Gravel - Wikipedia
Gravel (/ ˈ ɡ r æ v əl /) is a loose aggregation of rock fragments. Gravel occurs naturally on Earth as a result of sedimentary and erosive geological processes; it is also produced in large quantities commercially as crushed stone. Gravel is classified by particle size range and includes size classes from granule- to boulder-sized fragments
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Gravel cycling - Wikipedia
Gravel cycling, gravel biking or gravel grinding [1] is a sport or a leisure activity in which participants ride bicycles, mostly on gravel roads. While often performed on a specially designed gravel bike, any bicycle capable of covering the terrain can be used.. Gravel cycling bridges the gap between road and mountain biking, [2] combining the efficiency of road cycling with the …
Gravel bicycle - Wikipedia
Gravel bikes have frame geometry that is intermediate between a road bike and a cross-country mountain bike, leading to a bike that is slower to turn but more stable, particularly in low-traction descents, than a road bike or cyclocross bike. Gravel bikes almost universally use disc brakes, and many models use hydraulic discs.
Gravel - Simple English Wikipedia, the free encyclopedia
Gravel is small, loose, rock particles. It is any loose rock that is larger than 2 mm (0.079 in) in its smallest dimension (about 1/12 of an inch) and no more than 64 mm (2.5 in). Small gravel is composed of granules (>2 to 4 mm/0.079 to 0.16 in). Large gravel is called pebbles (>4 to 64 mm/0.16 to 2.5 in).
Gravel pit - Wikipedia
Gravel pits are located where there are rich sources of materials suitable to be crushed into aggregate, often at sites of fluvial, glacial, or floodplain geological deposits. [4] Sedimentary and igneous rocks typically produce good quality aggregates of various sizes, but metamorphic rocks are rarely mined at gravel pits as they tend to have ...
Gravel road - Wikipedia
A gravel road is a type of unpaved road surfaced with gravel that has been brought to the site from a quarry or stream bed. Gravel roads are common in less-developed nations, and also in the rural areas of developed nations such as Canada and the United States .
Gravel - New World Encyclopedia
Gravel is rock that is of a certain particle size range. In geology, gravel is any loose rock that is larger than two millimeters (mm) (about 1/12 an inch) in its longest dimension but no more than 63 millimeters (about 2.5 inches). The natural erosion of larger rocks has led to the formation of many gravel deposits.
Gravel (disambiguation) - Wikipedia
Gravel is a type of rock. Gravel or Gravell may also refer to: Gravel (surname) Gravel pit, a mine for gravel; Gravel bar, an accumulation of gravel-size sediment in a river; River gravel, a subtype of gravel stone; Aquarium gravel, the common name for an aquarium's substrate; Gravel road, a type of road; Gravel disease, the archaic name of ...
Gravel History - Gravel Cycling Hall of Fame
Gravel cycling is the original form of cycling. Modern gravel riders are simply rediscovering the sport’s roots. When bicycles first became popular in the mid-19th century, almost all roads worldwide were dirt. Although asphalt roads existed as early as 615 B.C.E in Babylon, they didn’t become common outside of city centers until the 20th ...