Central Island

Photo of this volcano
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  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 3.5°N
  • 36.042°E

  • 550 m
    1804 ft

  • 222010
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

The Global Volcanism Program has no activity reports for Central Island.

The Global Volcanism Program has no Weekly Reports available for Central Island.

The Global Volcanism Program has no Bulletin Reports available for Central Island.

Basic Data

Volcano Number

Last Known Eruption

Elevation

Latitude
Longitude
222010

Unknown - Evidence Credible

550 m / 1804 ft

3.5°N
36.042°E

Volcano Types

Tuff cone(s)
Tuff ring(s)

Rock Types

Major
Basalt / Picro-Basalt
Trachyandesite / Basaltic trachy-andesite
Trachyte / Trachyandesite

Tectonic Setting

Rift zone
Continental crust (> 25 km)

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km
28
28
10,253
216,485

Geological Summary

Central Island, also known as Crocodile Island, occupies the middle of Lake Turkana and is composed of more than a dozen craters and cones, three of which are filled by small lakes. The two largest lakes partially fill craters up to a km wide and about 80 m deep whose floors lie near sea level. The highest point on the dominantly basaltic island reaches 550 m, about 170 m above the lake surface. An E-W-trending chain of small explosion craters cuts the eastern side of the 3-km-wide island. Several small islands to the SE represent partially submerged crater rims, and other cones and lava plugs lie beneath the lake surface near the island. The youngest Central Islands tuffs and lavas may be as young as Holocene (Karson and Curtis, 1992). Fumarolic activity is concentrated along the NE-to-SE rim of the central crater, and sprays of sulfur from the fumaroles were observed by visitors in the 1930s. In 1974 intense emission of molten sulfur and steam clouds were seen from the mainland.

References

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

Bloomer S H, Curtis P C, Karson J A, 1989. Geochemical variation of Quaternary basaltic volcanoes in the Turkana Rift, northern Kenya. J African Earth Sci, 8: 511-532.

Dunkley P N, Smith M, Allen D A, Darling W G, 1993. The geothermal activity and geology of the northern sector of the Kenya Rift Valley. Brit Geol Surv Res Rpt, SC/93/1: 1-185.

Ferguson A J D, Harbott B J, 1982. Geographical, physical and chemical aspects of Lake Turkana. In: Hopson A J (ed) {Lake Turkana: a Report on the Findings of the Lake Turkana Project 1972-75}, London: Rpt Overseas Devel Admin, p 1-107.

Karson J A, Curtis P C, 1994. Axial Quaternary volcanic centers in the Turkana rift, N. Kenya. J African Earth Sci, 18: 15-35.

Richard J J, Neumann van Padang M, 1957. Africa and the Red Sea. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI 4: 1-118.

Wilkinson A F, 1988. Geology of the Allia Bay area. Rpt Mines Geol Dept Kenya, 109: 1-54.

Eruptive History


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


Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
[ 1974 Jul 22 (?) ] [ 1974 Jul 27 ± 1 days ] Uncertain 1   East side of Central Island

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

Crocodile Island | Basso Narok | Fuchich | Gallop | Bor Gheleba | Bass Marle | Boi | Buzz

Craters

Feature Name Feature Type Elevation Latitude Longitude
Bird Nest Island Crater
Broken Island Crater
Bug Island Crater
Chain of Craters Crater
Crocodile Lake Crater
Dry Crater Crater
Flamingo Lake Crater
Tilapia Lake Crater

Photo Gallery


A compound lake-filled crater occupies the SW side of Central Island in the middle of Lake Turkana. A small young crater (left central) cuts the northern rim of the tuff cone, and another large crater whose lake is barely visible lies behind it. These lakes partially fill craters up to a km wide and about 80 m deep whose floors lie near sea level. The small islands (upper right) south of Central Island are part of the volcanic complex, and other cones and lava plugs lie beneath the lake surface. The eastern shore of Lake Turkana is visible on the horizon.

Photo by Martin Smith, 1993 (copyright British Geological Survey, NERC).

Smithsonian Sample Collections Database


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

Affiliated Sites

Large Eruptions of Central Island 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.