BASIN, or BASON (the older

See also:

• FORM (Lat. forma)

form bacin is found in many of the Romanic

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• LANGUAGES

languages, from the

See also:

• LATE

Late

See also:

• LAT

Lat. baccinus or bacchinus, probably derived from bacca, a bowl)  , a round vessel for holding liquids . Hence the term has various technical uses, as of a dock constructed with flood-gates in a tidal-river, or of a widening in a canal for unloading barges; also, in physical geography, of the drainage area of a river and its tributaries . In geology, " basin " is equivalent to a broad shallow syncline, i.e. it is a structure proper to the bed rock of the district covered by the term; it must not be confused with the physiographic river basin, although it occasionally happens that the two coincide to some extent . Some of the better known geological basins in England are, the London basin, a shallow trough orsyncline of Tertiary, Cretaceous and Jurassic rocks; the Hampshire basin, of similar formations; and the numerous coal basins, e.g. the S . Wales coalfield, the Forest of Dean, N . Staffordshire coalfield, &c . The Paris basin is made of strata similar to those in the London and Hampshire basins . Strictly speaking, a structural basin is formed of rock beds which exhibit a centroclinal dip; an elongated narrow syncline or trough is not a basin . " Rock-basins " are comparatively small, steep-sided depressions that have been scooped out of the solid rock in mountainous regions, mainly through the agency of glaciers (see CIRQUE) . Lakes sometimes occupy basins that have been caused by the removal in solution of some of the more soluble constituents (rock salt, &c.) in the underlying strata; occasion-ally lake basins have been formed directly by crustal movements .