A push moraine or pushed moraine is in

geomorphology Geomorphology () is the scientific study of the origin and evolution of topographic and bathymetric features generated by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand wh ...

moraine A moraine is any accumulation of unconsolidated debris (regolith and Rock (geology), 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 gla ...

landform A landform is a land feature on the solid surface of the Earth or other planetary body. They may be natural or may be anthropogenic (caused or influenced by human activity). Landforms together make up a given terrain, and their arrangement ...

formed by

glacial A glacier (; or ) is a persistent body of dense ice, a form of rock, that is constantly moving downhill under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires ...

processes) that forms when the terminus advance of a lowland glacier pushes unstratified glacial sediment into a pile or linear ridge in front of it. A push moraine is identified by its ability to push sediment upwards from its original horizontal position. Push moraines are limited in size by the advance of a glacier front and its tendency to shear over the top of any ridge large enough to resist the movement of ice. Pushed moraines generally occur in low, flat plains at higher

latitude In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...

s and were formed during the glacial stages of the

Quaternary ice age The Quaternary glaciation, also known as the Pleistocene glaciation, is an alternating series of glacial and interglacial periods during the Quaternary period that began 2.58 Ma (million years ago) and is ongoing. Although geologists describe ...

. They can be up to 100 km long and several hundreds of metres in height. Pushed moraines can be found in the North American plains, in

Siberia Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states ...

and in Northern Europe. They were formed during cool, glacial stages, when glaciers advanced and covered large parts of North America and Eurasia. In some regions pushed moraines of more than one glacial stage can be recognised, or different generations from a single glacial phase. Since new glacial advances tend to destroy older pushed moraines, most were formed during the last (110,000 to 10,000 years ago) or second-last (238,000 to 128,000 years ago) glacial advances. Today push moraines can be found anywhere an advancing glacier is pushing sediment into a ridge at the terminus. The largest push moraine in the world is

the Dirt Hills The Dirt Hills and neighbouring Cactus Hills, are an arcuate moraine and the largest Push moraine, glacial push in the world. The hills were formed during the deglaciation of the Last Glacial Period, last ice age over 10,000 years ago. They ar ...

in southern

Saskatchewan Saskatchewan is a Provinces and territories of Canada, province in Western Canada. It is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and to the south by the ...

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

. The hills are located about 60 kilometres south-east of city of

Moose Jaw Moose Jaw is the List of cities in Saskatchewan, fourth largest city in Saskatchewan, Canada. Lying on the Moose Jaw River in the south-central part of the province, it is situated on the Trans-Canada Highway, west of Regina, Saskatchewan, Re ...

, along the

Missouri Coteau The Missouri Coteau, or Missouri Plateau, () is a large plateau that stretches along the eastern side of the valley of the Missouri River in central North Dakota and north-central South Dakota in the United States. In the Canadian provinces of Sa ...

References

Moraines Glaciology {{glaciology-stub

See also

References