| Morro Rock | |
|---|---|
 Morro Rock looking west | |
| Highest point | |
| Elevation | 581 ft (177 m) NAVD 88[1] |
| Coordinates | 35°22′10″N120°52′03″W / 35.369430653°N 120.867550139°W /35.369430653; -120.867550139[1] |
| Geography | |
  Morro Rock Morro Rock (the United States) Show map of the United States | |
| Parent range | Santa Lucia Range |
| Topo map | USGS Morro Bay South |
| Geology | |
| Rock age | c. 23 million years[2] |
| Mountain type | Volcanic plug |
| Volcanicarc/belt | Nine Sisters |
| Designated | January 1, 1968 |
| Reference no. | 821[3] |
Morro Rock (Salinan:Le'samo;Chumash:Lisamu';Spanish:El Morro)[4][5][6] is avolcanic plug inMorro Bay, California, on thePacific Coast at the entrance to Morro Bay harbor. Acauseway connects it with the shore, making it atied island. The rock is protected as the Morro Rock State Preserve.[7]
The 581-foot (177 m)[1] Morro Rock is one of 13volcanic plugs (remnant necks of extinct volcanoes),lava domes, and sheetlike intrusions between Morro Bay on the north andIslay Hill on the south, all inSan Luis Obispo County.[8]
It is composed mostly ofdacite, anigneous, volcanic rock. It is agroundmass ofplagioclase, withamphibole (hornblende),biotite,pyroxene (augite),quartz, andglass; it also includesphenocrysts of plagioclase. Itssilicon dioxide (SiO2) content ranges from 63 to 69 percent.
The dacite volcanic plugs,lava domes,intrusive sheets, and felsiticrhyolite-dacite between Morro Rock and Islay Hill are part of the Morro Rock-Islay Hill Complex of theOligocene epoch (from 27 to 23 million years ago). The complex lies east of theSan Gregorio-San Simeon-Hosgri fault (the SG-SS-H fault). This complex is one of three probable sources of the volcanicclasts within thesandstone andconglomerate of theMiguelito andEdna members of thePismo Formation in thePoint Sur area 145–160 km (90-100 mi) to the north and west of the SG-SS-H fault. Based onpaleomagnetic signatures, the Morro Rock-Islay Hill Complex was rotated 40 to 50 degrees, perhaps during lateMiocene or earlyPliocene time.[9]
TheSalinan andChumash tribes consider Morro Rock to be a sacred site. The Salinan name for Morro Rock isLe'samo and the Chumash name isLisamu.[10]
The Chumash had an important nearby prehistoric settlement at least as early as theMillingstone Horizon (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.[11] 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.[12] 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.[13]
Morro Rock was probably seen by Spanish maritime explorers as early as 1542 underJuan Rodríguez Cabrillo, but its current name was given during the first European land exploration ofAlta California. The SpanishPortolá expedition came down Los Osos Valley and camped near today's Morro Bay on September 8, 1769.Franciscan missionary and expedition memberJuan Crespí noted in his diary that "we saw a great rock in the form of a round mountain (Spanish:morro)".[14][15]
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.[16] 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 declaredCalifornia Historical Landmark number 821.[3][11]
Several types of birds nest on Morro Rock, including threecormorant species and twogull species.[17] It presently serves as a reserve forperegrine falcons, which are locallyendangered and cause most of the laws that prohibit intervention with avian life.
Sea lions andsea otters can be seen regularly in the water around the rock.[18]Seals, however, are much more common in the nearbyMorro Bay State Park, where they breed.
Other fauna include a wide selection oftide pool animals, likehermit crabs, small fish,starfish,sea cucumbers,mussels,bivalvemollusks,coral, and more.
On land fewflora can survive the harsh, dry environment on the rock, but in the surrounding bay,kelp,sea grass,kelp forest plants, and tide pool plants can survive, and a few common grasses,mosses,lichens andweeds from the mainland take root on the rock itself.
Morro Bay State Marine Recreational Management Area and Morro Bay State Marine Reserve are protected areas offshore from Morro Bay. Like underwater parks, protected areas help conserve ocean wildlife and marine ecosystems.
InCyberpunk 2077, 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.
