Farallon de Pajaros

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  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 20.538°N
  • 144.896°E

  • 360 m
    1181 ft

  • 284140
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

The Global Volcanism Program has no activity reports for Farallon de Pajaros.

The Global Volcanism Program has no Weekly Reports available for Farallon de Pajaros.

Index of Monthly Reports

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

09/1981 (SEAN 06:09) Normal fuming and discolored water

10/1990 (BGVN 15:10) Vigorous fuming

06/1992 (BGVN 17:06) Vigorous fuming


Contents of Monthly Reports

All information contained in these reports is preliminary and subject to change.

All times are local (= UTC + 10 hours)

09/1981 (SEAN 06:09) Normal fuming and discolored water

"A 16 July USN flight also covered the Quaternary volcanoes of the Marianas. Fuming and discolored water were observed at Farallon de Pajaros but were not anomalous conditions."

Information Contacts: N. Banks, HVO.

10/1990 (BGVN 15:10) Vigorous fuming

"Photographs taken by Civil Defense personnel in early August 1990 from a fixed-wing airplane showed vigorous fuming."

Information Contacts: R. Moore, USGS; R. Koyanagi and M. Sako, HVO.

06/1992 (BGVN 17:06) Vigorous fuming

When observed from an airplane on 13 May, the volcano continued to fume vigorously, but no active lava was seen.

Information Contacts: R. Moore, USGS; R. Koyanagi, M. Sako, and F. Trusdell, HVO.

The small 2-km-wide island of Farallon de Pajaros (also known as Uracas) is the northernmost and most active volcano of the Mariana Islands. Its relatively frequent historical eruptions dating back to the mid-19th century have caused the andesitic volcano to be referred to as the "Lighthouse of the western Pacific." The symmetrical, sparsely vegetated summit is the central cone within a small caldera cutting an older edifice, remnants of which are seen on the SE and southern sides near the coast. Flank fissures have fed lava flows during historical time that form platforms along the coast. Both summit and flank vents have been active at Farallon de Pajaros during historical time. Eruptions have also been observed from nearby submarine vents, and Makhahnas seamount, which rises to within 640 m of the sea surface, lies about 10 km to the SW.

Summary of Holocene eruption dates and Volcanic Explosivity Indices (VEI).

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1967 Mar 27 1967 Apr 10 Confirmed 0 Hydrophonic SW of Uracas (Makhahnas seamount)
1952 Oct 26 ± 5 days 1953 Apr 15 Confirmed 2 Historical Observations Summit, east side
1951 Aug Unknown Confirmed 2 Historical Observations
1947 Jan (?) Unknown Confirmed 0 Historical Observations North side
1943 Unknown Confirmed 2 Historical Observations Summit, south side
1941 Mar 28 Unknown Confirmed   Historical Observations
1939 Unknown Confirmed 2 Historical Observations East side ?
1936 Apr 15 ± 45 days Unknown Confirmed 2 Historical Observations
1934 Jul 15 ± 45 days Unknown Confirmed 0 Historical Observations Immediately south of Uracas
1932 Sep 7 1932 Oct 7 Confirmed 2 Historical Observations Summit, east side ?
1928 Dec 15 ± 5 days Unknown Confirmed 2 Historical Observations
1925 Unknown Confirmed 2 Historical Observations
1912 Unknown Confirmed 2 Historical Observations North side ?
1900 (?) 1901 May Confirmed 2 Historical Observations Summit, east side
1874 (?) 1876 Jan 3 (in or after) Confirmed 2 Historical Observations Summit, NE side
[ 1865 ] [ Unknown ] Discredited    
1864 Jan 7 Unknown Confirmed 2 Historical Observations SW side

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.



Synonyms
Uracas | Pajaros | Uraccas


Craters
Feature Name Feature Type Elevation Latitude Longitude
Makhahnas Submarine crater -640 m 20° 28' 0" N 144° 51' 0" E
Explosive activity was frequently observed from Farallon de Pajoras volcano in October and November 1952. Lava flows were emplaced on the east and west sides of the summit in February-March 1953. This 1953 photo from the east shows an eruption plume rising above the summit crater and lighter-gray lava flows in the center that were erupted in 1953. The lobe just left of center eventually reached the coast. Explosive activity continued until April 15. The steep-sided peak at the SE coastline is a remnant of an older caldera.

Photo by U.S. Navy, 1953.
The small 2-km-wide island of Farallon de Pajaros (Uracas) is the northernmost and most active volcano of the Mariana Islands. It has been referred to as the "Lighthouse of the western Pacific." The symmetrical, sparsely vegetated central cone lies within a caldera, remnants of which form the prominent peak seen here in 1980 at the center along the SE coast. Flank fissures from historical eruptions have fed lava flows that form platforms along the coast. Both summit and flank vents have been active during historical time.

Photo by Winfrey, 1980 (U.S. Navy).
The small island volcano of Farallón de Pájaros (Uracas) is surrounded by a series of lava flows erupted during historical time. This 1980 photo from the SE shows a blanket of unvegetated lava flows at the left that diverted around the prominent vegetated peak at the lower right. It is a remant of a caldera created prior to the formation of the present cone.

Photo by Winfrey (U.S. Navy), 1980.
Ahyi seamount (upper right) is a large conical submarine volcano that rises to within 137 m of the sea surface about 18 km SE of the island of Farallon de Pajaros (left-center). At various times since 1979, water discoloration, felt shocks followed by upwelling of sulfur-bearing water, and a seismically detected submarine eruption have been reported at or near Ahyi seamount. Two submarine volcanoes on the flanks of Farallon de Pajaros, Northwest Uracas and Makhahnas, are seen in this NOAA bathymetric image.

Image courtesy of NOAA, 2003 (http://oceanexplorer.noaa.gov/explorations/03fire/logs/mar02/media/nikko.html).

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.

Bloomer S H, Stern R J, Smoot N C, 1989. Physical volcanology of the submarine Mariana and Volcano arcs. Bull Volc, 51: 210-224.

Corwin G, 1971. Quaternary volcanics of the Mariana Islands. Unpublished manuscript, 137 p.

Green J, Short N M, 1971. Volcanic Landforms and Surface Features: a Photographic Atlas and Glossary. New York: Springer-Verlag, 519 p.

Katsui Y (ed), 1971. List of the World Active Volcanoes. Volc Soc Japan draft ms, (limited circulation), 160 p.

Kuno H, 1962. Japan, Taiwan and Marianas. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 11: 1-332.

Volcano Types

Stratovolcano
Caldera

Tectonic Setting

Subduction zone
Crustal thickness unknown

Rock Types

Major
Andesite / Basaltic Andesite

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km
0
0
0
0

Affiliated Databases

Large Eruptions of Farallon de Pajaros Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
WOVOdat WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.
EarthChem EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).
Smithsonian Collections Search the Smithsonian's NMNH Department of Mineral Sciences collections database. Go to the "Search Rocks and Ores" tab and use the Volcano Name drop-down to find samples.