Hurricane Harvey Warning: You are not logged in. Your IP address will be publicly visible if you make any edits. If you log in or create an account, your edits will be attributed to your username, along with other benefits.Anti-spam check. Do not fill this in! ===Subsidence=== As Houston has expanded, rainwater infiltration in the region has lessened and [[aquifer]] extraction increased, causing the depletion of underground aquifers. When the saturated ground dries, the soil can be compressed and the land surface elevation decreases in a process called [[subsidence]]. Subsidence can also occur due to sediment settling. Specifically, regions to the north and west of the Houston metro have seen {{convert|10|mm|in}} to {{convert|25|mm|in}} of subsidence per year.<ref name="Jiangbo Yu et al">{{cite journal|author = Jiangbo Yu|display-authors=etal|title=Is There Deep-Seated Subsidence in the Houston-Galveston Area?|journal=International Journal of Geophysics|volume=2014|pages=1β11|date=July 2, 2014|doi=10.1155/2014/942834|doi-access=free}}</ref> While oil extraction can cause subsidence, in the Houston-Galveston area, most oil has been extracted from sandstone that has relatively negligible ability to compress once oil has been removed. Thus, oil extraction has not resulted in significant subsidence.<ref name="Jiangbo Yu et al"/> Further, the volume of oil extraction in the Houston area is too low to cause significant subsidence.<ref>{{cite web|title=Oil Wells and Production in Harris County, Texas|url=http://www.texas-drilling.com/harris-county|access-date=December 14, 2017|archive-url=https://web.archive.org/web/20171215111431/http://www.texas-drilling.com/harris-county|archive-date=December 15, 2017|url-status=live}}</ref> Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here. You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Christianpedia:Copyrights for details). Do not submit copyrighted work without permission! Cancel Editing help (opens in new window) Discuss this page