Roca Partida

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Coordinates: 18°59′50″N 112°03′54″W / 18.99722°N 112.06500°W / 18.99722; -112.06500

Revillagigedo Islands.

Roca Partida (English: Split Rock) ranks as the smallest of the four Revillagigedo Islands, part of the Free and Sovereign State of Colima in Mexico. This uninhabited island encompasses an extremely small area, and many divers rank it among the most beautiful in Mexico. Divers must obtain permits from the Mexican Armed Forces to enter into this military zone.


The higher northwestern peak of Roca Partida with the southeastern peak hidden.
Front view of Roca Partida

The four Revillagigedo Islands originated as volcanoes. San Benedicto Island and Socorro Island erupted in 1953 and 1993, respectively. Clarion Island and Roca Partida lack recently known eruptions. Erosion over millennia reduced Roca Partida to a piece of bare rock, devoid of terrestrial vegetation.

Roca Partida, 100 metres (300 ft) long and 8 metres (26 ft) wide, rises into two peaks. A low-lying bare rock area divides these two peaks, hence the name "Split Rock." The two peaks measured 25 metres (82 ft) and 34 metres (112 ft) high in 1953, but the higher peak apparently lost several meters (feet) since then, as the photographs illustrate.


Roca Partida lacks fresh water and supports no land animals.[1] Nevertheless, the waters surrounding this islet teem with marine life. Several species of seabird breed on the rock, including Nazca booby, Sula granti, which probably ventures little farther northeast, Northeast Pacific brown booby, Sula leucogaster brewsteri, East Pacific sooty tern, Onychoprion fuscatus crissalis—a doubtfully distinct subspecies, and East Pacific brown noddy, Anous stolidus ridgwayi[2]


The island's first reported sighting was by the Spanish expedition of Ruy López de Villalobos, in November 1542, who charted it with its present-day name.[3][4]


  1. ^ Brattstrom & Howell (1956), CMICD (2007)
  2. ^ Brattstrom & Howell (1956)
  3. ^ Brand, Donald D. (1967). Friis, Herman R. (ed.). The Pacific Basin. A History of its Geographical Exploration. New York: American Geographical Society. p. 122.
  4. ^ Martinez Shaw, Carlos (1999). Relación del viaje que hizo desde Nueva España a las Islas de Poniente, despues Filipinas, Ruy López de Villalobos, de orden del Virrey de Nueva España, Don Antonio de Mendoza / García de Escalante Alvarado. Santander: Universidad de Cantabria. p. 41. ISBN 84-8102-234-9.

External links[edit]