Editing Gulf of California (section)

==Geography==

===History===
The marine expeditions of [[Fortún Ximénez]],<ref>{{Cite journal|url=https://doi.org/10.2307/1007225|doi=10.2307/1007225|jstor=1007225|title=The Mythological Geography of California: Origins, Development, Confirmation and Disappearance|last1=Mathes|first1=W. Michael|journal=The Americas|year=1989|volume=45|issue=3|pages=315–341|s2cid=130939548 }}</ref> [[Hernán Cortés]],<ref>Fujita, Harumi. “Prehistoric Occupation of Espíritu Santo Island, Baja California Sur, Mexico: Update and Synthesis.” ''Journal of California and Great Basin Anthropology'', vol. 30, no. 1, Malki Museum, Inc., 2010, p. 18., [http://www.jstor.org/stable/23215633 JSTOR website] Retrieved 18 March 2022.</ref> [[Juan Rodríguez Cabrillo]],<ref>Burckhalter, David, et al. “Early Attempts to Colonize Baja California.” ''Baja California Missions: In the Footsteps of the Padres'', University of Arizona Press, 2013, pp. 15–18, [http://www.jstor.org/stable/j.ctt180r2gc.11 JSTOR website] Retrieved 18 March 2022.</ref> [[Francisco de Ulloa]],<ref>Montané Martí, Julio C, Francisco Preciado, and Francisco Noguerol de Ulloa. Francisco De Ulloa: Explorador De Ilusiones. Hermosillo, Sonora, México: Universidad de Sonora, 1995 [https://hdl.handle.net/2027/txu.059173004270511?urlappend=%3Bseq=5 HathiTrust website] Retrieved 18 March 2022.</ref> [[Hernando de Alarcón]], Captain Francisco de Lucenilla,<ref>Lucenilla, y T. F, Carranco J. Cavallero, Juan B. Ramirez, and Antonio S. Toledo. "Report of the Voyage of Captain Francisco De Lucenilla to the Californias in 1668" (1668). Manuscript. Newberry Library.</ref> and [[Sebastián Vizcaíno]] document its earliest record.<ref>Griffin, George Butler, and Sebastian Vizcaino. “[Report Which Sebastian Vizcaino Makes for the Information of the King of Spain Concerning His Expedition to the Gulf of California—Written Early in 1597].” ''Publications of the Historical Society of Southern California'', vol. 2, no. 1, [University of California Press, Historical Society of Southern California], 1891, pp. 35–52, [https://doi.org/10.2307/41215034 JSTOR website] Retrieved 18 March 2022.</ref> [[Juan de Oñate]] reached the gulf overland in 1605 by following the [[Colorado River]].<ref>Kessell, John L. “‘To See Such Marvels with My Own Eyes’: Spanish Exploration in the Western Borderlands.” ''Montana: The Magazine of Western History'', vol. 41, no. 4, Montana Historical Society, 1991, pp. 68–75, [http://www.jstor.org/stable/4519429 JSTOR website] Retrieved 18 March 2022.</ref> In the 19th century [[Eugène Duflot de Mofras|Duflot de Mofras]] of France and [[Charles Henry Gilbert|C.H. Gilbert]] of the [[United States Fish Commission]] visited the area.<ref>Pipes, Nellie Bowden. “Extract from Exploration of the Oregon Territory, the Californias, and the Gulf of California, Undertaken during the Years 1840, 1841 and 1842 by Eugene Duflot de Mofras.” ''The Quarterly of the Oregon Historical Society'', vol. 26, no. 2, Oregon Historical Society, 1925, pp. 151–90, [http://www.jstor.org/stable/20610311 JSTOR website] Retrieved 18 March 2022.</ref><ref>Hastings, Philip A., et al. “Fishes of the Gulf of California.” ''The Gulf of California: Biodiversity and Conservation'', edited by Richard C. Brusca, University of Arizona Press, 2010, pp. 96–118, [http://www.jstor.org/stable/j.ctt181hwrc.9 JSTOR website] Retrieved 18 March 2022.</ref>

===Area===
The [[International Hydrographic Organization]] defines the southern limit of the gulf as: "A line joining Piaxtla Point (latitude 23°38'N) on the west coast of the mainland of Mexico, and the southern extreme of Lower California".<ref>{{cite web|url=https://iho.int/uploads/user/pubs/standards/s-23/S-23_Ed3_1953_EN.pdf|title=Limits of Oceans and Seas, 3rd edition|year=1953|publisher=[[International Hydrographic Organization]]|page=35|access-date=28 December 2020|archive-url=https://web.archive.org/web/20111008191433/http://www.iho-ohi.net/iho_pubs/standard/S-23/S23_1953.pdf|archive-date=2011-10-08}}</ref>

The gulf is {{convert|1126|km|abbr=on}} long and {{convert|48|-|241|km|abbr=on}} wide, with an area of {{convert|177000|km2|abbr=on}}, a mean depth of {{convert|818.08|m|abbr=on}}, and a volume of {{convert|145000|km3|cumi|abbr=on}}.<ref name="Nix">{{cite web |title=The Gulf of California: A Physical, Geological, and Biological Study |author=Rebekah K. Nix |url=http://www.utdallas.edu/~rnix/MAT-SE_Units/gulf_cal.pdf |publisher=University of Texas at Dallas |access-date=April 10, 2010}}</ref>

The Gulf of California is divided into three faunal regions: Northern, Central, and Southern.{{Citation needed|date=July 2024}}

One recognized transition zone is termed the Southwestern Baja California peninsula. Transition zones exist between faunal regions, and they usually vary for each individual species. (Faunal regions are distinguishable based on the specific types of animals found there.<ref>{{cite web |title=The Gulf of California Invertebrate Database: The Invertebrate Portion of the Macrofauna Golfo Database |publisher=[[Arizona-Sonora Desert Museum]]: Center for Sonoran Desert Studies |url=http://www.desertmuseum.org/center/seaofcortez/database.php}}
</ref>)

===Geology===
[[File:Gulf of California.jpg|300px|thumbnail|Satellite picture of the gulf]]
Geologic evidence is widely interpreted by geologists as indicating the gulf came into being around 5.3 million years ago as [[plate tectonics|tectonic forces]] rifted the [[Baja California peninsula]] off the [[North American plate]].<ref>[[Warren B. Hamilton|Hamilton, W.B.]], 1961, Origin of the Gulf of California: GSA Bull., 72, 1307–1318.</ref> As part of this process, the [[East Pacific Rise]] propagated up the middle of the Gulf along the seabed. This extension of the East Pacific Rise is often referred to as the [[Gulf of California Rift Zone]]. The Gulf would extend as far as [[Indio, California]], except for the tremendous [[river delta|delta]] created by the [[Colorado River]]. This delta blocks the sea from flooding the [[Mexicali]] and [[Imperial Valley]]s. Volcanism dominates the [[East Pacific Rise]]. The island of [[Tortuga Island, Baja California Sur|Isla Tortuga]] is one example of this ongoing volcanic activity.<ref>{{cite web |url=http://review.nsf-margins.org/SPRCL.html |title=Science Plans RCL |publisher=review.nsf-margins.org |access-date=May 27, 2008 |archive-date=February 18, 2009 |archive-url=https://web.archive.org/web/20090218231705/http://review.nsf-margins.org/SPRCL.html |url-status=dead }}</ref> Furthermore, [[hydrothermal vent]]s due to extension tectonic regime, related to the opening of the gulf, are found in the Bahía de Concepción, Baja California Sur.<ref>{{Cite journal|last=Leal-Acosta, M.L., Prol-Ledesma, R.M.|year=2016|title=Caracterización geoquímica de las manifestaciones termales intermareales de Bahía Concepción en la Península de Baja California|journal=Boletín de la Sociedad Geológica Mexicana|language=es|volume=68|issue=3|pages=395–407|doi=10.18268/BSGM2016v68n3a2|doi-access=free}}</ref>

===Islands===
{{see also|List of islands of Mexico#Gulf of California}}
The gulf contains 37 major islands, the two largest being [[Isla Ángel de la Guarda]] and [[Tiburón Island|Isla Tiburón]]. Most of the islands are found on the west side of the gulf. In fact, many of the islands of the gulf are the result of volcanic eruptions that occurred during the early history of Baja California. The islands of [[Islas Marías]], Islas San Francisco, and [[Isla Partida]] are thought to be the result of such eruptions. The formations of the islands, however, are not dependent on each other. They were each formed as a result of an individual structural occurrence.<ref name="Brusca"/> Several islands, including [[Isla Coronados]], are home to volcanoes. The [[Colorado River Delta]] contains several islands, such as [[Isla Montague]].

The gulf has more than 900 islets and islands which together total about 420 hectares. All of them as a whole were enacted as "Area Reserve and Migratory Bird Refuge and Wildlife" on August 2, 1978. In June 2000, the islands were designated a [[Mexican Flora and Fauna Protection Areas|flora and fauna protection area]]. In addition to this effort by the Mexican government, for its importance and recognition worldwide, all islands in the gulf are also part of the international program "Man and Biosphere" (MAB) and are part of the World Reserve Network UNESCO Biosphere as Special Biosphere Reserve. Because of the vast expanse covered by this federal protected area, conservation and management is carried out through a system of four regional directorates (one per state bordering the Gulf of California). The work of direct and indirect conservation done in the islands is governed by a single management program, published in 2000, which is complemented by local and specific management programs. The Directorate of Protection Area Wildlife California Gulf Islands in Baja California is responsible for 56 islands located off the coast of the state. These are grouped into four archipelagos: San Luis Gonzaga or Enchanted, Guardian Angel, Bahía de los Ángeles and San Lorenzo.<ref>{{cite web|url=http://www.mexicodesconocido.com.mx/valle-de-los-cirios.-tesoro-de-baja-california.html|title=Valle de los Cirios. Tesoro de Baja California|date=14 July 2010}}</ref><ref>{{cite web|url=http://islasgc.conanp.gob.mx/islas/|title=Área de Protección de Flora y Fauna Islas del Golfo de California en Baja California|access-date=2016-06-27|archive-url=https://web.archive.org/web/20150328022637/http://islasgc.conanp.gob.mx/islas/|archive-date=2015-03-28|url-status=dead}}</ref>

===Shores and tides===
The three general types of shores found in the gulf include [[rocky shore]], sandy beach, and tidal flat.

Some of the rich biodiversity and high [[endemism]] that characterize the gulf and make it such a hotspot for fishing can be attributed to seemingly insignificant factors, such as the types of rocks that make up a shore. Beaches with softer, more porous rocks (such as [[coquina]] limestone, [[rhyolite]]s, [[granite]], or [[diorite]]) generally have a higher species richness than those with harder, smoother rocks (such as [[basalt]] or [[diabase]]). Porous rocks will naturally have more cracks and crevices in them, making them ideal living spaces for many animals. The rocks themselves, however, generally need to be stable on the shore for a habitat to be stable. Additionally, the color of the rocks can affect the organisms living on a shore. For example, darker rocks will be significantly warmer than lighter ones, and can deter animals that do not have a high tolerance for heat.<ref name="Brusca" />

The northern gulf experiences tidal ranges of up to {{convert|5|m|abbr=on}}. Mixed [[semidiurnal tides]] are the norm throughout most of the Gulf.

===Estuaries===
There are a number of negative [[estuary|estuaries]], that is, ones in which the evaporation of seawater is relatively greater than that of the fresh water input. The salinities of these inlets are higher than that of the ocean. The temperatures, [[Poikilotherm#Ecological niches|poikilothermal]], of these negative estuaries also are higher than the general temperature of the gulf. It is possible that at one time these estuaries were positive, that is, ones in which the [[seawater]] component is diluted; therefore, the water is [[brackish water|brackish]], with salinity less than that of the ocean. However, because of human settlement around the gulf and water diversion for municipal and agricultural use in an area of comparatively low rainfall, there are no longer many rivers that freely empty into the gulf. The upper [[Colorado River Delta]] is one example of a historically major estuary and [[wetland]]s ecosystem, that since the 20th century construction of upriver dams and diversion aqueducts on the Colorado River, is now a small [[Ephemerality|ephemeral]] remnant estuary. The remaining gulf inlets still are important to several species of fishes, crustaceans, and shellfish that are commercially harvested.<ref name="Brusca"/>