Editing Berkeley, California (section)

===Geology===
Most of Berkeley lies on a rolling sedimentary plain that rises gently from sea level to the base of the [[Berkeley Hills]]. East of the [[Hayward Fault]] along the base of the hills, elevation increases more rapidly. The highest peak along the ridge line above Berkeley is [[Grizzly Peak (Berkeley Hills)|Grizzly Peak]], at an elevation of {{convert|1754|ft}}. A number of small creeks run from the hills to the Bay through Berkeley: [[Cerrito Creek|Cerrito]], [[Codornices Creek|Codornices]], [[Schoolhouse Creek|Schoolhouse]], and [[Strawberry Creek|Strawberry]] Creeks are the principal streams. Most of these are largely [[culvert]]ed once they reach the plain west of the hills.

The Berkeley Hills are part of the [[Pacific Coast Ranges]], and run in a northwest–southeast alignment. Exposed in the Berkeley Hills are cherts and shales of the Claremont Formation (equivalent to the [[Monterey Formation]]), conglomerate and sandstone of the Orinda Formation and lava flows of the Moraga Volcanics. Of similar age to the Moraga Volcanics (extinct), within the Northbrae neighborhood of Berkeley, are outcroppings of erosion resistant rhyolite. These [[rhyolite]] formations can be seen in several city parks and in the yards of a number of private residences. [[Indian Rock Park]] in the northeastern part of Berkeley near the Arlington/Marin Circle features a large example.

====Earthquakes====
Berkeley is traversed by the [[Hayward Fault Zone]], a major branch of the [[San Andreas Fault]] to the west. No large earthquake has occurred on the Hayward Fault near Berkeley in historic times (except possibly in 1836), but seismologists warn about the geologic record of large temblors several times in the deeper past. The current assessment is that a Bay Area earthquake of magnitude 6.7 or greater within the next 30 years is likely, with the Hayward Fault having the highest likelihood among faults in the Bay Area of being the epicenter.<ref>{{cite web|url = https://earthquake.usgs.gov/regional/nca/ucerf/|title = 2008 Bay Area Earthquake Probabilities|access-date = June 26, 2015|publisher = United States Geological Survey|archive-url = https://web.archive.org/web/20150629012606/http://earthquake.usgs.gov/regional/nca/ucerf/|archive-date = June 29, 2015|url-status = dead}}</ref> Moreover, like much of the Bay Area, Berkeley has many areas of some risk to [[soil liquefaction]], with the flat areas closer to the shore at low to high susceptibility.<ref>{{cite web|url = https://earthquake.usgs.gov/regional/nca/alameda/|title = U.S. Geological Survey Liquefaction Hazard Maps|access-date = February 18, 2015|publisher=United States Geological Survey|archive-url = https://web.archive.org/web/20150219045641/http://earthquake.usgs.gov/regional/nca/alameda/|archive-date = February 19, 2015|url-status = dead}}</ref>

The [[1868 Hayward earthquake]] did occur on the southern segment of the Hayward Fault<ref>{{cite news |url=https://timesmachine.nytimes.com/timesmachine/1868/10/22/87584244.pdf |newspaper=The New York Times |date=October 22, 1868 |title=Earthquake in San Francisco and Neighboring Places |access-date=June 13, 2018 |archive-url=https://web.archive.org/web/20200116005156/https://timesmachine.nytimes.com/timesmachine/1868/10/22/87584244.pdf |archive-date=January 16, 2020 |url-status=dead }}</ref> in the vicinity of today's city of [[Hayward, California|Hayward]]. This quake destroyed the county seat of Alameda County then located in [[San Leandro, California|San Leandro]] and it subsequently moved to Oakland. It was strongly felt in San Francisco, causing major damage. It was regarded as the "Great San Francisco earthquake" prior to 1906. It produced a furrow in the ground along the fault line in Berkeley, across the grounds of the new [[State Asylum for the Deaf, Dumb and Blind]] then under construction, which was noted by one early University of California professor. Although no significant damage was reported to most of the few Berkeley buildings of the time, the 1868 quake did destroy the vulnerable adobe home of Domingo Peralta in north Berkeley.<ref>Lawson, A. C. (ed.), ''The California Earthquake of April 18, 1906'', 1908, Reprinted 1969 by the Carnegie Institution of Washington. This is a comprehensive report on the 1906 earthquake, published by the State Earthquake Investigation Commission, and comprises two volumes and an atlas. It contains a discussion of the 1868 Hayward Fault earthquake and its effects, and includes a number of photos taken by Lawson himself of damage in Berkeley caused by the 1906 quake. The report is available from the USGS. {{cite web |url=https://earthquake.usgs.gov/earthquakes/events/1906calif/18april/references.php |title=1906 Earthquake – References |website=Earthquake.usgs.gov}}</ref>

Today, evidence of the Hayward Fault's "creeping" is visible at various locations in Berkeley. Cracked roadways, sharp jogs in streams, and springs mark the fault's path. However, since it cuts across the base of the hills, the creep is often concealed by or confused with slide activity. Some of the slide activity itself, however, results from movement on the Hayward Fault.

A notorious segment of the Hayward Fault runs lengthwise down the middle of [[California Memorial Stadium|Memorial Stadium]] at the mouth of Strawberry Canyon on the University of California campus.<ref>{{Cite journal|url=https://haywardfaultucberkeley.pressbooks.com/chapter/the-california-memorial-stadium/|title=The California Memorial Stadium|first=Horst|last=Rademacher|website=Haywardfaultucberkeley.pressbooks.com}}</ref> Photos and measurements show the movement of the fault through the stadium.<ref>{{Cite book |last=Rademacher |first=Horst |url=https://earthquakes.berkeley.edu/docs/HF_Tour_Stadium-1.1-Protected.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://earthquakes.berkeley.edu/docs/HF_Tour_Stadium-1.1-Protected.pdf |archive-date=October 9, 2022 |url-status=live |title=The Hayward Fault at the Campus of the University of California, Berkeley: A Guide to a Brief Walking Tour |date=June 6, 2017 |publisher=Berkeley Seismological Laboratory |pages=17–21}}</ref>