Precambrian age

См. также в других словарях:

• Precambrian time — Interval of geologic time from с 3. 8 billion years ago, the age of the oldest known rocks, to 544 million years ago, the beginning of the Cambrian Period. This interval represents more than 80% of the geologic record and thus provides important… …   Universalium

• Precambrian — For the album by German band The Ocean, see Precambrian (album). Precambrian Period 4567.17–542 million years ago …   Wikipedia

• Age of the Earth — This article is about scientific estimates of the age of the Earth. For religious and other non scientific estimates, see Dating Creation. Earth as seen from Apollo 17 The age of the Earth is 4.54 billion years (4.54 × 109 years ± 1%) …   Wikipedia

• Ice age — An ice age is a period of long term reduction in the temperature of the Earth s surface and atmosphere, resulting in an expansion of continental ice sheets, polar ice sheets and alpine glaciers. Glaciologically, ice age is often used to mean a… …   Wikipedia

• ice age — Geol. (often caps.) the glacial epoch, esp. the Pleistocene Epoch. [1870 75] * * * or glacial age Any geologic period during which thick ice sheets cover vast areas of land. Such periods of large scale glaciation may last several million years… …   Universalium

• ice age — ice′ age n. 1) gel (often caps.) the geologically recent Pleistocene Epoch, during which much of the Northern Hemisphere was covered by great ice sheets 2) gel any one of the Permian, Carboniferous, Cambrian, or Precambrian glaciations •… …   From formal English to slang

• sedimentary rock — Rock formed at or near the Earth s surface by the accumulation and lithification of fragments of preexisting rocks or by precipitation from solution at normal surface temperatures. Sedimentary rocks can be formed only where sediments are… …   Universalium

• continental shield — Any of the large stable areas of low relief (little variation in elevations) in the Earth s crust that are composed of Precambrian crystalline rocks. These rocks are always more than 570 million years old, and some are as old as 2–3 billion years …   Universalium

• hydrosphere — /huy dreuh sfear /, n. the water on or surrounding the surface of the globe, including the water of the oceans and the water in the atmosphere. [1885 90; HYDRO 1 + SPHERE] * * * Discontinuous layer of water at or near the Earth s surface. It… …   Universalium

• Moine Supergroup — Map of the distribution of the Moine Supergroup on Mainland Scotland and the Inner Hebrides The Moine Supergroup is a sequence of Neoproterozoic metamorphic rocks that form the dominant outcrop of the Scottish Highlands between the Moine Thrust… …   Wikipedia

• mountain — mountainless, adj. /mown tn/, n. 1. a natural elevation of the earth s surface rising more or less abruptly to a summit, and attaining an altitude greater than that of a hill, usually greater than 2000 ft. (610 m). 2. a large mass of something… …   Universalium