- Info & Contacts
The Global Volcanism Program has no activity reports for Ofu-Olosega.
The Global Volcanism Program has no Weekly Reports available for Ofu-Olosega.
The Global Volcanism Program has no Bulletin Reports available for Ofu-Olosega.
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.
|Feature Name||Feature Type||Elevation||Latitude||Longitude|
|A'ofa||Shield volcano||494 m||14° 10' 30" S||169° 39' 47" W|
|Fatuaga Point||Cone||230 m||14° 10' 7" S||169° 38' 18" W|
|Maga Point||Cone||23 m||14° 11' 32" S||169° 36' 45" W|
|Nu'u||Tuff cone||76 m||14° 10' 4" S||169° 41' 5" W|
|Tauga Point||Tuff cone||249 m||14° 9' 48" S||169° 40' 21" W|
There is data available for 1 Holocene eruptive periods.
|Start Date||Stop Date||Eruption Certainty||VEI||Evidence||Activity Area or Unit|
|1866 Sep 12||1866 Nov 15 ± 5 days||Confirmed||2||Historical Observations||Submarine vent 3 km SE of Olosega|
There is no Deformation History data available for Ofu-Olosega.
There is no Emissions History data available for Ofu-Olosega.
|Clouds drape the tops of the two triangle-shaped islands of Ofu (left) and Olosega (right) in eastern Samoa in this Space Shuttle image (with north to the upper left). The islands, 6 km in combined length, are separated by a narrow strait. They are formed by two eroded, coalescing basaltic shield volcanoes truncated by mostly submarine calderas. A submarine eruption took place in 1866 about 3 km SE of Olosega, along the ridge connecting Olosega with Ta'u Island.
NASA Space Shuttle image ISS002-E-6878, 2001 (http://eol.jsc.nasa.gov/).
|A narrow strait (just left of center) separates the two triangle-shaped islands of Ofu (left) and Olosega (right) in eastern Samoa. The islands are formed by two eroded, coalescing basaltic shield volcanoes. The narrow, steep-sided ridge forming the western side of Ofu Island is cut by volcanic dikes, and an intrusive plug forms the sharp spire at the left on Ofu Island. A submarine eruption took place in 1866 at the far end of the two islands, 3 km SE of Olosega, along the ridge connecting Olosega with Ta'u Island.
Photo by Peter Craig, 1995 (U.S. National Park Service).
The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included. The maps database originated over 30 years ago, but was only recently updated and connected to our main database. We welcome users to tell us if they see incorrect information or other problems with the maps; please use the Contact GVP link at the bottom of the page to send us email.
Title: Tonga Region, Topo of
Publisher: USGS-CCOP/SOPAC S. Pacific Project
Map Type: Bathymetric
There are no samples for Ofu-Olosega in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.
|MIROVA||Middle InfraRed Observation of Volcanic Activity (MIROVA) is a near real time volcanic hot-spot detection system based on the analysis of MODIS (Moderate Resolution Imaging Spectroradiometer) data. In particular, MIROVA uses the Middle InfraRed Radiation (MIR), measured over target volcanoes, in order to detect, locate and measure the heat radiation sourced from volcanic activity.|
|MODVOLC Thermal Alerts||Using infrared satellite Moderate Resolution Imaging Spectroradiometer (MODIS) data, scientists at the Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, developed an automated system called MODVOLC to map thermal hot-spots in near real time. For each MODIS image, the algorithm automatically scans each 1 km pixel within it to check for high-temperature hot-spots. When one is found the date, time, location, and intensity are recorded. MODIS looks at every square km of the Earth every 48 hours, once during the day and once during the night, and the presence of two MODIS sensors in space allows at least four hot-spot observations every two days. Each day updated global maps are compiled to display the locations of all hot spots detected in the previous 24 hours. There is a drop-down list with volcano names which allow users to 'zoom-in' and examine the distribution of hot-spots at a variety of spatial scales.|
|IRIS seismic stations/networks||Incorporated Research Institutions for Seismology (IRIS) Data Services map showing the location of seismic stations from all available networks (permanent or temporary) within a radius of 0.18° (about 20 km at mid-latitudes) from the given location of Ofu-Olosega. Users can customize a variety of filters and options in the left panel. Note that if there are no stations are known the map will default to show the entire world with a "No data matched request" error notice.|
|UNAVCO GPS/GNSS stations||Geodetic Data Services map from UNAVCO showing the location of GPS/GNSS stations from all available networks (permanent or temporary) within a radius of 20 km from the given location of Ofu-Olosega. Users can customize the data search based on station or network names, location, and time window. Requires Adobe Flash Player.|
|DECADE Data||The DECADE portal, still in the developmental stage, serves as an example of the proposed interoperability between The Smithsonian Institution's Global Volcanism Program, the Mapping Gas Emissions (MaGa) Database, and the EarthChem Geochemical Portal. The Deep Earth Carbon Degassing (DECADE) initiative seeks to use new and established technologies to determine accurate global fluxes of volcanic CO2 to the atmosphere, but installing CO2 monitoring networks on 20 of the world's 150 most actively degassing volcanoes. The group uses related laboratory-based studies (direct gas sampling and analysis, melt inclusions) to provide new data for direct degassing of deep earth carbon to the atmosphere.|
Single Volcano View
Temporal Evolution of Unrest
Side by Side Volcanoes
|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.|
|Large Eruptions of Ofu-Olosega||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).|
|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).|