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2019-20 WINTER Landscapes

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Seasonal Sightings The view in Glacial Park from the top of the camelback kame. This spot is 75 feet above The view in Marengo Ridge by picnic shelter #2. This spot is on top of the terminal moraine left by Nippersink Creek valley. Imagine the glacier standing four to five times taller! the last advance of the Wisconsin glacier. Ice Cold by Education and Visitor Center Services Coordinator Kim Compton As we deal with the onset of our own winter season, take a few on the trail up the camelback kame. Once on the top of the kame, moments to think about what this area experienced during the Ice you are 75 feet above Nippersink Creek valley. Imagine the glacier Age that existed in northeastern Illinois from about 100,000 years standing four to five times taller! ago to 14,000 years ago. While that may seem like a long time ago, Marengo Ridge Conservation Area in Marengo is another good in geologic time it is considered recent, and there is still evidence place to see glacial remnants. At the picnic shelter overlooking of glacial remnants in McHenry County’s Conservation Areas today. the open prairie, you will be on top of the terminal Marengo At the aptly named Glacial Park in Ringwood, visitors can see both moraine. This ridge was the farthest the Wisconsin glacier kettles and kames. Kettles are depressions that were formed extended and at the ice’s edge, a long pile of till was dumped, when large chunks of ice broke off from the melting glacier and which formed the moraine. From this same viewpoint, the valley got left behind, buried under or surrounded by the sand and was formed when the Kishwaukee River, once a rushing force, took gravel carried by the meltwater. As the ice melted, depending on meltwaters beyond the moraine. the kettle, some drained completely and some became different The highest point in McHenry County is found kinds of wetlands or water bodies. In Glacial Park there is a dry on the Woodstock moraine, in an area where kettle, a kettle marsh and a kettle bog. To the second furthest advance of the Wisconsin see these landforms, walk along the marsh glacier pushed till up and over the existing loop. Get a great view of the kettle marsh terminal Marengo moraine. Visit High Point from the amphitheater and see the kettle Conservation Area in Harvard, follow the trail bog as you walk along the ridge between and look for the USGS marker on the top of the marsh and bog. The dry kettle is the USGS marker at High Point. the hill. p/c dundee85 picnic area down the hill from the kettle parking lot. In most of the District’s Conservation Areas, you may also run across boulders or bigger sized rocks that seem out of place. These Take the numbered interpretive trail or the are called glacial erratics and were plucked from the land and Deerpath trail to see the kames. There are carried along with the glacial ice. Granite, sandstone, basalt and several in the park but the tallest and the more could be from as far away as Hudson Bay! one with a trail over the top is called the Glacial till of the camelback kame. camelback kame. A kame is a cone-shaped Despite the passing of thousands of years, many remnants of the or small ridge of till that was carried along with the glacier until glaciers can be seen in your local Conservation Areas. Take some a crack formed in the glacier and the till spilled out in the shape time this winter to witness the results of the forces of nature that of the crack. Till is the gravel and sand that was plucked from the shaped our region. land by the glaciers and deposited elsewhere. Gravel is noticeable 14 Landscapes | Winter 2019-20 Sizing Up the IceEnvironmental Age Adventures When you think about the Ice Age, what comes to mind? Glaciers? Pre-historic animals? Cave men? Perhaps you just envisioned the animated movie. While we were not around to see the Ice Age first hand, we have evidence today of the incredible impact the glaciers had on our landscapes. Glacial Blanks Using the information on the previous page, see if you can fill in the blanks with the correct glacial terms. Use the word bank below and ask your parents for help too! • A is created when • Glacial deposits of sand, gravel and • Unsorted material sediment a glacier begins to retreat and leaves rock form irregularly shaped mounds deposited from glaciers is also behind blocks of ice buried under and hills. These large mounds and known as . sand and gravel. When the ice melts hills are known as . it creates this depression in the land. • A is a ridge-like WORD BANK • A is a large rock buildup of glacial debris that marks glacial erratic that is carried by the glaciers and is the place where the advance of the kames kettle eventually left behind. This piece of ice sheet stopped and dropped the terminal moraine bedrock rock differs from all the other till it had been carrying. till native rocks in the area. Answer Key: kettle; glacial erratic; kames; terminal moraine; till moraine; terminal kames; erratic; glacial kettle; Key: Answer Evidence Today While we can’t take you back in time to see the incredible glaciers, you can come out today to Glacial Park and Marengo Ridge Conservation Areas to see Make Your Own Kettle At Home! evidence of the glaciers that came through McHenry County. In Glacial Park, glacial kames are one of the Now that you know a little more about glacial formations, most obvious features left behind by these glaciers. try this next activity at home to get an idea of the actual Climb to the top of the kames and then imagine how process that formed glacial kettles. the glaciers would have been still 4 to 5 times higher What You Need: than where you are standing! Or head out to Marengo Ridge to see the ridge that was the terminal moraine for the last ice sheet to cover the county! A bowl, loose dry sand, an ice cube, a source of heat. Icons made by Smashicons, Freepik and Goodware Freepik and from Smashicons, www.flaticon.com by made Icons 1. Fill the bowl about halfway with loose dry sand. Try to make the sand as level as possible. 2. Partially bury an ice cube (the block of ice left behind by the glacier) in the center of the sand. 3. Put the bowl under some sort of heat source (the sun, or by a source of warmth). Watch as the ice cube (piece of glacier) starts to melt. As it melts, notice how it creates a depression in the sand. This depression would then fill with floodwaters from the glacier or from nearby floodplains. READING CORNER Wooly Mammoth by Mick Manning and Brita Granstrom; Prehistoric World: The Ice Age by Dougal Dixon; Magic Treehouse: Sunset of the Sabertooth by Mary Pope Osborne Landscapes | 15 Winter 2019-20.
Recommended publications
  • Disappearing Kettle Ponds Reveal a Drying Kenai Peninsula by Ed Berg

    Disappearing Kettle Ponds Reveal a Drying Kenai Peninsula by Ed Berg

    Refuge Notebook • Vol. 3, No. 38 • October 12, 2001 Disappearing kettle ponds reveal a drying Kenai Peninsula by Ed Berg A typical transect starts at the forest edge, passes through a grass (Calamagrostis) zone, into Sphagnum peat moss, and then into wet sedges, sometimes with pools of standing water, and then back through these same zones on the other side of the kettle. Three of the four kettles we surveyed this summer were quite wet in the middle (especially after the July rains), and we had to wear hip boots. These plots can be resurveyed in future decades and, if I am correct, they will show a succession of drier and drier plants as the water table drops lower and lower, due to warmer summers and increased evap- Photo of a kettle pond by the National Park Service. otranspiration. If I am wrong, and the climate trend turns around toward cooler and wetter, these plots will When the glaciers left the Soldotna-Sterling area be under water again, as they were on the old aerial some 14,000 years ago, the glacier fronts didn’t re- photos. cede smoothly like their modern descendants, such as By far the most striking feature that we have Portage or Skilak glaciers. observed in the kettles is a band of young spruce Rather, the flat-lying ice sheets broke up into nu- seedlings popping up in the grass zones. These merous blocks, which became partially buried in hilly seedlings can form a halo around the perimeter of a moraines and flat outwash plains. In time these gi- kettle.
  • WELLESLEY TRAILS Self-Guided Walk

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  • Introduction to Geological Process in Illinois Glacial

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    INTRODUCTION TO GEOLOGICAL PROCESS IN ILLINOIS GLACIAL PROCESSES AND LANDSCAPES GLACIERS A glacier is a flowing mass of ice. This simple definition covers many possibilities. Glaciers are large, but they can range in size from continent covering (like that occupying Antarctica) to barely covering the head of a mountain valley (like those found in the Grand Tetons and Glacier National Park). No glaciers are found in Illinois; however, they had a profound effect shaping our landscape. More on glaciers: http://www.physicalgeography.net/fundamentals/10ad.html Formation and Movement of Glacial Ice When placed under the appropriate conditions of pressure and temperature, ice will flow. In a glacier, this occurs when the ice is at least 20-50 meters (60 to 150 feet) thick. The buildup results from the accumulation of snow over the course of many years and requires that at least some of each winter’s snowfall does not melt over the following summer. The portion of the glacier where there is a net accumulation of ice and snow from year to year is called the zone of accumulation. The normal rate of glacial movement is a few feet per day, although some glaciers can surge at tens of feet per day. The ice moves by flowing and basal slip. Flow occurs through “plastic deformation” in which the solid ice deforms without melting or breaking. Plastic deformation is much like the slow flow of Silly Putty and can only occur when the ice is under pressure from above. The accumulation of meltwater underneath the glacier can act as a lubricant which allows the ice to slide on its base.
  • Model by Keven

    Model by Keven

    High-quality constraints on the glacial isostatic adjustment process over North America: The ICE-7G_NA (VM7) model by Keven Roy A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Graduate Department of Physics University of Toronto © Copyright 2017 by Keven Roy Abstract High-quality constraints on the glacial isostatic adjustment process over North America: The ICE-7G_NA (VM7) model Keven Roy Doctor of Philosophy Graduate Department of Physics University of Toronto 2017 The Glacial Isostatic Adjustment (GIA) process describes the response of the Earth’s surface to variations in land ice cover. Models of the phenomenon, which is dominated by the influence of the Late Pleistocene cycle of glaciation and deglaciation, depend on two fundamental inputs: a history of ice-sheet loading and a model of the radial variation of mantle viscosity. Various geophysical observables enable us to test and refine these models. In this work, the impact of the GIA process on the rotational state of the planet will be analyzed, and new estimates of the long-term secular trend associated with the GIA process will be provided. It will be demonstrated that it has undertaken a significant change since the mid-1990s. Other important observables include the vast amount of geological inferences of past sea level change that exist for all the main coasts of the world. The U.S. Atlantic coast is a region of particular interest in this regard, due to the fact that data from the length of this coast provides a transect of the forebulge associated with the former Laurentide ice sheet.
  • During the Last Ice Age As Ice Sheets Moved Southward Over Our Region, Glaciers Broke Off and Carried Pieces of the Underlying Bedrocks

    During the Last Ice Age As Ice Sheets Moved Southward Over Our Region, Glaciers Broke Off and Carried Pieces of the Underlying Bedrocks

    “Glacial Erratics and Fieldstones” Boulders and other rocks broken off and carried by ice sheets covering this region were left in place when the glaciers melted. Geologists call these “erratics.”. Early settlers called them “fieldstones” and used them to build their house walls. During the last Ice Age as ice sheets moved southward over our region, glaciers broke off and carried pieces of the underlying bedrocks. When the ice melted, the fragments were left scattered over the surface. Geologists call such transported rocks “glacial erratics,” because they are different from the native bedrock. Most of these were pebble- and boulder-sized, mixed into sands and clay. A few are more than 10 feet high, such as Haring Rock in the Tenafly Nature Center (Fig 1A) and Tripod Rock in Sussex County (Fig. 1b). Fig. 2 shows images of erratics of various sized in a state park. As the ice sheets moved, rocks underneath often scratched parallel grooves in the bedrocks. These are called “glacial striations” (Fig. 3). Until Englewood Township was formally organized in 1859, most of what is now our City consisted of small farms which stretched from Overpeck Creek uphill to the Hudson River. Like other early European settlers, the farmers needed to move the boulders and other glacial erratics to create plowable fields. Rocks were gathered to build stone walls typical of New England and other glaciated parts of the Northeast. (Fig. 4). Many of the stones collected from the fields (“fieldstones”) were trimmed to make the walls of homes and other buildings. Many of the remaining buildings from the Dutch/English colonial period and the early 19th Century here in Englewood and vicinity incorporated “fieldstones” in their walls.
  • The Climate of the Last Glacial Maximum: Results from a Coupled Atmosphere-Ocean General Circulation Model Andrew B

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    JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 104, NO. D20, PAGES 24,509–24,525, OCTOBER 27, 1999 The climate of the Last Glacial Maximum: Results from a coupled atmosphere-ocean general circulation model Andrew B. G. Bush Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Canada S. George H. Philander Program in Atmospheric and Oceanic Sciences, Department of Geosciences, Princeton University Princeton, New Jersey Abstract. Results from a coupled atmosphere-ocean general circulation model simulation of the Last Glacial Maximum reveal annual mean continental cooling between 4Њ and 7ЊC over tropical landmasses, up to 26Њ of cooling over the Laurentide ice sheet, and a global mean temperature depression of 4.3ЊC. The simulation incorporates glacial ice sheets, glacial land surface, reduced sea level, 21 ka orbital parameters, and decreased atmospheric CO2. Glacial winds, in addition to exhibiting anticyclonic circulations over the ice sheets themselves, show a strong cyclonic circulation over the northwest Atlantic basin, enhanced easterly flow over the tropical Pacific, and enhanced westerly flow over the Indian Ocean. Changes in equatorial winds are congruous with a westward shift in tropical convection, which leaves the western Pacific much drier than today but the Indonesian archipelago much wetter. Global mean specific humidity in the glacial climate is 10% less than today. Stronger Pacific easterlies increase the tilt of the tropical thermocline, increase the speed of the Equatorial Undercurrent, and increase the westward extent of the cold tongue, thereby depressing glacial sea surface temperatures in the western tropical Pacific by ϳ5Њ–6ЊC. 1. Introduction and Broccoli, 1985a, b; Broccoli and Manabe, 1987; Broccoli and Marciniak, 1996].
  • An Esker Group South of Dayton, Ohio 231 JACKSON—Notes on the Aphididae 243 New Books 250 Natural History Survey 250

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    The Ohio Naturalist, PUBLISHED BY The Biological Club of the Ohio State University. Volume VIII. JANUARY. 1908. No. 3 TABLE OF CONTENTS. SCHEPFEL—An Esker Group South of Dayton, Ohio 231 JACKSON—Notes on the Aphididae 243 New Books 250 Natural History Survey 250 AN ESKER GROUP SOUTH OF DAYTON, OHIO.1 EARL R. SCHEFFEL Contents. Introduction. General Discussion of Eskers. Preliminary Description of Region. Bearing on Archaeology. Topographic Relations. Theories of Origin. Detailed Description of Eskers. Kame Area to the West of Eskers. Studies. Proximity of Eskers. Altitude of These Deposits. Height of Eskers. Composition of Eskers. Reticulation. Rock Weathering. Knolls. Crest-Lines. Economic Importance. Area to the East. Conclusion and Summary. Introduction. This paper has for its object the discussion of an esker group2 south of Dayton, Ohio;3 which group constitutes a part of the first or outer moraine of the Miami Lobe of the Late Wisconsin ice where it forms the east bluff of the Great Miami River south of Dayton.4 1. Given before the Ohio Academy of Science, Nov. 30, 1907, at Oxford, O., repre- senting work performed under the direction of Professor Frank Carney as partial requirement for the Master's Degree. 2. F: G. Clapp, Jour, of Geol., Vol. XII, (1904), pp. 203-210. 3. The writer's attention was first called to the group the past year under the name "Morainic Ridges," by Professor W. B. Werthner, of Steele High School, located in the city mentioned. Professor Werthner stated that Professor August P. Foerste of the same school and himself had spent some time together in the study of this region, but that the field was still clear for inves- tigation and publication.
  • The History of Ice on Earth by Michael Marshall

    The History of Ice on Earth by Michael Marshall

    The history of ice on Earth By Michael Marshall Primitive humans, clad in animal skins, trekking across vast expanses of ice in a desperate search to find food. That’s the image that comes to mind when most of us think about an ice age. But in fact there have been many ice ages, most of them long before humans made their first appearance. And the familiar picture of an ice age is of a comparatively mild one: others were so severe that the entire Earth froze over, for tens or even hundreds of millions of years. In fact, the planet seems to have three main settings: “greenhouse”, when tropical temperatures extend to the polesand there are no ice sheets at all; “icehouse”, when there is some permanent ice, although its extent varies greatly; and “snowball”, in which the planet’s entire surface is frozen over. Why the ice periodically advances – and why it retreats again – is a mystery that glaciologists have only just started to unravel. Here’s our recap of all the back and forth they’re trying to explain. Snowball Earth 2.4 to 2.1 billion years ago The Huronian glaciation is the oldest ice age we know about. The Earth was just over 2 billion years old, and home only to unicellular life-forms. The early stages of the Huronian, from 2.4 to 2.3 billion years ago, seem to have been particularly severe, with the entire planet frozen over in the first “snowball Earth”. This may have been triggered by a 250-million-year lull in volcanic activity, which would have meant less carbon dioxide being pumped into the atmosphere, and a reduced greenhouse effect.
  • Hogback Trail Greenfield State Park Greenfield, New Hampshire

    Hogback Trail Greenfield State Park Greenfield, New Hampshire

    Hogback Trail Greenfield State Park Greenfield, New Hampshire Self-Guided Hike 1. The Hogback Trail is 1.2 miles long and relatively flat. It will take you approximately 45 minutes to go around the pond. As you walk, keep an eye out for the abundant wildlife and unique plants that are in this secluded area of the park. Throughout the trail, there are numbered stations that correspond to this guide and benches to rest upon. Practice “Leave No Trace” on your hike; Take only photographs, leave only footprints. 2. Hogback Pond is a glacial kettle pond formed when massive chunks of Stop #5: ridge is an example of glacial esker ice were buried in the sand, then slowly melted leaving a huge depression in the landscape that eventually filled with water. Kettle ponds generally have no streams running into them or out of them, resulting in a still body of water. Water in the pond is replenished by rain and is acidic, prohibiting many common wetland species from flourishing. 3. The blueberry bushes around Hogback Pond and throughout Greenfield State Park are two species; low-bush and high-bush. Many animals such as Black Bear and several species of birds seek out these berries as an important summer food source. Between Stops #2 & 3: example of unique vegetation found on kettle ponds 4. The Eastern Hemlocks that you see around you are one of the several varieties of evergreen that grow around Hogback Pond. This slow- growing, long-lived tree grows well in the shade. They have numerous short needles spreading directly from the branches in one flat layer.
  • Trip F the PINNACLE HILLS and the MENDON KAME AREA: CONTRASTING MORAINAL DEPOSITS by Robert A

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    F-1 Trip F THE PINNACLE HILLS AND THE MENDON KAME AREA: CONTRASTING MORAINAL DEPOSITS by Robert A. Sanders Department of Geosciences Monroe Community College INTRODUCTION The Pinnacle Hills, fortunately, were voluminously described with many excellent photographs by Fairchild, (1923). In 1973 the Range still stands as a conspicuous east-west ridge extending from the town of Brighton, at about Hillside Avenue, four miles to the Genesee River at the University of Rochester campus, referred to as Oak Hill. But, for over thirty years the Range was butchered for sand and gravel, which was both a crime and blessing from the geological point of view (plates I-VI). First, it destroyed the original land form shapes which were subsequently covered with man-made structures drawing the shade on its original beauty. Secondly, it allowed study of its structure by a man with a brilliantly analytical mind, Herman L. Fair­ child. It is an excellent example of morainal deposition at an ice front in a state of dynamic equilibrium, except for minor fluctuations. The Mendon Kame area on the other hand, represents the result of a block of stagnant ice, probably detached and draped over drumlins and drumloidal hills, melting away with tunnels, crevasses, and per­ foration deposits spilling or squirting their included debris over a more or less square area leaving topographically high kames and esker F-2 segments with many kettles and a large central area of impounded drainage. There appears to be several wave-cut levels at around the + 700 1 Lake Dana level, (Fairchild, 1923). The author in no way pretends to be a Pleistocene expert, but an attempt is made to give a few possible interpretations of the many diverse forms found in the Mendon Kames area.
  • Des Moines Lobe Retreated North- What It Means to Be Minnesotan

    Des Moines Lobe Retreated North- What It Means to Be Minnesotan

    Route Map Geology of the Carleton College Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors, and the GIS ¯ user community 1 Cannon River Cowling Arboretum 2 Glacial Landscapes 3 Glacial Erratics 4 Local Bedrock A Guided Tour 5 Kettle Hole Marsh College BoundaryH - Back IA Parking Glacial Erratic Cannon River Tour Route Other Trails 0250 500 1 000 Feet, 5 HWY 3 4 LOWER ARBORETUM 3 2 H IA 1 Arb Office HWY 19 UPPER Tunnel IA ARBORETUM under Hwy 19 Lower Lyman Recreation IA Center HALL AVE HALL West IA Gym Library Published 5/2016 Product of the Carleton College Cowling Arboretum. For more information visit our website: apps.carleton.edu/campus/arb or contact us at (507)-222-4543 Introduction Hello and welcome to Carleton College’s Cowling Arboretum. This 1 800 acre natural area, owned and managed by Carleton, has long been one of the most beloved parts of Carleton for students, faculty and community members alike. Although the Arb is best known for its prairie ecosystem, an amazing history full of thundering riv- ers, massive glaciers, and the journeys of massive boulders lies just below the surface. This geologic history of the Arb is a fascinating story and one that you can experience for yourself by following this 2 self-guided tour. I hope it’s a beautiful day for a walk hope and that you enjoy learning about the geology of the Arb as much as I did. The route for this tour is about three miles long and will take you 1-2 hours to complete, depending on your walking speed.
  • Eemian Interglacial Deposits at Haćki Near Bielsk Podlaski: Implications for the Limit of the Last Glaciation in Northeastern Poland

    Eemian Interglacial Deposits at Haćki Near Bielsk Podlaski: Implications for the Limit of the Last Glaciation in Northeastern Poland

    Geological Quarterly, 2002, 46 (1): 75-80 Eemian Interglacial deposits at Haćki near Bielsk Podlaski: implications for the limit of the last glaciation in northeastern Poland Stanisław BRUD and Mirosława KUPRYJANOWICZ Brud S. and Kupryjanowicz M. (2002) — Eemian Interglacial deposits at Haćki near Bielsk Podlaski: implications forthe limit of the last glaciation in northeastern Poland. Geol. Quart., 46 (1): 75-80. Warszawa. Pollen analysis was conducted on organic deposits on a kame ridge at Haćki in northeastern Poland. The deposits are referred to the Eemian Interglacial. Slope sediments only covered these Biogenic deposits. The glacigenic landforms therefore relate to the Wartanian Glaciation, and so this area has not been occupied By an ice sheet of the Vistulian Glaciation. Stanisław Brud, Institute of Geological Sciences, Jagiellonian University, Oleandry 2A, PL-30-063 Kraków, Poland, e-mail: [email protected]; Mirosława Kupryjanowicz, Department o f Botany, Institute o f Biology, University o f Białystok, Świerkowa 20b, PL-15-950 Białystok, Poland, e-mail: [email protected] (received: November 3, 2000; accepted: February 26, 2001). Key words: NE Poland, Wartanian Glaciation, Eemian Interglacial, Vistulian, kames, pollen analysis. INTRODUCTION (Mojski, 1969) (Fig. 2). This deglaciation consisted of gradual reduction in ice sheet thickness, its dismembering into individ­ ual dead ice blocks, and their further melting. The most com­ mon landforms occurring north of Bielsk Podlaski are kames Numerous sites with biogenic deposits have Been found (Mojski and Nowicki, 1961). They rise from a few to aBout a during geological mapping of the Bielsk Podlaski sheet De­ dozen metres above melt-out depressions, marking an accumu­ tailed Geological Map of Poland, 1:50 000 scale.