- Info & Contacts
The Global Volcanism Program has no activity reports for La Grille.
The Global Volcanism Program has no Weekly Reports available for La Grille.
The Global Volcanism Program has no Bulletin Reports available for La Grille.
The Global Volcanism Program has no synonyms or subfeatures listed for La Grille.
The Global Volcanism Program is not aware of any Holocene eruptions from La Grille. If this volcano has had large eruptions (VEI >= 4) prior to 10,000 years ago, information might be found on the La Grille page in the LaMEVE (Large Magnitude Explosive Volcanic Eruptions) database, a part of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
There is no Deformation History data available for La Grille.
There is no Emissions History data available for La Grille.
|Grand Comore Island in the Indian Ocean NW of Madagascar is formed by two massive shield volcanoes. The more well-known and historically active Karthala volcano at the southern end of the island has a 3 x 4 km summit caldera. Elongated rift zones extend to the NNW and SE; the lower SE rift zone forms the Massif du Badjini, a peninsula at the SE tip of the island (bottom right). The Holocene La Grille volcano forms the northern part of the island. Youthful lava flows from both volcanoes have reached the coast.
NASA Space Shuttle image STS009-39-2516, 1983 (http://eol.jsc.nasa.gov/).
|Cloud banks drape the flanks of the massive Karthala shield volcano at the southern end of Grand Comore Island. A pyroclastic cone of La Grille, another massive shield volcano that forms the northern part of the island, lies along the coast in the foreground. Karthala contains a 3 x 4 km summit caldera, and elongated rift zones extend to the NNW and SE from the summit of the Hawaiian-style shield. More than twenty eruptions have been recorded at Karthala since the 19th century, but no historical eruptions are known from La Grille volcano.
Copyrighted photo by Steve and Donna O'Meara, 2002.
|Pyroclastic cones drape the eastern flanks of La Grille shield volcano at the northern end of Grand Comore Island (also known as Ngazidja). La Grille contrasts with its larger and more well-known neighbor to the south, Karthala volcano, in its lack of a summit caldera and in its abundance of pyroclastic cones up to 800 m in height. Recent lava flows, some perhaps as young as a few hundred years, have reached the sea from fissures on the lower western, northern, and eastern flanks of La Grille.
Copyrighted photo by Steve and Donna O'Meara, 2002.
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: Comoros, Madagascar, Seychelles
Publisher: DMA Aerospace Center
Country: Comoros, Madagascar
Map Type: Topographic
There are no samples for La Grille in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.
|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 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 La Grille||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).|
|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.|
|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).|