Kettle (landform)

A kettle (kettle hole, pothole) is a shallow, sediment-filled body of water formed by retreating glaciers or draining floodwaters. The kettles are formed as a result of blocks of ice calving from glaciers and becoming submerged in the sediment on the outwash plain. Another source is the sudden drainage of an ice-dammed lake. When the block melts, the hole it leaves behind is a kettle. As the ice melts, ramparts can form around the edge of the kettle hole. The lakes that fill these holes are seldom more than 10 m (33 ft) and eventually become filled with sediment. In acid conditions, a kettle bog may form but in alkaline conditions, it will be kettle peatland.

Overview

Kettles are fluvioglacial landforms occurring as the result of blocks of ice calving from the front of a receding glacier and becoming partially to wholly buried by glacial outwash. Glacial outwash is generated when streams of meltwater flow away from the glacier and deposit sediment to form broad outwash plains called sandurs. When the ice blocks melt, kettle holes are left in the sandur. When the development of numerous kettle holes disrupt sandur surfaces, a jumbled array of ridges and mounds form, resembling kame and kettle topography. Kettle holes can also occur in ridge shaped deposits of loose rock fragments called till.

Kettle

A kettle, sometimes called a tea kettle or teakettle, is a type of pot, typically metal, specialized for boiling water, with a lid, spout and handle, or a small kitchen appliance of similar shape that functions in a self-contained manner. Kettles can be heated either by placing on a stove, or by their own internal electric heating element in the appliance versions.

History

The first kettles were used in ancient Mesopotamia for purposes other than cooking. Over time these artistically decorated earthenware containers became more frequently utilized in the kitchen. In China, kettles were typically made of iron and were placed directly over an open flame. Travellers used the kettles to boil fresh water to make it suitable for drinking.

The word kettle originates from Old Norse ketill "cauldron". The Old English spelling was cetel with initial che- [t?] like 'cherry', Middle English (and dialectal) was chetel, both come (together with German Kessel "cauldron") ultimately from Germanic *katilaz, that was borrowed from Latin catillus, diminutive form of catinus "deep vessel for serving or cooking food", which in various contexts is translated as "bowl", "deep dish", or "funnel".

Kettle (birds)

A kettle is a term that birders use to describe a group of birds wheeling and circling in the air. The kettle may be composed of several different species at the same time. Nature photographer M. Timothy O'Keefe theorizes that the word derives from the appearance of birds circling tightly in a thermal updraft "like something boiling in a cauldron." Ornithologist Donald Heintzelman has done more than anyone to popularize the term kettle, using the term at least as early as 1970 in his book Hawks of New Jersey to describe raptor flight, followed by uses in print over four decades. The related terms "caldron" and "boil" are also heard to describe the same sorts of raptor behavior. Osprey-watcher David Gessner, however, claims a Pennsylvania lowland called the Kettle ("der Kessel" in Pennsylvania Dutch), near Hawk Mountain, is the source of the term.

In some species—e.g., the terns of Nantucket—kettling behavior is evidently a way of "staging" a flock in readiness for migration. Pre-migrational turkey vultures kettle by the hundreds in the thermals that rise over Vancouver Island before they venture across the Strait of Juan de Fuca toward Washington State. At Hawk Mountain, broad-winged hawks form kettles in September before flying south. Kettling apparently serves as a form of avian communication—an announcement of imminent departure—as well as a way of gaining altitude and conserving strength.

Kettle (disambiguation)

A kettle is a vessel for heating water. Kettle may also refer to:

Places

Fiction

Other uses

Geology

Geology (from the Greek γῆ, gē, i.e. "earth" and -λoγία, -logia, i.e. "study of, discourse") is an earth science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which they change. Geology can also refer generally to the study of the solid features of any celestial body (such as the geology of the Moon or Mars).

Geology gives insight into the history of the Earth by providing the primary evidence for plate tectonics, the evolutionary history of life, and past climates. Geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, and for providing insights into past climate change. Geology also plays a role in geotechnical engineering and is a major academic discipline.

Geologic materials

The majority of geological data comes from research on solid Earth materials. These typically fall into one of two categories: rock and unconsolidated material.

Country rock (geology)

Country rock is a geological term meaning the rock native to an area. It is similar and in many cases interchangeable with the terms basement and wall rocks.

The term is used to denote the usual strata of a region in relation to the rock which is being discussed or observed.

The following are areas in geology when the term country rock is used;

Geology (journal)

Geology is a publication of the Geological Society of America (GSA). The GSA claims that it is the most widely read scientific journal in the field of earth science. It is published monthly, with each issue containing 20 or more articles, and an annual total of 1166 pages.

One of the goals of the journal is to provide a forum for shorter articles and less focus on pure academic research type articles.

See also

References

External links