|
A foreland basin is a structural basin that develops adjacent and parallel to a mountain belt. Foreland basins form because the immense mass created by crustal thickening associated with the evolution of a mountain belt causes the lithosphere to bend, by a process known as lithospheric flexure. The width and depth of the foreland basin is determined by the flexural rigidity of the underlying lithosphere, and the characteristics of the mountain belt. The foreland basin receives sediment that is eroded off the adjacent mountain belt, filling with thick sedimentary successions that thin away from the mountain belt. Foreland basins represent an endmember basin type, the other being rift basins. Space for sediments, accommodation space, is provided by loading and downflexure to form foreland basins, in contrast to rift basins, where accommodation space is generated by lithospheric extension. ==Types of foreland basin== Foreland basins can be divided into two categories: * Peripheral (Pro) foreland basins, which occur on the plate that is subducted or underthrust during plate collision (i.e. the outer arc of the orogen) * * Examples include the North Alpine Foreland Basin of Europe, or the Ganges Basin of Asia * Retroarc (Retro) foreland basins, which occur on the plate that overrides during plate convergence or collision (i.e. situated behind the magmatic arc that is linked with the subduction of oceanic lithosphere) * * Examples include the Andean basins, or Late Mesozoic to Cenozoic Rocky Mountain Basins of North America 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「foreland basin」の詳細全文を読む スポンサード リンク
|