The Younger Dryas was a return to glacial conditions after the Late Glacial Interstadial, which temporarily reversed the gradual climatic warming after the Last Glacial Maximum (LGM) started receding around 20,000 BP. It is named after an indicator genus, the alpine-tundra wildflower Dryas octopetala, as its leaves are occasionally abundant in late glacial, often minerogenic-rich sediments, such as the lake sediments of Scandinavia.
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.
A jökulhlaup is a type of glacial outburst flood. It is an Icelandic term that has been adopted in glaciological terminology in many languages. It originally referred to the well-known subglacial outburst floods from Vatnajökull, Iceland, which are triggered by geothermal heating and occasionally by a volcanic subglacial eruption, but it is now used to describe any large and abrupt release of water from a subglacial or proglacial lake/reservoir.
An outwash plain, also called a sandur, sandr or sandar, is a plain formed of glacial sediments deposited by meltwater outwash at the terminus of a glacier. As it flows, the glacier grinds the underlying rock surface and carries the debris along. The meltwater at the snout of the glacier deposits its load of sediment over the outwash plain, with larger boulders being deposited near the terminal moraine, and smaller particles travelling further before being deposited. Sandurs are common in Iceland where geothermal activity accelerates the melting of ice flows and the deposition of sediment by meltwater.
The Howgill Fells are hills in Northern England between the Lake District and the Yorkshire Dales, lying roughly in between the vertices of a triangle made by the towns of Sedbergh, Kirkby Stephen and Tebay. The name Howgill derives from the Old Norse word haugr meaning a hill or barrow, plus gil meaning a narrow valley.
The Oak Ridges Moraine is a geological landform that runs east-west across south central Ontario, Canada. It developed about 12,000 years ago, during the Wisconsin glaciation in North America. A complex ridge of sedimentary material, the moraine is known to have partially developed under water. The Niagara Escarpment played a key role in forming the moraine in that it acted as a dam for glacial meltwater trapped between it and two ice lobes.
In geology, a terrace is a step-like landform. A terrace consists of a flat or gently sloping geomorphic surface, called a tread, that is typically bounded on one side by a steeper ascending slope, which is called a "riser" or "scarp". The tread and the steeper descending slope together constitute the terrace. Terraces can also consist of a tread bounded on all sides by a descending riser or scarp. A narrow terrace is often called a bench.
A tunnel valley is a U-shaped valley originally cut under the glacial ice near the margin of continental ice sheets such as that now covering Antarctica and formerly covering portions of all continents during past glacial ages. They can be as long as 100 km (62 mi), 4 km (2.5 mi) wide, and 400 m (1,300 ft) deep.
Lake Pickering was an extensive proglacial lake of the Devensian glacial. It filled the Vale of Pickering between the North York Moors and the Yorkshire Wolds, when the ice blocked the drainage, which had flowed north-eastwards past the site of Filey towards the Northern North Sea basin. The lake surface rose until it overflowed southwards and cut an exit between the Howardian Hills and the Yorkshire Wolds at Kirkham Priory between Malton and Stamford Bridge, so creating the River Derwent.
Glacial River Warren, also known as River Warren, was a prehistoric river that drained Lake Agassiz in central North America between about 13,500 and 10,650 BP calibrated years ago. A part of the uppermost portion of the river channel was designated a National Natural Landmark in 1966.
The Geology of Yorkshire in northern England shows a very close relationship between the major topographical areas and the geological period in which their rocks were formed. The rocks of the Pennine chain of hills in the west are of Carboniferous origin whilst those of the central vale are Permo-Triassic. The North York Moors in the north-east of the county are Jurassic in age while the Yorkshire Wolds to the south east are Cretaceous chalk uplands. The plain of Holderness and the Humberhead levels both owe their present form to the Quaternary ice ages. The strata become gradually younger from west to east.
Chisworth is a hamlet near Glossop, Derbyshire, England. It is 3 miles (4.8 km) south-west of Glossop town centre, on the south side of the Etherow valley. The parish of Chisworth was formed in 1896, out of the parish of Chisworth and Ludworth. In 1901, it had a population of 409. From 1896 until 1934 it was in the Glossop Rural District, when it was placed with Ludworth into the Chapel en le Frith Rural District. The village possesses a Methodist chapel. The A626 road passed through the hamlet. In June 1930, a local cloudburst caused flooding that killed one man and destroyed equipment at the mills, one of which never reopened.
Lake Great Falls was a prehistoric proglacial lake which existed in what is now central Montana in the United States between 15,000 BCE and 11,000 BCE. Centered on the modern city of Great Falls, Montana, Glacial Lake Great Falls extended as far north as Cut Bank, Montana, and as far south as Holter Lake. At present-day Great Falls, the Glacial Lake Great Falls reached a depth of 600 feet.
An urstromtal is a type of broad glacial valley, for example, in northern Central Europe, that appeared during the ice ages, or individual glacial periods of an ice age, at the edge of the Scandinavian ice sheet and was formed by meltwaters that flowed more or less parallel to the ice margin. Urstromtäler are an element of the glacial series. The term is German and means "ancient stream valley". Although often translated as "glacial valley", it should not be confused with a valley carved out by a glacier. More accurately some sources call them "meltwater valleys" or "ice-marginal valleys".
The Shonkin Sag is a prehistoric fluvioglacial landform located along the northern edge of the Highwood Mountains in the state of Montana in the United States. The Sag is a river channel formed by the Missouri River and glacial meltwater pouring from Glacial Lake Great Falls. It is one of the most famous prehistoric meltwater channels in the world.
New England is a region in the North Eastern United States consisting of the states Rhode Island, Connecticut, Massachusetts, New Hampshire, Vermont, and Maine. Most of New England consists geologically of volcanic island arcs that accreted onto the eastern edge of the Laurentian Craton in prehistoric times. Much of the bedrock found in New England is heavily metamorphosed due to the numerous mountain building events that occurred in the region. These events culminated in the formation of Pangaea; the coastline as it exists today was created by rifting during the Jurassic and Cretaceous periods. The most recent rock layers are glacial conglomerates.
Glacial Lake Glendive was a glacial lake on the lower Yellowstone River. It formed in the valley of Yellowstone, during the late Pleistocene epoch south of the Keewatin Ice Sheet. As the ice sheet retreated northward, the lake drained into the modern Missouri River.
A meltwater channel is a channel cut into ice, bedrock or unconsolidated deposits by the flow of water derived from the melting of a glacier or ice-sheet. The channel may form on the surface of, within, beneath, along the margins of or downstream from the ice mass. Accordingly it would be referred to as supraglacial, englacial, subglacial, lateral or proglacial.
