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A beach ridge is a wave-swept or wave-deposited ridge running parallel to a shoreline. It is commonly composed of sand as well as sediment worked from underlying beach material. The movement of sediment by wave action is called littoral transport. Movement of material parallel to the shoreline is called longshore transport . Movement perpendicular to the shore is called on-offshore transport. A beach ridge may be capped by, or associated with, sand dunes. The height of a beach ridge is affected by wave size and energy.
A fall in water level (or an uplift of land) can isolate a beach ridge from the body of water that created it. Isolated beach ridges may be found along dry lakes in the western United States and inland of the Great Lakes of North America, where they formed at the end of the last ice age when lake levels were much higher due to glacial melting and obstructed outflow caused by glacial ice. Some isolated beach ridges are found in parts of Scandinavia, where glacial melting relieved pressure on land masses and resulted in subsequent crustal lifting or post-glacial rebound. A rise in water level can submerge beach ridges created at an earlier stage, causing them to erode and become less distinct.
Beach ridges can become routes for roads and trails, like in the case of the west coast in the Netherlands, where isolated beach ridges were formed early on in the Holocene, during the Atlanticum, behind newly formed dunes. Both the old and the new beach ridges are the only dry routes in the middle of wet peatland. Numerous settlements emerged here, some of them developed in large populous centers, like The Hague, Haarlem and Alkmaar.
An esker, eskar, eschar, or os, sometimes called an asar, osar, or serpent kame, is a long, winding ridge of stratified sand and gravel, examples of which occur in glaciated and formerly glaciated regions of Europe and North America. Eskers are frequently several kilometres long and, because of their uniform shape, look like railway embankments.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
Barrier islands are a coastal landform, a type of dune system and sand island, where an area of sand has been formed by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few islands to more than a dozen. They are subject to change during storms and other action, but absorb energy and protect the coastlines and create areas of protected waters where wetlands may flourish. A barrier chain may extend for hundreds of kilometers, with islands periodically separated by tidal inlets. The largest barrier island in the world is Padre Island of Texas, United States, at 113 miles (182 km) long. Sometimes an important inlet may close permanently, transforming an island into a peninsula, thus creating a barrier peninsula, often including a beach, barrier beach. Though many are long and narrow, the length and width of barriers and overall morphology of barrier coasts are related to parameters including tidal range, wave energy, sediment supply, sea-level trends, and basement controls. The amount of vegetation on the barrier has a large impact on the height and evolution of the island.
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.
Glacial Lake Iroquois was a prehistoric proglacial lake that existed at the end of the last ice age approximately 13,000 years ago. The lake was essentially an enlargement of the present Lake Ontario that formed because the St. Lawrence River downstream from the lake was blocked by the ice sheet near the present Thousand Islands. The level of the lake was approximately 30 m (~100 ft) above the present level of Lake Ontario.
Aeolian processes, also spelled eolian, pertain to wind activity in the study of geology and weather and specifically to the wind's ability to shape the surface of the Earth. Winds may erode, transport, and deposit materials and are effective agents in regions with sparse vegetation, a lack of soil moisture and a large supply of unconsolidated sediments. Although water is a much more powerful eroding force than wind, aeolian processes are important in arid environments such as deserts.
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.
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.
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.
Shelf ice is ice that forms when a portion of a lake surface freezes. It is often then washed upon the shore. The phenomenon is common within the Great Lakes.
Cuspate forelands, also known as cuspate barriers or nesses in Britain, are geographical features found on coastlines and lakeshores that are created primarily by longshore drift. Formed by accretion and progradation of sand and shingle, they extend outwards from the shoreline in a triangular shape.
Beach evolution occurs at the shoreline where sea, lake or river water is eroding the land. Beaches exist where sand accumulated from centuries-old, recurrent processes that erode rocky and sedimentary material into sand deposits. River deltas deposit silt from upriver, accreting at the river's outlet to extend lake or ocean shorelines. Catastrophic events such as tsunamis, hurricanes, and storm surges accelerate beach erosion.
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.
Cape Town lies at the south-western corner of the continent of Africa. It is bounded to the south and west by the Atlantic Ocean, and to the north and east by various other municipalities in the Western Cape province of South Africa.
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.
The Kankakee Torrent was a catastrophic flood that occurred about 19,000 calibrated years ago in the Midwestern United States. It resulted from a breach of moraines forming a large glacial lake fed by the melting of the Late Wisconsin Laurentide Ice Sheet. The point of origin of the flood was Lake Chicago. The landscape south of Chicago still shows the effects of the torrent, particularly at Kankakee River State Park and on the Illinois River at Starved Rock State Park.
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.