Morro Rock (

Salinan The Salinan are a Native American tribe whose ancestral territory is in the southern Salinas Valley and the Santa Lucia Range in the Central Coast of California. Today, the Salinan governments are now working toward federal tribal recognition ...

: ''Le'samo; ''

Chumash Chumash may refer to: *Chumash (Judaism), a Hebrew word for the Pentateuch, used in Judaism *Chumash people, a Native American people of southern California *Chumashan languages, Indigenous languages of California See also

* Pentateuch (dis ...

: ''Lisamu''';

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many countries in the Americas **Spanish cuisine **Spanish history **Spanish culture ...

: ''El Morro'') is a

volcanic plug A volcanic plug, also called a volcanic neck or lava neck, is a volcano, volcanic object created when magma hardens within a Volcanic vent, vent on an active volcano. When present, a plug can cause an extreme build-up of high gas pressure if risi ...

Morro Bay, California Morro Bay (''Morro'', Spanish for "Hill") is a seaside city in San Luis Obispo County, California, United States. Located on the Central Coast of California, the city's population was 10,757 as of the 2020 census, up from 10,234 at the 2010 ...

, on the

Pacific Coast Pacific coast may be used to reference any coastline that borders the Pacific Ocean. Geography Americas North America Countries on the western side of North America have a Pacific coast as their western or south-western border. One of th ...

at the entrance to Morro Bay harbor. A

causeway A causeway is a track, road or railway on the upper point of an embankment across "a low, or wet place, or piece of water". It can be constructed of earth, masonry, wood, or concrete. One of the earliest known wooden causeways is the Sweet T ...

connects it with the shore, making it a

tied island A tied island or land-tied island is a landform consisting of an island that is connected to the mainland or another island only by a tombolo, which is a spit of beach materials connected to land at both ends. St Ninian's Isle in the Shetlan ...

. The rock is protected as the Morro Rock State Preserve.

Geology

The Morro Rock is one of 13

s (remnant necks of extinct volcanoes),

lava domes In volcanology, a lava dome is a circular, mound-shaped protrusion resulting from the slow Extrusive rock, extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6 ...

, and sheetlike intrusions between Morro Bay on the north and Islay Hill on the south, all in

San Luis Obispo County San Luis Obispo County (), officially the County of San Luis Obispo, is a county on the Central Coast of California. As of the 2020 United States census, the population was 282,424. The county seat is San Luis Obispo. Junípero Serra fou ...

. It is composed mostly of

dacite Dacite () is a volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides. It has a fine-grained (aphanitic) to porphyritic texture and is intermediate in composition between andesite and rhyolite. ...

, an

igneous Igneous rock ( ), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rocks are formed through the cooling and solidification of magma or lava. The magma can be derived from partial ...

, volcanic rock. It is a

groundmass The matrix or groundmass of a rock is the finer-grained mass of material in which larger grains, crystals, or clasts are embedded. The matrix of an igneous rock consists of finer-grained, often microscopic, crystals in which larger crystals, ...

plagioclase Plagioclase ( ) is a series of Silicate minerals#Tectosilicates, tectosilicate (framework silicate) minerals within the feldspar group. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a continu ...

, with

amphibole Amphibole ( ) is a group of inosilicate minerals, forming prism or needlelike crystals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Its IMA symbol is ...

(hornblende),

biotite Biotite is a common group of phyllosilicate minerals within the mica group, with the approximate chemical formula . It is primarily a solid-solution series between the iron- endmember annite, and the magnesium-endmember phlogopite; more al ...

pyroxene The pyroxenes (commonly abbreviated Px) are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. Pyroxenes have the general formula , where X represents ions of calcium (Ca), sodium (Na), iron ( ...

(augite),

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tet ...

, and

glass Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window pane ...

; it also includes

phenocrysts 300px, Swiss side of the Mont Blanc massif, has large white phenocrysts of plagioclase (that have trapezoid shapes when cut through). 1 euro coin (diameter 2.3 cm) for scale. A phenocryst is an early forming, relatively large and usually conspic ...

of plagioclase. Its

silicon dioxide Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundan ...

(SiO2) content ranges from 63 to 69 percent. The dacite volcanic plugs,

, intrusive sheets, and felsitic

rhyolite Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture (geology), texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained matri ...

-dacite between Morro Rock and Islay Hill are part of the Morro Rock-Islay Hill Complex of the

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

epoch (from 27 to 23 million years ago). The complex lies east of the San Gregorio-San Simeon-Hosgri fault (the SG-SS-H fault). This complex is one of three probable sources of the volcanic

clasts Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks b ...

within the

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

and conglomerate of the Miguelito and Edna members of the Pismo Formation in the Point Sur area to the north and west of the SG-SS-H fault. Based on paleomagnetic signatures, the Morro Rock-Islay Hill Complex was rotated 40 to 50 degrees, perhaps during late

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

or early

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Salinan The Salinan are a Native American tribe whose ancestral territory is in the southern Salinas Valley and the Santa Lucia Range in the Central Coast of California. Today, the Salinan governments are now working toward federal tribal recognition ...

and

* Pentateuch (dis ...

tribes consider Morro Rock to be a sacred site. The Salinan name for Morro Rock is ''Le'samo'' and the Chumash name is ''Lisamu''. The Chumash had an important nearby prehistoric settlement at least as early as the

Millingstone Horizon Millingstone Horizon is an archaeological period of Native American dominance denoting a period in California, United States involving extensive use of manos and other grinding technology. The interval is a subset of the Archaic Period; speci ...

(6500-2000 B.C.E.), and the village was near the mouth of Morro Creek, at the current site of Morro Bay High School. The right of the Salinan people to climb Morro Rock for their biannual solstice ceremonies has been established, in which they celebrate the time in legend when a hawk and a raven destroyed a two-headed serpent-monster Taliyekatapelta as he wrapped his body around the base of the rock. The established Salinan right to climb the rock has been in legal dispute by the local Chumash tribe, which claims that Morro Rock is Chumash, not Salinan, territory. The Chumash also believe that the rock is so sacred that it should never be climbed. Because of its fragility, it is illegal for the general public to climb it.

European sighting

Morro Rock was probably seen by Spanish maritime explorers as early as 1542 under

Juan Rodríguez Cabrillo Juan Rodríguez Cabrillo (; 1497 – January 3, 1543) was a Portuguese maritime explorer best known for investigations of the west coast of North America, undertaken on behalf of the Spanish Empire. He was the first European to explore presen ...

, but its current name was given during the first European land exploration of

Alta California Alta California (, ), also known as Nueva California () among other names, was a province of New Spain formally established in 1804. Along with the Baja California peninsula, it had previously comprised the province of , but was made a separat ...

. The Spanish

Portolá expedition thumbnail, 250px, Point of San Francisco Bay Discovery The Portolá expedition was a Spanish voyage of exploration in 1769–1770 that was the first recorded European exploration of the interior of the present-day California. It was led by Gas ...

came down Los Osos Valley and camped near today's Morro Bay on September 8, 1769.

Franciscan The Franciscans are a group of related organizations in the Catholic Church, founded or inspired by the Italian saint Francis of Assisi. They include three independent Religious institute, religious orders for men (the Order of Friars Minor bei ...

missionary and expedition member

Juan Crespí Juan Crespí, OFM (Catalan language, Catalan: ''Joan Crespí''; 1 March 1721 – 1 January 1782) was a Franciscan missionary and explorer of The Californias, Las Californias. Biography A native of Majorca, Crespí entered the Franciscan ord ...

noted in his diary that "we saw a great rock in the form of a round mountain (''Spanish: morro'')".

Quarry and historical landmark

The rock, which was quarried on and off from 1889 to 1969, provided material for the breakwater of Morro Bay and the improvements at Port San Luis Harbor. In 1966, a state law was adopted that transferred title to the State of California. In February 1968, the San Luis Obispo County Historical Society and the City of Morro Bay succeeded in having Morro Rock declared

California Historical Landmark A California Historical Landmark (CHL) is a building, structure, site, or place in the U.S. state of California that has been determined to have statewide historical landmark significance. Criteria Historical significance is determined by meetin ...

number 821.

Flora and fauna

Several types of birds nest on Morro Rock, including three

cormorant Phalacrocoracidae is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags. Several different classifications of the family have been proposed, but in 2021 the International Ornithologists' Union (IOU) ado ...

species and two

gull Gulls, or colloquially seagulls, are seabirds of the subfamily Larinae. They are most closely related to terns and skimmers, distantly related to auks, and even more distantly related to waders. Until the 21st century, most gulls were placed ...

species.Joan Easton Lentz and Don DesJardin (2006) ''Introduction to Birds of the Southern California Coast'', University of California Press, 316 pages It presently serves as a reserve for

peregrine falcons The peregrine falcon (''Falco peregrinus''), also known simply as the peregrine, is a cosmopolitan bird of prey (raptor) in the family Falconidae renowned for its speed. A large, crow-sized falcon, it has a blue-grey back, barred white underpa ...

, which are locally

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...

and cause most of the laws that prohibit intervention with avian life.

Sea lions Sea lions are pinnipeds characterized by external ear flaps, long foreflippers, the ability to walk on all fours, short and thick hair, and a big chest and belly. Together with the fur seals, they make up the family Otariidae, eared seals. ...

and

sea otter The sea otter (''Enhydra lutris'') is a marine mammal native to the coasts of the northern and eastern Pacific Ocean, North Pacific Ocean. Adult sea otters typically weigh between , making them the heaviest members of ...

s can be seen regularly in the water around the rock.

Seals Seals may refer to: * Pinniped, a diverse group of semi-aquatic marine mammals, many of which are commonly called seals, particularly: ** Earless seal, or "true seal" ** Fur seal * Seal (emblem), a device to impress an emblem, used as a means of a ...

, however, are much more common in the nearby

Morro Bay State Park Morro Bay State Park is a state park on the Morro Bay, California#Geography, Morro Bay lagoon, in western San Luis Obispo County, California, San Luis Obispo County, on the Central Coast (California), Central Coast of California. On the lagoon's ...

, where they breed. Other fauna include a wide selection of

tide pool A tide pool or rock pool is a shallow pool of seawater that forms on the rocky intertidal shore. These pools typically range from a few inches to a few feet deep and a few feet across. Many of these pools exist as separate bodies of water only ...

animals, like

hermit crab Hermit crabs are anomuran Decapoda, decapod crustaceans of the superfamily (taxonomy), superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their fragile exoskeletons. There are over 800 species of hermit c ...

s, small fish,

starfish Starfish or sea stars are Star polygon, star-shaped echinoderms belonging to the class (biology), class Asteroidea (). Common usage frequently finds these names being also applied to brittle star, ophiuroids, which are correctly referred to ...

sea cucumber Sea cucumbers are echinoderms from the class (biology), class Holothuroidea ( ). They are benthic marine animals found on the sea floor worldwide, and the number of known holothuroid species worldwide is about 1,786, with the greatest number be ...

mussel Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other ...

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

coral Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact Colony (biology), colonies of many identical individual polyp (zoology), polyps. Coral species include the important Coral ...

, and more. On land few

flora Flora (: floras or florae) is all the plant life present in a particular region or time, generally the naturally occurring (indigenous (ecology), indigenous) native plant, native plants. The corresponding term for animals is ''fauna'', and for f ...

can survive the harsh, dry environment on the rock, but in the surrounding bay,

kelp Kelps are large brown algae or seaweeds that make up the order (biology), order Laminariales. There are about 30 different genus, genera. Despite its appearance and use of photosynthesis in chloroplasts, kelp is technically not a plant but a str ...

sea grass Seagrasses are the only flowering plants which grow in marine (ocean), marine environments. There are about 60 species of fully marine seagrasses which belong to four Family (biology), families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and ...

kelp forest Kelp forests are underwater areas with a high density of kelp, which covers a large part of the world's coastlines. Smaller areas of anchored kelp are called kelp beds. They are recognized as one of the most productive and dynamic ecosystems on E ...

plants, and tide pool plants can survive, and a few common grasses,

moss Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryo ...

es,

lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...

s and

weed A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. Pla ...

s from the mainland take root on the rock itself.

Marine protected areas

Morro Bay State Marine Recreational Management Area and Morro Bay State Marine Reserve Morro Bay State Marine Recreational Management Area (SMRMA) and Morro Bay State Marine Reserve (SMR) are two marine protected areas that provide protection for Morro Bay Estuary on California's central coast. The two marine protected areas togeth ...

are protected areas offshore from Morro Bay. Like underwater parks, protected areas help conserve ocean wildlife and marine ecosystems.

In popular culture

In ''

Cyberpunk 2077 ''Cyberpunk 2077'' is a 2020 action role-playing game developed by CD Projekt Red and published by CD Projekt. Based on Mike Pondsmith's ''Cyberpunk (role-playing game), Cyberpunk'' tabletop game series, the plot is set in the fictional metrop ...

'', where Morro Bay is home to the independent city-state of Night City, Morro Rock has been demolished in order to build Night City International and Translunar Spaceport (NCX) between 2045 and 2047.

References

External links

*
City of Morro Bay
{{authority control Nine Sisters . Rock formations of California California State Reserves Volcanic plugs of California Protected areas of San Luis Obispo County, California Landforms of San Luis Obispo County, California Islands of California Volcanoes of California