TillTill, or glacial till, is unsortedglacialsediment. Till is derived from the erosion and entrainment of material by the moving ice of a glacier. It is deposited some distance down-ice to form terminal, lateral, medial and ground moraines. Till is classified into primary deposits, laid down directly by glaciers, and secondary deposits, reworked by fluvial transport and other processes.
MoraineA moraine is any accumulation of unconsolidated debris (regolith and rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions and that has been previously carried along by a glacier or ice sheet.
Wisconsin glaciationThe Wisconsin glaciation, also called the Wisconsin glacial episode, was the most recent glacial period of the North American ice sheet complex, peaking more than 20,000 years ago.
Laurentide ice sheetThe Laurentide ice sheet (LIS) was a massive sheet of ice that covered millions of square miles, including most of Canada and a large portion of the Northern United States, multiple times during the Quaternary glaciation epochs, from 2.58 million years ago to the present.
Midwestern United StatesCensus region of the United StatesRegion in the United StatesThe Midwestern United States (also referred to as the Midwest, the Heartland, the American Midwest, Middle America, or the Middle West) is one of the four census regions defined by the United States Census Bureau. It occupies the northern central part of the United States. It was officially named the North Central Region by the U.S. Census Bureau until 1984.
GlacierPersistent body of ice that moves downhill under its own weightGlacier of the Geikie Plateau in GreenlandThe Taschachferner in the Ötztal Alps in Austria. The mountain to the left is the Wildspitze (3,768 m), the second highest in AustriaThe Baltoro Glacier in Pakistan. It is 62 kilometres (39 mi) long, the fifth longest alpine glacier in the world.A glacier (US: ; UK: or ) is a persistent body of natural ice, a form of rock, that is constantly moving under its own weight.
SedimentIn Earth and planetary sciences, sediment is a solid material made of loose particles that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles.
PleistoceneFirst epoch of the Quaternary PeriodSubdivision of the Quaternary according to the ICS, as of 2024.Vertical axis scale: Millions of years agoEtymologyName formalityFormalUsage informationCelestial bodyEarthRegional usageGlobal (ICS)DefinitionChronological unitEpochStratigraphic unitSeriesTime span formalityFormalLower boundary definitionBase of magnetic polarity chronozone C2r (Matuyama).Extinction of the haptophytesDiscoaster pentaradiatus and Discoaster surculusLower boundary GSSPMonte San Nicola Section, Gela, Sicily, Italy37°08′49″N14°12′13″E / 37.1469°N 14.2035°E / 37.1469; 14.2035Lower GSSP ratified2009 (as base of Quaternary and Pleistocene)Upper boundary definitionEnd of the Younger DryasstadialUpper boundary GSSPNGRIP2 ice core, Greenland75°06′00″N42°19′12″W / 75.1000°N 42.3200°W / 75.1000; -42.3200Upper GSSP ratified2008 (as base of Holocene)The Pleistocene ( ; referred to colloquially as the Ice Age) is the geological epoch that lasted from c. 2.58 million to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations.
PlainIn geography, a plain, commonly known as flatland, is a flat expanse of land that generally has few rapid or steep changes in elevation. Natural vegetation in plains can include prairies/grasslands, forests, savanah, tundra, and desert biomes, among others. Plains occur as lowlands along valleys or at the base of mountains, as coastal plains, and as plateaus or uplands.
IceFrozen water; the solid state of waterIce is water that is frozen into a solid state, typically forming at or below temperatures of 0 °C, 32 °F, or 273.15 K. It occurs naturally on Earth, on other planets, in Oort cloud objects, and as interstellar ice. As a naturally occurring crystalline inorganic solid with an ordered structure, ice is considered to be a mineral.
North DakotaU.S. stateState in the United StatesNorth Dakota ( ) is a landlocked U.S. state in the Upper Midwest, named after the indigenous Dakota and Sioux peoples. It is bordered by the Canadian provinces of Saskatchewan and Manitoba to the north and by the U.S. states of Minnesota to the east, South Dakota to the south, and Montana to the west. North Dakota is part of the Great Plains region, characterized by broad prairies, steppe, temperate savanna, badlands, and farmland.
HoloceneCurrent geological epochSubdivision of the Holocene according to the ICS, as of 2024.Vertical axis scale: Gregorian yearsEtymologyName formalityFormalUsage informationCelestial bodyEarthRegional usageGlobal (ICS)Time scale(s) usedICS Time ScaleDefinitionChronological unitEpochStratigraphic unitSeriesTime span formalityFormalLower boundary definitionEnd of the Younger Dryasstadial.Lower boundary GSSPNGRIP2 ice core, Greenland75°06′00″N42°19′12″W / 75.1000°N 42.3200°W / 75.1000; -42.3200Lower GSSP ratified2008Upper boundary definitionPresent dayUpper boundary GSSPN/AN/AUpper GSSP ratifiedN/AThe Holocene () is the current geological epoch, beginning approximately 11,700 years ago.*As an Amazon Associate I earn from qualifying purchases.