Longonot

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  • Country
  • Subregion Name
  • Primary Volcano Type
  • Last Known Eruption
  • 0.914°S
  • 36.446°E

  • 2776 m
    9105 ft

  • 222100
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

There are no activity reports for Longonot.



 Available Weekly Reports

There are no Weekly Reports available for Longonot.

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

Start Date Stop Date Eruption Certainty VEI Evidence Activity Area or Unit
1863 ± 5 years Unknown Confirmed 0 Anthropology Northern flank
1330 BCE ± 100 years Unknown Confirmed   Radiocarbon (uncorrected)
7200 BCE ± 100 years Unknown Confirmed   Radiocarbon (uncorrected)

The following references are the sources used for data regarding this volcano. References are linked directly to our volcano data file. 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. Additional discussion of data sources can be found under Volcano Data Criteria.

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.

Rogers N W, Evans P J, Blake S, Scott S C, Hawkesworth C J, 2004. Rates and timescales of fractional crystallization from 238U-230Th-226Ra disequilibria in trachyte lavas from Longonot volcano, Kenya. J Petr, 45: 1747-1776.

Scott S C, 1980. The geology of Longonot volcano, Central Kenya: a question of volumes. Phil Trans Roy Soc London, Ser A, 296: 438-466.

Thompson A O, Dodson R G, 1963. Geology of the Naivasha area. Geol Surv Kenya Rpt, 55: 1-80.

Williams L A J, Macdonald R, Chapman G R, 1984. Late Quaternary caldera volcanoes of the Kenya Rift Valley. J Geophys Res, 89: 8553-8570.

The trachytic Longonot stratovolcano SE of Lake Naivasha in the Gregory Rift valley contains a 8 x 12 km caldera. Formation of the caldera accompanied large explosive eruptions about 21,000 years ago. A large central cone that was constructed within the caldera forms the 2776-m-high summit of the volcano. The younger cone is truncated by a circular, 1.8-km-wide crater. Post-caldera lavas are found on the caldera floor and the volcano's flanks, marking a late stage of effusive eruptions. A well-preserved satellitic cone is located on the NE flank. Masai tradition records a lava flow on the northern flank during the 19th century. Similarly youthful-looking lava flows occur on the SW flank.