A dune is a landform composed of wind- or water-driven sand. It typically takes the form of a mound, ridge, or hill. An area with dunes is called a dune system or a dune complex. A large dune complex is called a dune field, while broad, flat regions covered with wind-swept sand or dunes, with little or no vegetation, are called ergs or sand seas. Dunes occur in different shapes and sizes, but most kinds of dunes are longer on the stoss (upflow) side, where the sand is pushed up the dune, and have a shorter slip face in the lee side. The valley or trough between dunes is called a dune slack.
Lake Michigan is one of the five Great Lakes of North America. It is the second-largest of the Great Lakes by volume and the third-largest by surface area, after Lake Superior and Lake Huron. To the east, its basin is conjoined with that of Lake Huron through the 3+1⁄2-mile (5.6-kilometer) wide, 295-foot deep Straits of Mackinac, giving it the same surface elevation as its easterly counterpart; the two are geologically a single lake.
Singing sand, also called whistling sand, barking sand or singing dune, is sand that produces sound. The sound emission may be caused by wind passing over dunes or by walking on the sand.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
Indiana Dunes National Park is a United States national park located in northwestern Indiana managed by the National Park Service. It was authorized by Congress in 1966 as the Indiana Dunes National Lakeshore and was redesignated as the nation's 61st national park on February 15, 2019. The park runs for about 20 miles (32 km) along the southern shore of Lake Michigan and covers 15,349 acres (6,212 ha). Along the lakefront, the eastern area is roughly the lake shore south to U.S. 12 or U.S. 20 between Michigan City, Indiana, on the east and the Cleveland-Cliffs steel plant on the west. This area's conservation scheme is enhanced by the older Indiana Dunes State Park. To the west of the steel plant lies West Beach and a small extension south of the steel mill continues west along Salt Creek to Indiana 249. The western area is roughly the shoreline south to U.S. 12 between the Burns Ditch west to Broadway in downtown Gary, Indiana. In addition, there are several outlying areas, including Pinhook Bog, in LaPorte County to the east; the Heron Rookery in Porter County, the center of the park; and the Calumet Prairie State Nature Preserve and the Hobart Prairie Grove, both in Lake County, the western end of the park.
A ridge is a long, narrow, elevated geomorphologic landform, structural feature, or a combination of both separated from the surrounding terrain by steep sides. The sides of a ridge slope away from a narrow top, the crest or ridgecrest, with the terrain dropping down on either side. The crest, if narrow, is also called a ridgeline. Limitations on the dimensions of a ridge are lacking. Its height above the surrounding terrain can vary from less than a meter to hundreds of meters. A ridge can be either depositional, erosional, tectonic, or a combination of these in origin and can consist of either bedrock, loose sediment, lava, or ice depending on its origin. A ridge can occur as either an isolated, independent feature or part of a larger geomorphological and/or structural feature. Frequently, a ridge can be further subdivided into smaller geomorphic or structural elements.
An ice volcano is a conical mound of ice formed over a terrestrial lake via the eruption of water and slush through an ice shelf. The process is wave-driven, with wind providing the energy for the waves to cut through the ice and create formations that loosely mimic the shape and activity of volcanoes. After being ejected into the atmosphere, the liquid water and slush freeze and fall back to the surface, growing the formation. Ice may also be erupted. The phenomenon is most often observed along the southern coast of Lake Erie and Lake Ontario, when the temperature is below freezing and the wind blows onshore with a velocity of at least 25 mph (40 km/h). They are known to reduce coastal erosion there. The formations are temporary: they are frequently destroyed by storms and warm weather, and once the lake wholly freezes over, eruptions are no longer possible.
Indiana Dunes State Park is an Indiana State Park located in Porter County, Indiana, United States, 47 miles (75.6 km) east of Chicago. The park is bounded by Lake Michigan to the northwest and is surrounded by as well as within the authorized boundaries of Indiana Dunes National Park, a unit of the National Park Service; the NPS owns the water from the ordinary high water mark to 300 feet (91 m) offshore. The 1,530-acre (619.2 ha) Dunes Nature Preserve makes up the bulk of eastern part of the park, and includes most of the park's hiking trails and dune landscape. This was one of the first places Richard Lieber considered when establishing the Indiana State Park system. Like all Indiana state parks, there is a fee for entrance. Indiana Dunes State Park was established in 1925 and designated a National Natural Landmark in 1974.
Coastal geography is the study of the constantly changing region between the ocean and the land, incorporating both the physical geography and the human geography of the coast. It includes understanding coastal weathering processes, particularly wave action, sediment movement and weather, and the ways in which humans interact with the coast.
Northwest Indiana, nicknamed The Region after the Calumet Region, comprises Lake, Porter, LaPorte, and Newton counties in Indiana. This region neighbors Lake Michigan and is part of the Chicago metropolitan area. According to the 2020 Census, Northwest Indiana has a population of 831,080 and is the state's second largest urban area after the Indianapolis Metropolitan Area. It is also the home of the Indiana Dunes, parts of which have been preserved through conservation efforts. The town of Ogden Dunes houses the Hour Glass, a museum showcasing the ecological and conservation efforts of O. D. Frank.
Anchor ice is defined by the World Meteorological Organization as "submerged ice attached or anchored to the bottom, irrespective of the nature of its formation". It may also be called bottom-fast ice. Anchor ice is most commonly observed in fast-flowing rivers during periods of extreme cold, at the mouths of rivers flowing into very cold seawater, in the shallow sub or intertidal during or after storms when the air temperature is below the freezing point of the water, and the subtidal in the Antarctic along ice shelves or near floating glacier tongues, and in shallow lakes.
Lake Chicago was a prehistoric proglacial lake that is the ancestor of what is now known as Lake Michigan, one of North America's five Great Lakes. Formed about 13,000 years ago and fed by retreating glaciers, it drained south through the Chicago Outlet River.
An ice dune, also called an ice ridge or an ice foot, is a formation of ice that accumulates on the shores of many arctic beaches and is also common along the shores of the Great Lakes during the winter. Ice dunes are not to be confused with ice shoves, which accumulate on bodies of water then push their way on shore, carrying sediment with them and deforming the shoreline.
The Kankakee Outwash Plain is a flat plain interspersed with sand dunes in the Kankakee River valley in northwestern Indiana and northeastern Illinois of the United States. It is just south of the Valparaiso Moraine and was formed during the Wisconsin Glaciation. As the glacier stopped at the Valparaiso Moraine, its meltwater was carried away to the outwash plain. On the south side of the moraine, where the elevation drops, the meltwaters eroded away valleys, carrying sand and mud with them. As the muddy meltwater reached the valley where the slope lessened, the water slowed, depositing the sand on the outwash plain. This created a smooth, flat, and sandy plain. Before its draining, the Kankakee Marsh, located on the outwash plain, was one of the largest freshwater marshes in the United States.
The Glenwood Shoreline is an ancient shoreline of the precursor to Lake Michigan, Lake Chicago. It is named after the town of Glenwood, Illinois. The shoreline was formed when the lake was higher during the last ice age, while ice blocked the Straits of Mackinac. After the straits were freed, the lake receded and left behind a sand ridge at an elevation of about 640 feet (200 m) where the shore resided. This ridge can be seen clearly in Glenwood, Illinois, Dyer, Indiana, and Schererville, Indiana, all south of Chicago.
The Indiana Dunes comprise ten different habitats. Each provides for a unique combination of plants and animals. The range of the Indiana Dunes varies depending your source. The Indiana Lake Michigan Coastal Program uses the river drainage systems along the shoreline. This expands the area from the areas of lakeshore southward to the edges of the Valparaiso Moraine. This entire region has been dune landscapes since over 114,000 years before present (YBP). Traditionally, the Indiana Dunes area thought of as a narrow area along the shores of Lake Michigan, including the areas of Marquette Park in Gary, Indiana (1920), Indiana Dunes State Park (1926) and Indiana Dunes National Park,. The identified ten habitats can be found in these parks, where they have been preserved, but are also visible throughout the three counties of Northwest Indiana.
A foredune is a dune ridge that runs parallel to the shore of an ocean, lake, bay, or estuary. Foredunes consist of sand deposited by wind on a vegetated part of the shore. Foredunes can be classified generally as incipient or established.
The Toleston Shoreline is the third ancient shoreline of the precursor to Lake Michigan, Lake Chicago. It takes its name from the village of Tolleston, now a portion of Gary, Indiana. The shoreline formed when Lake Chicago was high enough to drain through the Chicago outlet into the Des Plaines River. The beach is 18 to 25 feet above the level of Lake Michigan. The Indiana segment and the Illinois segment, north to Evanston are still visible. North of Evanston and Michigan City, Indiana, the beach has been eroded by later ice movement or shoreline wave action.
Lake Kankakee formed 14,000 years before present (YBP) in the valley of the Kankakee River. It developed from the outwash of the Michigan Lobe, Saginaw Lobe, and the Huron-Erie Lobe of the Wisconsin glaciation. These three ice sheets formed a basin across Northwestern Indiana. It was a time when the glaciers were receding, but had stopped for a thousand years in these locations. The lake drained about 13,000 YBP, until reaching the level of the Momence Ledge. The outcropping of limestone created an artificial base level, holding water throughout the upper basin, creating the Grand Kankakee Marsh.
Lake Wayne formed in the Lake Erie and Lake St. Clair basins around 12,500 years before present (YBP) when Lake Arkona dropped in elevation. About 20 feet (6.1 m) below the Lake Warren beaches it was early described as a lower Lake Warren level. Based on work in Wayne County, near the village of Wayne evidence was found that Lake Wayne succeeded Lake Whittlesey and preceded Lake Warren. From the Saginaw Basin the lake did not discharge water through Grand River but eastward along the edge of the ice sheet to Syracuse, New York, thence into the Mohawk valley. This shift in outlets warranted a separate from Lake Warren. The Wayne beach lies but a short distance inside the limits of the Warren beach. Its character is not greatly different when taken throughout its length in Michigan, Ohio, Pennsylvania and New York. At the type locality in Wayne County, Michigan, it is a sandy ridge, but farther north, and to the east through Ohio it is gravel. The results of the isostatic rebound area similar to the Lake Warren beaches.
Southern Lake Michigan beach in winter at Indiana Dunes National Park
An unbroken stretch of shelf ice at Indiana Dunes National Park
Ridges of shelf ice along Lake Michigan's southern shore at Indiana Dunes National Park
Remnant shelf ice covered with sand and undergoing gradual denivation on a Lake Michigan beach
Shelf ice build up on the Sound North of Copenhagen
