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First recorded eruption of Nabro volcano, Eritrea, 2011.

Goitom B, Oppenheimer C, Hammond JO, Grandin R, Barnie T, Donovan A, Ogubazghi G, Yohannes E, Kibrom G, Kendall JM, Carn SA, Fee D, Sealing C, Keir D, Ayele A, Blundy J, Hamlyn J, Wright T, Berhe S - Bull Volcanol (2015)

Bottom Line: It is also relevant in understanding the broader magmatic and tectonic significance of the volcanic massif of which Nabro forms a part and which strikes obliquely to the principal rifting directions in the Red Sea and northern Afar.The whole-rock compositions of the erupted lavas and tephra range from trachybasaltic to trachybasaltic andesite, and crystal-hosted melt inclusions contain up to 3,000 ppm of sulphur by weight.The eruption was preceded by significant seismicity, detected by regional networks of sensors and accompanied by sustained tremor.

View Article: PubMed Central - PubMed

Affiliation: School of Earth Sciences, University of Bristol, Queens Road, Bristol, BS8 1RJ UK ; Department of Earth Sciences, Eritrea Institute of Technology, PO Box 12676, Asmara, Eritrea.

ABSTRACT

We present a synthesis of diverse observations of the first recorded eruption of Nabro volcano, Eritrea, which began on 12 June 2011. While no monitoring of the volcano was in effect at the time, it has been possible to reconstruct the nature and evolution of the eruption through analysis of regional seismological and infrasound data and satellite remote sensing data, supplemented by petrological analysis of erupted products and brief field surveys. The event is notable for the comparative rarity of recorded historical eruptions in the region and of caldera systems in general, for the prodigious quantity of SO2 emitted into the atmosphere and the significant human impacts that ensued notwithstanding the low population density of the Afar region. It is also relevant in understanding the broader magmatic and tectonic significance of the volcanic massif of which Nabro forms a part and which strikes obliquely to the principal rifting directions in the Red Sea and northern Afar. The whole-rock compositions of the erupted lavas and tephra range from trachybasaltic to trachybasaltic andesite, and crystal-hosted melt inclusions contain up to 3,000 ppm of sulphur by weight. The eruption was preceded by significant seismicity, detected by regional networks of sensors and accompanied by sustained tremor. Substantial infrasound was recorded at distances of hundreds to thousands of kilometres from the vent, beginning at the onset of the eruption and continuing for weeks. Analysis of ground deformation suggests the eruption was fed by a shallow, NW-SE-trending dike, which is consistent with field and satellite observations of vent distributions. Despite lack of prior planning and preparedness for volcanic events in the country, rapid coordination of the emergency response mitigated the human costs of the eruption.

No MeSH data available.


Related in: MedlinePlus

Total alkalis versus silica plot for eruptive products from the 2011 eruption
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Fig15: Total alkalis versus silica plot for eruptive products from the 2011 eruption

Mentions: The lava erupted is trachybasaltic to trachybasaltic andesite in composition—between 48–53 wt% SiO2 and 5–7 wt% total alkalis, following a mildly alkali-enriched trend relative to rocks from the axial volcanic ranges in Afar (e.g. Barberi et al. 1972; Fig. 15). Whole-rock MgO contents are low (3–5 wt%). There are abundant phenocrysts of olivine, clinopyroxene, plagioclase and magnetite, with rare ilmenite, chromite and fluorapatite. Microlites of olivine, clinopyroxene, plagioclase and Fe-Ti oxides are present in the ground mass. Some tephra samples are glassy with abundant plagioclase microlites, while others are more crystalline. Phenocrysts show both normal and reverse zoning, indicating a complex plumbing system. This is rare in Afar and may be the result of the presence of thicker crust in the proximity of the Danakil Alps.Fig. 15


First recorded eruption of Nabro volcano, Eritrea, 2011.

Goitom B, Oppenheimer C, Hammond JO, Grandin R, Barnie T, Donovan A, Ogubazghi G, Yohannes E, Kibrom G, Kendall JM, Carn SA, Fee D, Sealing C, Keir D, Ayele A, Blundy J, Hamlyn J, Wright T, Berhe S - Bull Volcanol (2015)

Total alkalis versus silica plot for eruptive products from the 2011 eruption
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4562108&req=5

Fig15: Total alkalis versus silica plot for eruptive products from the 2011 eruption
Mentions: The lava erupted is trachybasaltic to trachybasaltic andesite in composition—between 48–53 wt% SiO2 and 5–7 wt% total alkalis, following a mildly alkali-enriched trend relative to rocks from the axial volcanic ranges in Afar (e.g. Barberi et al. 1972; Fig. 15). Whole-rock MgO contents are low (3–5 wt%). There are abundant phenocrysts of olivine, clinopyroxene, plagioclase and magnetite, with rare ilmenite, chromite and fluorapatite. Microlites of olivine, clinopyroxene, plagioclase and Fe-Ti oxides are present in the ground mass. Some tephra samples are glassy with abundant plagioclase microlites, while others are more crystalline. Phenocrysts show both normal and reverse zoning, indicating a complex plumbing system. This is rare in Afar and may be the result of the presence of thicker crust in the proximity of the Danakil Alps.Fig. 15

Bottom Line: It is also relevant in understanding the broader magmatic and tectonic significance of the volcanic massif of which Nabro forms a part and which strikes obliquely to the principal rifting directions in the Red Sea and northern Afar.The whole-rock compositions of the erupted lavas and tephra range from trachybasaltic to trachybasaltic andesite, and crystal-hosted melt inclusions contain up to 3,000 ppm of sulphur by weight.The eruption was preceded by significant seismicity, detected by regional networks of sensors and accompanied by sustained tremor.

View Article: PubMed Central - PubMed

Affiliation: School of Earth Sciences, University of Bristol, Queens Road, Bristol, BS8 1RJ UK ; Department of Earth Sciences, Eritrea Institute of Technology, PO Box 12676, Asmara, Eritrea.

ABSTRACT

We present a synthesis of diverse observations of the first recorded eruption of Nabro volcano, Eritrea, which began on 12 June 2011. While no monitoring of the volcano was in effect at the time, it has been possible to reconstruct the nature and evolution of the eruption through analysis of regional seismological and infrasound data and satellite remote sensing data, supplemented by petrological analysis of erupted products and brief field surveys. The event is notable for the comparative rarity of recorded historical eruptions in the region and of caldera systems in general, for the prodigious quantity of SO2 emitted into the atmosphere and the significant human impacts that ensued notwithstanding the low population density of the Afar region. It is also relevant in understanding the broader magmatic and tectonic significance of the volcanic massif of which Nabro forms a part and which strikes obliquely to the principal rifting directions in the Red Sea and northern Afar. The whole-rock compositions of the erupted lavas and tephra range from trachybasaltic to trachybasaltic andesite, and crystal-hosted melt inclusions contain up to 3,000 ppm of sulphur by weight. The eruption was preceded by significant seismicity, detected by regional networks of sensors and accompanied by sustained tremor. Substantial infrasound was recorded at distances of hundreds to thousands of kilometres from the vent, beginning at the onset of the eruption and continuing for weeks. Analysis of ground deformation suggests the eruption was fed by a shallow, NW-SE-trending dike, which is consistent with field and satellite observations of vent distributions. Despite lack of prior planning and preparedness for volcanic events in the country, rapid coordination of the emergency response mitigated the human costs of the eruption.

No MeSH data available.


Related in: MedlinePlus