Seismicity of the Cameroon Volcanic Line, 1982–1990

Tabod, Charles T.; Fairhead, J. D.; Stuart, G. W.; Ateba, Bekoa; Nfomou, Ntepe

doi:10.1016/0040-1951(92)90297-j

Cited by 59 publications

(55 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Before 1984, one seismograph was installed in Yaounde (-330 km from the mountain) in 1982. Between 1982 and 1990, seismicity was characterised by discrete events and occasional swarms of about two events every 3 days (Tabod et al 1992). The duration magnitudes were fairly constant at 2.8_+0.1 (Tabod et al 1992) and Modified Mercalli intensity for felt earthquakes ranged from IV to V. All events occurred in the lithospheric mantle, at depths of -30-55 km below the Earth's surface (Ambeh et al 1992).…”

Section: Local Seismicitymentioning

confidence: 99%

“…Between 1982 and 1990, seismicity was characterised by discrete events and occasional swarms of about two events every 3 days (Tabod et al 1992). The duration magnitudes were fairly constant at 2.8_+0.1 (Tabod et al 1992) and Modified Mercalli intensity for felt earthquakes ranged from IV to V. All events occurred in the lithospheric mantle, at depths of -30-55 km below the Earth's surface (Ambeh et al 1992). Widely felt earthquakes on 19 and 26 March 1989 had magnitudes 3.0 and 3.5, respectively, and intensities of IV (Tabod et al 1992;Ateba and Ntepe 1997).…”

Section: Local Seismicitymentioning

confidence: 99%

See 1 more Smart Citation

The 1999 and 2000 eruptions of Mount Cameroon: eruption behaviour and petrochemistry of lava

et al. 2003

View full text Add to dashboard Cite

Mount Cameroon (4,095 m high and with a volume of -1,200 km 3) is one of the most active volcanoes in Africa, having erupted seven times in the last 100 years. This stratovolcano of basanite and hawaiite lavas has an elliptical shape, with over a hundred cones around its flanks and summit region aligned parallel to its NE-SW-trending long axis. The 1999 (28 March-22 April) eruption was restricted to two sites: -2,650 m (site 1) and -1,500 m (site 2). Similarly, in the eruption in 2000 (28 May-19 June), activity occurred at two sites: -4,095 m (site 1) and ~3,300 m (site 2). During both eruptions, the higher vents were more explosive, with strombolian activity, while the lower vents were more effusive. Accordingly, most of the lava (-8x107 m 3 in 1999 and -6x106 m 3 in 2000) was emitted from the lower sites. The 1999-2000 lavas are predominantly basanites with low Ni (5-79 ppm), Cr (40-161 ppm) and mg numbers (34--40). Olivine (Fo77_85 , phenocrysts and Editorial responsibility: J. McPhie

show abstract

Section: Local Seismicitymentioning

confidence: 99%

Section: Local Seismicitymentioning

confidence: 99%

The 1999 and 2000 eruptions of Mount Cameroon: eruption behaviour and petrochemistry of lava

et al. 2003

View full text Add to dashboard Cite

show abstract

“…Both Lakes Nyos and Monoun lie near the Foumban shear zone (Fig. 1), a NE-SW trending fault complex that is seismically active (Tabot et al 1992). Details about the geology of Lake Nyos can be found in Schenker and Dietrich (1986), Lockwood et al (1988) and Freeth and Rex (2000).…”

Section: Regional Contextmentioning

confidence: 97%

Depth of Melt Segregation Below the Nyos Maar-Diatreme Volcano (Cameroon, West Africa): Major-Trace Element Evidence and Their Bearing on the Origin of CO2 in Lake Nyos

Aka

2015

Advances in Volcanology

View full text Add to dashboard Cite

The Nyos maar-diatreme volcano on the Oku Volcanic Group (OVG) in NW Cameroon carries yet the most infamous maar lake in the world because the lake exploded in 1986 releasing CO 2 that killed *1,750 people and over 3,000 livestock. A process of safely getting rid of accumulated gas from the lake started in 2001. Even though *33 % of it has been removed, gas continues to seep into the lake from the mantle, so the lake still poses a thread. Available data on basaltic lava from the maar-diatreme volcano and other volcanoes of the OVG are used here to determine the depth and location where the magmas are produced, and to make inferences on the generation of CO 2 in the Nyos mantle. Fractionation-corrected major element data agree well with experimental data on mantle peridotite and suggest that Lake Nyos magmas formed at pressures of 2-3 GPa in the garnet stability field. This inference is corroborated by trace element models that indicate small degree (1-2 %) partial melting in the presence of residual garnet (2-3 %). The basalts have elevated High Field Strength Element (HFSE) ratios (Zr/Hf = 48.5 ± 1.2 and Ti/Eu = 5,606 ± 224) which cannot be explained by any reasonable fractional crystallization model. A viable mechanism would be melting of a mantle that was previously spiked by percolating carbonatitic melts. It is suggested that small degree partial melting of this metasomatised mantle produces the lavas with super chondritic HFSE ratios, and is generating the CO 2 that seeps into and accumulates in the lake, and which asphyxiated people and animals during the 1986 gas disaster. This finding requires that current efforts to degas Lake

show abstract

“…Seismological studies suggest a hot, low density body in the upper mantle (Dorbath et al, 1986 ;Plomerova et al, 1993 ;Tabod et al, 1992), low-Q materials at different depths in the crust and upper mantle (Bak, 1992) and the crust thins from 33 km south of the uplift to 23 km north of the dome . The Adamawa dome is seismically active and the seismicity is related to movements on faults of the FSZ (Nnange et al, 1985 ;Nnange 1991 ;Tabod et al, 1992).…”

Section: Jm Nnange Et Almentioning

confidence: 99%

“…The Adamawa dome is seismically active and the seismicity is related to movements on faults of the FSZ (Nnange et al, 1985 ;Nnange 1991 ;Tabod et al, 1992). …”

Section: Jm Nnange Et Almentioning

confidence: 99%

Determination of the isostatic compensation mechanism of the region of the Adamawa dome, West Central Africa using the admittance technique of gravity data.

Nnange¹,

Djomani²,

Fairhead³

et al. 2009

African Journal of Science and Technology

View full text Add to dashboard Cite

Seismicity of the Cameroon Volcanic Line, 1982–1990

Cited by 59 publications

References 25 publications

The 1999 and 2000 eruptions of Mount Cameroon: eruption behaviour and petrochemistry of lava

The 1999 and 2000 eruptions of Mount Cameroon: eruption behaviour and petrochemistry of lava

Depth of Melt Segregation Below the Nyos Maar-Diatreme Volcano (Cameroon, West Africa): Major-Trace Element Evidence and Their Bearing on the Origin of CO2 in Lake Nyos

Determination of the isostatic compensation mechanism of the region of the Adamawa dome, West Central Africa using the admittance technique of gravity data.

Contact Info

Product

Resources

About