4,992
edits
Line 16: | Line 16: | ||
== Geography oddities == | == Geography oddities == | ||
=== | === Sinkholes === | ||
* sinkholes are holes or caves in the ground caused by erosion or a collapse of a lower, below-ground surface, usually because of water drainage | |||
* sinkholes may also be caused by a drainage of water, such as a water table decline | |||
* sinkholes are most common where limestone, sandstone, salt beds, or gypsum are prevalent | |||
[[File:Thor's Well (37588682016).jpg|450px|border|right|thumb|Thor's Well: a sinkhole on the coast of Cape Perpetua, Oregon]] | [[File:Thor's Well (37588682016).jpg|450px|border|right|thumb|Thor's Well: a sinkhole on the coast of Cape Perpetua, Oregon]] | ||
* Thor's Well: a sinkhole on the coast of Cape Perpetua, Oregon, that drains at high tides | * Thor's Well: a sinkhole on the coast of Cape Perpetua, Oregon, that drains at high tides | ||
[[File:December_Giant_sinkhole_collapse_USGS_1972.jpg|400px|border||right|thumb|More than three acres of forest suddenly disappeared into this "December Giant" sinkhole in Montevallo, Alabama, USA.]] | |||
* See | |||
** [[https://en.wikipedia.org/wiki/Sinkhole Sinkhole (wiki)]] | |||
=== Enclaves & Exclaves === | === Enclaves & Exclaves === |