Fort Portal

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  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 0.7°N
  • 30.25°E

  • 1615 m
    5297 ft

  • 223001
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

The Global Volcanism Program has no activity reports for Fort Portal.

The Global Volcanism Program has no Weekly Reports available for Fort Portal.

The Global Volcanism Program has no Bulletin Reports available for Fort Portal.

Basic Data

Volcano Number

Last Known Eruption

Elevation

Latitude
Longitude
223001

2120 BCE

1615 m / 5297 ft

0.7°N
30.25°E

Volcano Types

Tuff cone(s)
Maar(s)
Lava dome

Rock Types

Major
Foidite

Tectonic Setting

Rift zone
Continental crust (> 25 km)

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km
242,914
242,914
498,815
4,167,189

Geological Summary

The carbonatite lavas and tuffs of the Fort Portal volcanic field in Uganda, NE of Mount Ruwenzori between Lake Albert and Lake Edward, consists of a group of tuff cones and maars covering an area of about 145 sq km. About 50 volcanic vents, some of which now contain crater lakes, were erupted through basement rocks of Precambrian gneiss in an WSW-ENE-trending area north of the town of Fort Portal. Several additional vents are located in the Kasekere (Rusekere) area to the NE. Radiocarbon dates of about 4700 to 4000 years ago were obtained from ash deposits from the Fort Portal volcanic field. Holmes (1950) noted that Kasensankaranga Crater in the Fort Portal area means "spewer of roasted material," implying an historical age.

References

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography.

Bailey K, Lloyd F, Kearns S, Stoppa F, Eby N, Woolley A, 2005. Melilitite at Fort Portal, Uganda: another dimension to the carbonate volcanism. Lithos, 85: 15-25.

Barker D S, Nixon P H, 1989. High-Ca, low-alkali carbonatite volcanism at Fort Portal, Uganda. Contr Mineral Petr, 103: 166-177.

Holmes A, 1950. Petrogenesis of katungite. Amer Mineral, 35: 772-792.

Holmes A, Harwood H F, 1932. Petrology of the volcanic fields east and south-east of Ruwenzori, Uganda. Quart J Geol Soc London, 88: 370-442.

IAVCEI, 1973-80. Post-Miocene Volcanoes of the World. IAVCEI Data Sheets, Rome: Internatl Assoc Volc Chemistry Earth's Interior..

Nixon P H, Hornung G, 1973. The carbonatite lavas and tuffs near Fort Portal, western Uganda. Overseas Geol Min Res, 41: 168-179.

Vinogradov V I, Krasnov A A, Kuleshov V N, Sulerzhitskiy L D, 1980. C13/C12 and O18/O16 ratios and C14 concentration in carbonatites of the Kaliango volcano (East Africa). Internatl Geol Rev, 22: 51-57.

Eruptive History


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


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
2120 BCE ± 100 years Unknown Confirmed   Radiocarbon (uncorrected)
2750 BCE ± 75 years Unknown Confirmed   Radiocarbon (uncorrected)

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.


Cones

Feature Name Feature Type Elevation Latitude Longitude
Bugumba Tuff cone
Buhara Tuff cone
Bwanika Tuff cone
Hamugoma Tuff cone
Kagode Tuff cone
Kajongo Tuff cone
Kalyango
    Kaliango
Tuff cone
Kasekere
    Rusekere
Tuff cone 1615 m 0° 44' 0" N 30° 23' 0" E
Kigere Tuff cone
Kijongo Kalema Tuff cone
Kijongo Katabyire Tuff cone
Kyeganywa Tuff cone
Mbuzi Tuff cone
Muhoti Tuff cone
Ndeke Tuff cone
Nyabusozi Tuff cone
Rwenkuba Tuff cone
Saka Tuff cone

Domes

Feature Name Feature Type Elevation Latitude Longitude
Makome Dome

Photo Gallery


These grass-covered tuff cones are among the many of the Fort Portal volcanic field in Uganda. The carbonatite lavas and tuffs of the Fort Portal volcanic field were erupted from about 50 volcanic tuff cones and maars, some of which now contain crater lakes. Kasensankaranga Crater in the Fort Portal area means "spewer of roasted material," implying an historical age.

Photo by Nelson Eby (University of Massachusetts).

Smithsonian Sample Collections Database


A listing of samples from the Smithsonian collections will be available soon.

Affiliated Sites

Large Eruptions of Fort Portal 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).
MODVOLC - HIGP MODIS Thermal Alert System 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.
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.