Sand fills in the troughs and is stratified in a fashion that is parallel to those scours – sometimes left leaning, sometimes right.

You wait a few million years, and all this hardens into stratified sandstone. Then you wait a few hundred million years more and that sandstone is exposed by the slow and steady processes of erosion. Well, that sums up what happened at the Arboretum and that is how we saw it. But then we got just a little philosophical. We began to ponder what we were looking at.

We were looking into the distant past. We were looking at the floor of a stream that had once flowed by here, across the top of something called the Catskill Delta. And we were looking at a moment in time. This was, essentially, an instant in time. All that sediment had been deposited right there and right at that moment. If any of those sand grains had a mind of its own, then it would have thought that there was no reason why another flood should not come along, sweep it up and carry it off to the nearest ocean.

And that is, in fact, what usually happens. Almost all grains of sediment are destined to enter an ocean and become part of the sediment there. Go to the Jersey shore and pick up a single grain of sand on the beach. There is a very good chance that your sand grain came from the Catskills and had traveled down the Hudson.

But not with our sand grains at the Mountain Top. They had become “frozen in time.” Their river channel deposits had come to be buried by more sediments – and then even more – thousands of feet more. All of this had hardened into the sedimentary rocks of the Catskills. Our mountains are an ancient delta deposit – frozen in time.

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

What is Bluestone?

The Catskill Geologists; The Mountain Eagle 10-16-18

Robert and Johanna Titus

It would be hard to find a topic more emblematic of the Catskills than bluestone. It’s a stone that has been quarried hereabouts for nearly two centuries. It has mostly been fashioned into sidewalk slabs, but it has a large number of other uses as well. You can probably easily conjure up images of bluestone sidewalks in your mind’s eyes; there are so many of them still around. Then, you can probably also recognize buildings and churches made of the stuff. But just what is bluestone?

Bluestone is composed of large slabs of sandstone. Those sandstones are horizontally stratified, and, because of that, brawny quarrymen were able to excavate it and, using large sledge hammers and chisels, break it into those slabs. These were then shipped off to locations all over the eastern United States. Bluestone sidewalks last very long amounts of time. Also, they were skid resistant when it rained and, we think, very good looking. No wonder they were so popular. Are bluestones truly blue? We have always had a hard time finding bluestone that actually is “blue.” We understand that whatever blue there is comes from some of the clays that make up small components of these sandstones.

But, we still haven’t answered the question “what are bluestones.” Doing that means that we will have to travel back in time about 380 million years and visit the Catskills region as it was back then. It you have been reading our columns then you know that this was the Devonian time period and, back then, the Catskills region was an enormous delta. Rivers flowed across this, the Catskill Delta, and sands were deposited in their channels.

Flowing water picks up sand and moves it along. Depending on exactly where in the channel those flows are, governs just how fast the currents flow. Typically, one side of the stream sees the fastest flow while the other witnesses the slowest. Strata on the fast-flowing side are recognizably different from those of the slow side. We should talk about those deposits in future articles, but our focus today is on the middle of those petrified streams; that’s where the bluestone formed.

The middle of those Devonian streams accumulated those flat lying strata of sands. It was those that eventually hardened into the flat lying strata that make good bluestone. Some of those streams were a lot bigger than others. It was the largest of those streams that accumulated deposits thick enough to form bluestones that were commercially valuable.

Bluestone quarries were developed all across our mountains, but they were especially common in the Eastern Catskills. Quarrying was most active in the late nineteenth and early twentieth centuries. All the old, abandoned quarries are still there and they provide geologists with wonderful keyholes into our mountains’ Devonian past. We enjoy visiting them and exploring what they have to show us.

There still is an active bluestone industry but is mostly in the western parts of Sullivan County.

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

The Davenport Delta

The Catskill Geologists; Robert and Johanna Titus

The Mountain Eagle; Mar. 23, 2018

Did you ever take a good earth science course – in high school or college? Well, one of the things that commonly comes up is the structure of a delta. Deltas form when rivers or creeks flow into bodies of still water, oceans and lakes. The flowing water currents almost always carry a fair amount of sediment in them. That’s mostly sand, silt and clay. When those currents enter into a lake or ocean they generally slow down. Slow currents can’t carry as much sediment, so a lot of it gets deposited in the form of a delta.

Large rivers, flowing into oceans, tend to form large deltas. Think of the Mississippi Delta. Small creeks, flowing into your town’s skating pond, create small deltas. Big or little, deltas all have pretty much the same basic structure. The advancing front of the delta displays a steep slope that forms the delta’s outer edge. The sediments of this part of the delta display an inclined stratification. Those strata dip toward the lake bottom. The top of the delta receives sediments that are deposited on a flat plane. Those strata are horizontal.

Those inclined strata are called the foreset beds and, on top of them, are the horizontal strata of the topset. The adjacent lake bottom or sea floor, just beyond the foreset, receives a little more sediment, again deposited in flat stratified horizons. These are the bottomset deposits.

Well, in the end, a delta has a flat topset, a flat bottomset and a relatively steeply sloping foreset in between. Here’s the problem; deltas are underwater so we can’t see any of this. But, what if the lake drains, sometime after deposition of the delta? Then that delta would be left high and dry. We can read your minds right now: how can such a thing happen. Lakes don’t drain away, so the deltas will never be visible. Right?

Maybe – or maybe not.

Take a good look at our photo. It was taken just a short distance east of Davenport Center, looking north along Rte. 23. Close to the center of the photo is a house. Notice that behind it, to the left, is a flat surface. Just to its right is a relatively steep slope. At the bottom of that slope is another flat surface (almost hidden by trees). If you didn’t know better you might think that, arrayed right to left, was the bottomset, the foreset and the topset of a delta. But, of course, that can’t be, can it?

Well, if this is not a delta, then it is one remarkable imitation of one. We have a lot of explaining to do, don’t we? That supposed bottomset deposit, is a flat surface that extends quite some distance off to the east. We have done a little exploring there. Whenever we have climbed down to reach this “bottomset” we bring along a barbeque skewer. A what? Yes, a barbeque skewer; it is a very valuable piece of equipment when we are studying ice age deposits.

We drop down onto what we think is an ice age lake bottom and we try to drive the skewer into the ground. If it slides in easily then we know that there are no cobbles or pebbles in the ground. That is typical of lake bottom sediments. We try again with the skewer, and then again and again. If our skewer keeps sliding in, time after time, then we can assume that our flat surface is indeed the bottom of an ice age lake. That’s always a fun discovery. And, better still, this one was a lake with a delta.

Most of the Charlotte Creek Valley was dammed by melting glaciers at the end of the Ice Age. Lakes formed behind these ice dams and so it was that deltas, from time to time, formed in these lakes. We have discovered one of these old deltas. If you have a chance, go there and take a look; see the landscape there as we do.

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

A fossil tree on an ancient trail

The Catskills Geologists; The Mountain Eagle

Robert and Johanna Titus

Dec. 13, 2018

We get a lot of email from our readers and sometimes they send us good leads on potential columns. That happened recently when a reader sent us a photo of a fossil that he found along the trail that leads up to Kaaterskill Falls. Have you been on that trail? It’s been there forever but has been nicely renovated in recent years. It makes a scenic hike. It’s not a difficult one and you are rewarded with a view of Kaaterskill Falls from below. That’s the view that Thomas Cole made famous with one of his first truly successful paintings done in the 1820’s. That view was important in the history of American art itself. If you haven’t been there, then you should.

We have hiked the trail many times and never tire of it. We haven’t had a whole lot of success in finding fossils along it, but they are there. If you have a sharp eye and if your eye is a trained one, then you do find the occasional fossil plant. These are trees from the famed Gilboa Forest. Those are New York Sate’s most important fossils; they make up the world’s oldest known forest ecology, dating back about 380 million years.

We know! We know! December is not a very good time of the year to go fossil hunting, but when the weather warms up, you might give it a try. We, ourselves, have found some fairly decent fossil tree trunks in the massive sandstones of Bastion Falls. That’s right above the highway at the hairpin turn on Rte. 23A. Maybe you can do us one better.

Our reader did just that. He found the branch of a fossil tree, complete with a row of leaves. Take a look at his photo. We immediately recognized the specimen. We had

already seen a very similar specimen in Bearsville. One of our Woodstock Times readers had found it in a quarry above her home. Take a look at our second photo for that one which is a much better–preserved fossil. See how much better the leaves look. We thought that both specimens belonged to a tree named Archaeopteris, but we wanted to be sure. So, we sent both photos off to friend Dr. Charles Ver Straeten at the New York State Museum. Chuck sent them on to two of the most foremost experts on Gilboa trees. They both agreed that these were specimens of Archaeopteris.

Archaeopteris is an important plant in the history of the evolution of trees. It belongs to a group called the progymnosperms.  That is a group of trees just a little more primitive than the gymnosperms themselves. And, as you might know, the gymnosperms include all of the modern evergreens; this is an important group of trees in the history of life.

The trail at Kaaterskill Falls is a scenic one for everyone who enjoys the outdoors, but for the two of us, it takes us back through time to an earlier planet Earth which was witnessing the rapid evolution of trees and of forests themselves.

Do you have good photos of geological wonders? Send them along with descriptions and perhaps we will be able to use them in a future column.

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

Standing stones – Wisdom of the crowd?

The Mountain Eagle – The Catskill Geologists

Robert and Johanna Titus – Oct 26, 2018

Have you ever seen the Devil’s Tombstone? It’s quite a rock—located at Devil’s Tombstone Campground on Rte. 214 near Stony Clove. It’s right next to the highway and there is good parking, so it is easy to get to. Its peculiar name is easy to explain; the rock looks so much like a very large tombstone. However, we doubt that the Devil is buried there.

Such a rock is often called a monolith. It must be about ten feet tall and a few feet thick. It is composed of typical Catskills bluestone. These strata were once sands at the bottom of a Devonian aged river channel. Now these strata make up a boulder, standing on end. But, what exactly is the Devil’s tombstone? It seems that there should be a story here. Well, actually there are several stories. The first one is the most obvious; it is the notion that humans lifted the rock into its current vertical inclination—perhaps for religious or astronomical reasons.

The monolith notion is what scientists call a hypothesis. A hypothesis is an idea which has been advanced as a possible explanation for a scientific problem. A hypothesis needs to be tested through further observations. As more is learned, a hypothesis begins to look better or, if things go poorly, it can become falsified. After being sufficiently tested, a hypothesis may be elevated in science to the level of scientific theory. In science, the word carries a great deal of worth; a theory is considered the highest level of proof in science; it is viewed with great confidence.

But, in science, it is always thought that many hypotheses are better than just one.  The more, the better. What about the Devil’s Tombstone? Are there other hypotheses or is the human monolith concept the only one? There is at least one other; boulders of this sort can be the products of ice age activities. Advancing glaciers can be easily imagined as picking up and shoving forward boulders of this size. When a glacier reaches its farthest advance, it will halt and, sometime later, begin melting away. A boulder can be left behind, lying in any inclination. Many will lie at angles less than 90 degrees, but a few, logic tells us, should indeed, be at 90 degrees.

So, which is it? Were standing stones all or mostly all put in place by humans or were all or most of them bulldozed and dropped in place by glaciers? Well, before we decide, we have to learn as much as possible about standing stones and that’s where you come in. Do you know of any standing stones? Can you tell us where to go and see them? Do you know of any leaning stones? We need to see these too; in fact, those may be of more importance.

When we know about these boulders, then we can visit them and ascertain their geologic context. If all of them were found with glacial deposits called moraines, then that would be an indication an ice age origin. If most or all, lie outside of glacial deposits then that would be consistent with the human origin hypothesis.

The point is that all of you can find more of them than just the two of us. When we have a lot of them to look at, then we can gather enough evidence to make a good, sound conclusion—a theory.

So, think about it, we need your help.

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

National Fossil Day

The Catskill Geologists; The Mountain Eagle

Robert and Johanna Titus

Oct. 19, 2018

An event of some importance to the two of us is coming up soon. That’s National Fossil Day. That’s Wednesday, Oct. 17^th. It is primarily sponsored by the National Park Service, but it is also co-sponsored by about 270 other groups. The purpose is to “promote the scientific and educational value of fossils.” Hundreds of events are scheduled all across the country.

Let’s make you and “The Catskill Geologists” into group number 271. We have pondered what would be the most significant Catskills fossil and the choice was obvious. Our pick is something, a fossil plant, called a pseudosporochnalean cladoxylopsid. It’s also known to scientists as Eospermatopteris.” Those words are jawbreakers and so it won’t surprise you to find out that the plant is commonly referred to as “the Gilboa tree.”

The Gilboa tree was, of course, first discovered in Gilboa. That was back in the nineteenth century, but many more were found during excavations associated with the building of the Gilboa dam in the 1920’s. Those discoveries were of the stumps of about 200 trees. They were immediately recognized as being some of the most primitive trees known to science and their discovery generated a lot of excitement. Unfortunately, only the stumps were found. Those trees had apparently been growing along the banks of Devonian aged streams on something called the Catskill Delta. Floods deposited sands which buried and preserved those stumps. The middle and upper reaches of the trees were not buried and subsequently those parts decayed away. That was during the Devonian time period, about 380 million years ago.

What kind of tree, exactly, was the Gilboa fossil? Without any preserved foliage from the upper tree, nobody could tell. For about 80 years or so, this was one of the big mysteries of paleontology. Everybody understood that they were among the earliest and most primitive trees.  Everybody also understood that an important discovery was needed. If good foliage was found then, it was argued, we could determine just exactly what our planet’s earliest trees were.

That discovery came in an eastern Catskills quarry just years ago. Researchers from the New York State Museum were conducting a routine survey of the area when they stumbled across fossil foliage on a horizon of rock at the bottom of the quarry. The discovery was a bit of a disappointment because the foliage was so exotic and so primitive that we still don’t really know what kind of tree it is.

We would like it if you celebrated National Fossil Day by training your eyes to be alert for fossils in the rocks that you routinely pass by. Gilboa forest fossils are out there. But, we think it highly unlikely that you will encounter the foliage. So, let’s talk about what you might find on a good day—a very good day. And that discovery would be one of those tree stumps. We found one about 20 years ago and we include a photograph of it.

This seems to us, to be a very primitive stump. It lacks the sort of extensive root system that modern trees have. We look at it and are reminded of the bottoms of the stems of many mushrooms. How could this primitive tree have stood tall on windy days? We don’t know.

Well, take a good look and keep this image in mind. If you enjoy walking along Catskills streams, or through Catskills quarries, then you just might spot one of these. If you do, please send us a photo.

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