What is Basin (geology)?
[[File:Badwater Basin.jpg|thumb|right|200px|[[Badwater Basin]] in [[Death Valley]], [[California]].]] A [[Geology|geological]] '''basin''' is a large low-lying area. It is often below [[sea level]]. Geological basins are one of the two most common places inland which collect [[sediment]] (the other is [[lake]]s). The type of rocks which form there tell about the palaeo[[climate]] of the [[continent]]. The geology is of interest to [[oil]] prospectors, [[Hydrology|hydrologists]] and [[palaeontologist]]s. == Causes == #One cause is stretching of the [[lithosphere]] ([[Crust (geology)|crust]] + upper [[Mantle (geology)|mantle]]). Examples: [[North Sea]]; [[Nevada]] basin; [[Death Valley]]; [[Red Sea]]. #Overthrusting of a [[continental plate]], at a [[plate boundary]], causes the plate to [[wikt:flex|flex]]. Part goes up, and part goes down. The downward part becomes a ''foreland basin''. Examples: the [[Ebro]] basin next to the [[Pyrenees]] in [[Spain]]; the [[Molasse]] and [[Po River]] basins next to the [[Alps]]. #[[Rift (geology)|Rifting]] can cause basins, as with the [[Dead Sea]] rift. === Death Valley example === [[File:Great Basin definition map.gif|thumb|220px|Full extent of the Basin and Range. (NPS image)]] [[Image:Death Valley basin cross section.png|thumb|right|300px|The deep Death Valley basin is filled with sediment (light yellow) eroded from the surrounding mountains. Black lines show some of the major faults that created the valley. (USGS image)]] Starting around 16 million years ago in the [[Miocene]], and continuing into the present, a large part of the [[North American Plate]] has been stretched by being pulled apart.<ref>Harris, Ann G.; Tuttle, Esther; Tuttle, Sherwood D. 1997. Geology of National Parks. 5th ed, Iowa: Kendall/Hunt Publishing. {{ISBN|0-7872-5353-7}}</ref><sup>p611</sup> The result has been the creation of a large and still-growing region of relatively thin [[Crust (geology)|crust]]; the region grew an average of {{convert|1|in|cm}} per year initially and then slowed to {{conv