phreatic water

См. также в других словарях:

• phreatic water —    That part of the underground water in a karst limestone which lies within the zone of permanently saturated rock the phreatic zone. Caves formed within this zone are known as phreatic caves [19].    See phreas …   Lexicon of Cave and Karst Terminology

• phreatic surface — water table (top of the zone of saturation) …   Dictionary of ichthyology

• Phreatic — The term phreatic is used in Earth sciences to refer to matters relating to ground water below the static water table (the word originates from the Greek phrear , phreat meaning well or spring ). The term phreatic surface is where the hydrostatic …   Wikipedia

• phreatic cave —    1. Cave conceived and developed by dissolution, usually below the water table, where all voids are water filled within the phreas. Phreatic caves may include loops deep below the water table, particularly in dipping limestone with widely… …   Lexicon of Cave and Karst Terminology

• Phreatic eruption — A Phreatic eruption, also called an ultravulcanian eruption, occurs when rising magma makes contact with ground or surface water. The extreme temperature of the magma (anywhere from 600 °C to 1,170 °C (1110–2140 °F)) causes near instantaneous… …   Wikipedia

• phreatic eruption — ALASKA VOLCANO OBSERVATORY GLOSSARY An explosive volcanic eruption caused when water and heated volcanic rocks interact to produce a violent expulsion of steam and pulverized rocks. Magma is not involved. GLOSSARY OF VOLCANIC TERMS A steam… …   Glossary of volcanic terms

• ground water —    , phreatic water    1. The part of the subsurface water that is in the phreatic zone [10].    Its lower limits are the zone of rock flowage or the lowest fully confining bed; its upper limits are the uppermost fully confining bed or the water… …   Lexicon of Cave and Karst Terminology

• Water table — The water table is the level at which the ground water pressure is equal to atmospheric pressure. It may be conveniently visualized as the surface of the ground water in a given vicinity. It usually coincides with the phreatic surface , but can… …   Wikipedia

• Phreatic zone — The phreatic zone (from Ancient Greek phrear, phreat a well ), or zone of saturation, is the area in an aquifer, below the water table, in which relatively all pores and fractures are saturated with water. The phreatic zone may fluctuate with… …   Wikipedia

• water-table cave —    In theory the water table offers the prime environment for cave development as it provides the shortest route through the phreas and is potentially more active chemically due to the presence of the air/water interface. However, geological… …   Lexicon of Cave and Karst Terminology

• phreatic zone —    1. Those parts of the earth’s crust in which all voids are filled with water under pressure greater than atmospheric [22].    2. That part of the earth’s crust beneath the regional water table in which all voids, large and small, are ideally… …   Lexicon of Cave and Karst Terminology