Glacial period in the context of "Continental shelf"

⭐ In the context of continental shelves, glacial periods are considered to have primarily influenced them through what process?

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⭐ Core Definition: Glacial period

A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age that is marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods. The Last Glacial Period ended about 15,000 years ago. The Holocene is the current interglacial. A time with no glaciers on Earth is considered a greenhouse climate state.

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👉 Glacial period in the context of Continental shelf

A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an island is known as an "insular shelf."

The continental margin, between the continental shelf and the abyssal plain, comprises a steep continental slope, surrounded by the flatter continental rise, in which sediment from the continent above cascades down the slope and accumulates as a pile of sediment at the base of the slope. Extending as far as 500 km (310 mi) from the slope, it consists of thick sediments deposited by turbidity currents from the shelf and slope. The continental rise's gradient is intermediate between the gradients of the slope and the shelf.

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Glacial period in the context of Pleistocene

The Pleistocene (/ˈplstəˌsn, -st-/ PLY-stə-seen, -⁠stoh-; 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. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name comes from Ancient Greek πλεῖστος (pleîstos), meaning "most", and καινός (kainós), meaning "new, recent".

The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold glacial periods and warmer interglacials, with the sea levels being up to 120 metres (390 ft) lower than present at peak glaciation, allowing the periodic connection of Asia and North America via the Beringia land bridge, and the covering of most of northern North America by the large Laurentide Ice Sheet.

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Glacial period in the context of Quaternary glaciation

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 this entire period up to the present as an "ice age", in popular culture this term usually refers to the most recent glacial period, or to the Pleistocene epoch in general. Since Earth still has polar ice sheets, geologists consider the Quaternary glaciation to be ongoing, though currently in an interglacial period.

During the Quaternary glaciation, ice sheets appeared, expanding during glacial periods and contracting during interglacial periods. Since the end of the last glacial period, only the Antarctic and Greenland ice sheets have survived, while other sheets formed during glacial periods, such as the Laurentide Ice Sheet, have completely melted.

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Glacial period in the context of Interglacial

An interglacial period (or alternatively interglacial, interglaciation) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene interglacial began at the end of the Pleistocene, about 11,700 years ago.

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Glacial period in the context of Cape Peninsula

The Cape Peninsula (Afrikaans: Kaapse Skiereiland) of South Africa is a generally mountainous peninsula that juts out into the Atlantic Ocean at the south-western extremity of the African continent. At the southern end of the peninsula are Cape Point and the Cape of Good Hope. On the northern end is Table Mountain, overlooking Table Bay and the City Bowl of Cape Town, South Africa. The peninsula is 52 km long from Mouille point in the north to Cape Point in the south. The Peninsula has been an island on and off for the past 5 million years, as sea levels fell and rose with the ice age and interglacial global warming cycles of, particularly, the Pleistocene. The last time that the Peninsula was an island was about 1.5 million years ago. Soon afterwards it was joined to the mainland by the emergence from the sea of the sandy area now known as the Cape Flats. The towns and villages of the Cape Peninsula and Cape Flats, and the undeveloped land of the rest of the peninsula now form part of the City of Cape Town metropolitan municipality. The Cape Peninsula is bounded to the north by Table Bay, to the west by the open Atlantic Ocean, and to the east by False Bay in the south and the Cape Flats in the north.

The peninsula is mostly the mountainous remnant of very old durable sandstone formations with low dip, deposited unconformably on an ancient underlying granite peneplain. The climate is of the Mediterranean type, with predominantly winter rainfall and mild temperatures, and the natural vegetation is exceptionally diverse, with an unusually large number of endemic plant species for an area of this size, many of which are endangered, and threatened by human activity and encroachment, but are to some extent protected on the large part of the peninsula which is in Table Mountain National Park. The coastal waters include a major seaport in Table Bay, and a marine protected area in the two adjacent but significantly different marine ecoregions, which meet at Cape Point. Most of the lower lying coastal land of the central and northern peninsula has been developed as first agricultural, and later urban areas. The rocky uplands have historically avoided development because of difficult access, poor soils and steep slopes, and more recently have been legally protected as being of high ecological importance, but are threatened by illegal land invasion and informal settlement.

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Glacial period in the context of Epipalaeolithic Near East

The Epipalaeolithic Near East designates the Epipalaeolithic ("Final Old Stone Age") in the prehistory of the Near East. It is the period after the Upper Palaeolithic and before the Neolithic, between approximately 25,000 and 11,500 years Before Present. The people of the Epipalaeolithic were nomadic hunter-gatherers who generally lived in small, seasonal camps rather than permanent villages. They made sophisticated stone tools using microliths—small, finely-produced blades that were hafted in wooden implements. These are the primary artifacts by which archaeologists recognise and classify Epipalaeolithic sites.

Although the appearance of microliths is an arbitrary boundary, the Epipalaeolithic does differ significantly from the preceding Upper Palaeolithic. Epipalaeolithic sites are more numerous, better preserved, and can be accurately radiocarbon dated. The period coincides with the gradual retreat of glacial climatic conditions between the Last Glacial Maximum and the start of the Holocene, and it is characterised by population growth and economic intensification. The Epipalaeolithic ended with the "Neolithic Revolution" and the onset of domestication, food production, and sedentism, although archaeologists now recognise that these trends began in the Epipalaeolithic.

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Glacial period in the context of Doggerland

Doggerland was a large area of land in Northern Europe, now submerged beneath the southern North Sea. This region was repeatedly exposed at various times during the Pleistocene epoch due to the lowering of sea levels during glacial periods. However, the term "Doggerland" is generally specifically used for this region during the Late Pleistocene and Early Holocene. During the early Holocene following the glacial retreat at the end of the Last Glacial Period, the exposed land area of Doggerland stretched across the region between what is now the east coast of Great Britain, northern France, Belgium, the Netherlands, north-western Germany, and the Danish peninsula of Jutland. Between 10,000 and 7,000 years ago, Doggerland was inundated by rising sea levels, disintegrating initially into a series of low-lying islands before submerging completely. The impact of the tsunami generated by the Storegga underwater landslide c. 8,200 years ago on Doggerland is controversial. The flooded land is known as the Dogger Littoral.

Doggerland was named after the present-time Dogger Bank (which in turn was named after 17th-century Dutch fishing boats called doggers), which is the remains of a highland region that became submerged later than the rest of Doggerland.

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