Golden future network

Geology (from Greek: ??, gê, "earth"; and ?????, logos, "speech" lit. to talk about the earth) is the science and study of the solid and liquid matter that constitutes the Earth. The field of geology encompasses the study of the composition, structure, physical properties, dynamics, and history of Earth materials, and the processes by which they are formed, moved, and changed. The field is a major academic discipline, and is also important for mineral and hydrocarbon extraction, knowledge about and mitigation of natural hazards, some engineering fields, and understanding past climates and environments.

Category: File - :2007-06-18 - Gare de Paris-Est - TGV 4402.JPG|thumb|right|World speed record holding (574.8 km/h/357mph) TGV ? the V150.

Category: File - :Class 395 Javelin STP 001.jpg|thumb|British Rail Class 395 high-speed train at St Pancras International

High-speed rail is a type of passenger rail transport that operates significantly faster than the normal speed of rail traffic. Specific definitions include 200 km/h (125 mph) and faster ? depending on whether the track is upgraded or new ? by the European Union, and above 90 mph (145 km/h) by the United States Federal Railroad Administration, but there is no single standard, and lower speeds can be required by local constraints.

While high-speed rail is usually designed for passenger travel, some high-speed systems also carry some kind of freight service. For instance, the French mail service La Poste owns a few special TGV trains for carrying postal freight.

An equatorial bulge is a bulge which a planet may have around its equator, distorting it into an oblate spheroid. The Earth has an equatorial bulge of 42.72 km (26.5 miles) due to its rotation: its diameter measured across the equatorial plane (12756.28 km, 7,927 miles) is 42.72 km more than that measured between the poles (12713.56 km, 7,900 miles).

An often-cited result of Earth's equatorial bulge is that the highest point on Earth, measured from the center outwards, is the peak of Mount Chimborazo in Ecuador, rather than Mount Everest. But since the ocean, like the Earth and the atmosphere, bulges, Chimborazo is not as high above sea level as Everest is.