gravel

gravel
gravelish, adj.
/grav"euhl/, n., v., graveled, graveling or (esp. Brit.) gravelled, gravelling, adj.
n.
1. small stones and pebbles, or a mixture of these with sand.
2. Pathol.
a. multiple small calculi formed in the kidneys.
b. the disease characterized by such concretions.
v.t.
3. to cover with gravel.
4. to bring to a standstill from perplexity; puzzle.
5. Informal. to be a cause of irritation to.
6. Obs. to run (a ship) aground, as on a beach.
adj.
7. harsh and grating: a gravel voice.
[1250-1300; ME < OF gravele, dim. of grave sandy shore, perh. < Celt; cf. GRAVE4, GROWAN]

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Aggregate of more or less rounded rock fragments coarser than sand (i.e., more than 0.08 in., or 2 mm, in diameter).

Gravel beds in some places contain heavy metallic ore minerals, such as cassiterite (a major source of tin), or native metals, such as gold, in nuggets or flakes. Deposits accumulate in parts of stream channels or on beaches where the water moves too rapidly to permit sand to remain. Because of changing conditions, gravel formations generally are more limited and more variable in coarseness, thickness, and configuration than sand or clay deposits. In many regions gravel terraces (or raised beaches) extend great distances inland, indicating that the sea at one time stood higher than it does today. Gravels are widely used building materials.

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      aggregate of more or less rounded rock fragments coarser than sand (i.e., more than 2 mm [0.08 inch] in diameter). Gravel beds in some places contain accumulations of heavy metallic ore minerals, such as cassiterite (a major source of tin), or native metals, such as gold, in nuggets or flakes. Gravels are widely used building materials.

      Fragments in gravel range in size from pebbles (4–64 mm [0.16–2.52 inches] in diameter), through cobbles (64–256 mm [2.52–10.08 inches]), to boulders (larger than 256 mm). The rounding of gravel results from abrasion in the course of transport by streams or from milling by the sea. Gravel deposits accumulate in parts of stream channels or on beaches where the water moves too rapidly to permit sand to remain. Because of changing conditions, gravel formations generally are more limited and more variable in coarseness, thickness, and configuration than sand or clay deposits. Persistent accumulation of gravel or pebble beds may take place along an inner zone of breaking waves, on a beach that is otherwise sandy. Cobble and pebble beaches (shingle beaches) often originate from the points of rocky cliffs.

      In many regions marine gravels similar to those of the seashore exist tens or hundreds of metres above tide level; such gravel terraces (or raised beaches) may extend great distances and indicate that the sea at one time stood relatively higher. River gravels occur mostly in the middle and upper parts of streams where the currents are swiftest. Ancient gravel terraces found at levels much above those of the present rivers mark former streams or are evidence of uplift of the land or lowering of the sea.

      The prolonged weathering and extended transport of gravel by long rivers results in more complete rounding and sorting of the rock fragments by size and physical and chemical durability. Cemented gravels are called conglomerates.

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Universalium. 2010.

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  • Gravel — Grav el, v. t. [imp. & p. p. {Graveled}or {Gravelled}; p. pr. & vb. n. {Graveling} or {Gravelling}.] [1913 Webster] 1. To cover with gravel; as, to gravel a walk. [1913 Webster] 2. To run (as a ship) upon the gravel or beach; to run aground; to… …   The Collaborative International Dictionary of English

  • Gravel — ist der Familienname von: Camille Gravel (1915–2005), US amerikanischer Politiker Mike Gravel, US amerikanischer Politiker Raymond Gravel, kanadischer Politiker und katholischer Priester Robert de Gravel (1616–1684), französischer Diplomat unter… …   Deutsch Wikipedia

  • Gravel — Grav el, n. [OF. gravele, akin to F. gr?ve a sandy shore, strand; of Celtic origin; cf. Armor. grouan gravel, W. gro coarse gravel, pebbles, and Skr. gr[=a]van stone.] 1. Small stones, or fragments of stone; very small pebbles, often intermixed… …   The Collaborative International Dictionary of English

  • gravel — (n.) early 13c., from O.Fr. gravele sand, gravel, dim. of grave sand, seashore (Mod.Fr. grève), possibly from Celtic *gravo (Cf. Welsh gro coarse gravel, Bret. grouan, Cornish grow gravel ), perhaps ultimately from PIE *ghreu to rub, grind …   Etymology dictionary

  • gravel — ► NOUN ▪ a loose mixture of small stones and coarse sand, used for paths and roads. ► VERB (gravelled, gravelling; US graveled, graveling) ▪ cover with gravel. ORIGIN Old French, from grave shore …   English terms dictionary

  • gravel — [grav′əl] n. [ME < OFr gravelle, dim. of grave, coarse sand, seashore < or akin to Gaul * grava, stone < IE base * ghreu , to rub hard, pulverize > GRIT] 1. a loose mixture of pebbles and rock fragments coarser than sand, often mixed… …   English World dictionary

  • Gravel — Toponyme désignant un lieu gravillonneux ou caillouteux, le nom est notamment porté dans l Orne et dans l Oise. Avec le même sens : Graveau, Graveaud (17), Gravelle (59, 25) …   Noms de famille

  • Gravel — For other uses, see Gravel (disambiguation). Gravel (largest fragment in this photo is about 4 cm) …   Wikipedia

  • Gravel —  Pour l’article homophone, voir Gravelle.  Cette page d’homonymie répertorie des personnes (réelles ou fictives) partageant un même patronyme. Gravel est un patronyme fréquent au Québec. La plupart de ceux qui le portent descendent de… …   Wikipédia en Français

  • gravel — I. noun Etymology: Middle English, from Anglo French gravele, diminutive of grave, greve river bank, stony ground Date: 13th century 1. obsolete sand 2. a. loose rounded fragments of rock b. a stratum or deposit of gravel; also a surface covered… …   New Collegiate Dictionary

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