Editing Flysch (section)

==Tectonics==

In a [[continental collision]], a [[subduction|subducting]] tectonic plate pushes on the plate above it, making the rock [[fold (geology)|fold]], often to the point where [[thrust fault]]s form, and a mountain chain rises. On the upper plate, the land between the mountains and the undeformed continent bends downward, forming a [[foreland basin]]. If the basin forms slowly, as in the northern [[Appalachian Mountains|Appalachians]], it fills with shallow-water sediments.<ref name=Twiss>{{cite book| last1 = Moores | first1 = Eldridge M. |last2=Twiss|first2=Robert J. |title=Tectonics|date=2000|publisher=Freeman|location=New York|isbn=0716724375|pages=265&ndash;266|edition=3rd print}}</ref> If it forms rapidly, as in the east side of the [[North American Cordillera]], then sea water may rush in, and the first sedimentary deposits are deep water deposits. If the mountain slope is steep enough at the edge of the basin, it will shed material in rapidly moving sedimentary flows called [[turbidity current]]s, resulting in [[turbidite]] deposits. As the basin fills up, shallow-water sandstones and continental deposits form.<ref name=Twiss/><ref name=Einsele>{{cite book|last1=Einsele|first1=Gerhard|title=Sedimentary Basins : Evolution, Facies, and Sediment Budget|url=https://archive.org/details/sedimentarybasin00eins|url-access=limited|date=2000|publisher=Springer|location=Berlin|isbn=9783540661931|edition=2nd|pages=[https://archive.org/details/sedimentarybasin00eins/page/n217 210]&ndash;211}}</ref> Most of the resulting rocks have little deformation, but near the edge of the mountain chain they can be subject to folding and thrusting.<ref name=Twiss/> After the basin fills up, continental sediments ([[molasse]]) are deposited on top of the flysch.<ref name=Einsele/>