Editing Central Valley (California) (section)

==Geology==
[[File:Interstate 5 Southbound near Derrick Ave.JPG|thumb|The valley as seen from [[Interstate 5 in California|Interstate 5]], looking south near Derrick Avenue in [[Fresno County, California|Fresno County]]]]
The flatness of the valley floor contrasts with the rugged hills or gentle mountains that are typical of most of California's terrain. The valley is thought to have originated below sea level as an offshore area depressed by [[subduction]] of the [[Farallon Plate]] into a trench farther offshore. The valley has no earthquake faults of its own but is surrounded by faults to the east and west.

[[File:I-5 between Tracy and Patterson CA.jpg|thumb|right|An example of the differences between the geology of the valley floor and that of the rugged hills of the Coast Ranges (Between Tracy and Patterson, CA:Interstate 5)]]
The valley was enclosed by the uplift of the [[Coast Ranges]], with its original outlet into [[Monterey Bay]]. Faulting moved the Coast Ranges, and a new outlet developed near what is now [[San Francisco Bay]]. Over the millennia, the valley filled with the sediments of these same ranges, as well as the rising [[Sierra Nevada (U.S.)|Sierra Nevada]] to the east; that filling eventually created an extraordinary flatness just barely above sea level. Before California's flood control and aqueduct system was built, annual snow melt turned much of the valley into an inland sea.

The one notable exception to the flat valley floor is [[Sutter Buttes]], the remnants of an extinct volcano just to the northwest of [[Yuba City, California|Yuba City]].

Another significant geologic feature of the Central Valley lies hidden beneath the delta. The [[Stockton Arch]] is an upwarping of the crust beneath the valley sediments that extends southwest to northeast across the valley.

The Central Valley lies within the California Trough physiographic section, which is part of the larger Pacific Border province, which in turn is part of the [[Geography of the United States Pacific Mountain System|Pacific Mountain System]].<ref name="USGS-Water">{{cite web | title = Physiographic divisions of the conterminous U. S. | publisher = U.S. Geological Survey | url = http://water.usgs.gov/GIS/metadata/usgswrd/XML/physio.xml | access-date = December 6, 2007 | url-status = live | archive-url = https://web.archive.org/web/20071205095639/http://water.usgs.gov/GIS/metadata/usgswrd/XML/physio.xml | archive-date = December 5, 2007 }}</ref><ref>{{Cite book |last1=Benke |first1=Arthur C. |last2=Cushing |first2=Colbert E. |title=Rivers of North America |publisher=Academic Press |year=2005 |page=[https://archive.org/details/riversofnorthame0000unse/page/554 554] |isbn=0-12-088253-1 |url=https://archive.org/details/riversofnorthame0000unse/page/554 }}</ref>

Excessive groundwater pumping in Central Valley has caused measurable amounts of [[Central valley land subsidence|land subsidence in recent years]].<ref>{{Cite web |title=California's San Joaquin Valley is sinking at record-breaking rates, new study shows |url=https://news.stanford.edu/stories/2024/11/groundwater-pumping-drives-rapid-sinking-in-california |access-date=2025-01-11 |website=news.stanford.edu |language=en}}</ref>