Edifice growth and collapse of the Pliocene Mt. Kenya: Evidence of large scale debris avalanches on a high altitude glaciated volcano

cg.contactJeroen.Schoorl@wur.nlen_US
cg.contributor.centerWageningen University & Research Centre - WURen_US
cg.contributor.centerUniversity of Twente - UT Netherlandsen_US
cg.contributor.centerInternational Crops Research Institute for the Semi-Arid Tropics - ICRISATen_US
cg.contributor.centerVrije Universiteit Amsterdam - VUen_US
cg.contributor.crpCRP on Dryland Systems - DSen_US
cg.contributor.funderNot Applicableen_US
cg.coverage.countryKEen_US
cg.coverage.regionEastern Africaen_US
cg.creator.idClaessens, Lieven: 0000-0003-2961-8990en_US
cg.date.embargo-end-date2018-10-24en_US
cg.identifier.doihttps://dx.doi.org/10.1016/j.gloplacha.2014.10.010en_US
cg.isijournalISI Journalen_US
cg.issn0921-8181en_US
cg.journalGlobal and Planetary Changeen_US
cg.subject.agrovocagricultureen_US
cg.volume123en_US
dc.contributorVeldkamp, Tomen_US
dc.contributorClaessens, Lievenen_US
dc.contributorVan Gorp, Wouteren_US
dc.contributorWijbrans, Janen_US
dc.creatorSchoorl, Jeroen M.en_US
dc.date.accessioned2017-01-05T19:44:26Z
dc.date.available2017-01-05T19:44:26Z
dc.description.abstractThe cyclic growth and destruction of the Late Cenozoic Stratovolcano Mt. Kenya have been reconstructed for its southeastern segment. At least three major debris avalanche deposits have been reconstructed and dated. The oldest deposits indicate an edifice collapse around 4.9 Ma (40Ar/39Ar), followed by a larger event around 4.1 Ma (40Ar/39Ar). The last and best preserved debris avalanche deposit, with still some morphological expression covering the whole 1214 km2 SE sector, occurred around 2.83 Ma (40Ar/39Ar). This very large debris avalanche event must have truncated the whole top of Mt. Kenya. Of the original typical hummocky relief, only local topographical depressions are still best visible and preserved. Using known geometric empirical parameters of the 3 preserved debris-avalanche deposits, the height of the sector collapse is estimated to be in the range of 5100–6500mabove the current height of 1000m a.s.l. near the end lobe of the VDA deposits. This demonstrates that Mt. Kenya attained impressive altitudes during its main activity in the Pliocene, being one of the highest mountains in that time and was most probably covered by an ice cap. Correcting for the known net eastward tilting post eruptive uplift of approximately 500 m of the Mt. Kenya summit, our reconstruction indicates that an at least 5.6 to 7 km a.s.l. high active Mt. Kenya existed in the Pliocene landscape between 5.1 and 2.8 Ma. This volcano must have significantly contributed to regional environmental change, by catching rain on its eastern slopes and projecting a rain shadowtowards the Kenya Rift valley in thewest. The last major edifice collapse event around 2.8 Ma coincides with a major change in regional vegetation. This suggests that the truncating of Mt. Kenya may have caused significant changes in the local climate surrounding Mt. Kenya with possible implications for environmental change in the central Kenya Rift valley, the cradle of hominin evolution.en_US
dc.formatPDFen_US
dc.identifierhttp://oar.icrisat.org/id/eprint/9358en_US
dc.identifierhttps://mel.cgiar.org/reporting/downloadmelspace/hash/vPCHOyrZ/v/64e41b09fe5142d3630ed0295803cafeen_US
dc.identifier.citationJeroen M. Schoorl, Tom Veldkamp, Lieven Claessens, Wouter Van Gorp, Jan Wijbrans. (24/10/2014). Edifice growth and collapse of the Pliocene Mt. Kenya: Evidence of large scale debris avalanches on a high altitude glaciated volcano. Global and Planetary Change, 123, pp. 44-54.en_US
dc.identifier.statusLimited accessen_US
dc.identifier.urihttps://hdl.handle.net/20.500.11766/5354
dc.languageenen_US
dc.publisherElsevieren_US
dc.rightsCC-BY-NC-4.0en_US
dc.sourceGlobal and Planetary Change;123,(2014) Pagination 44,54en_US
dc.subject40ar/39ar geochronologyen_US
dc.subjectlaharen_US
dc.subjectphonoliteen_US
dc.subjectvolcanic debris avalancheen_US
dc.subjectkenya rift valleyen_US
dc.subjectplioceneen_US
dc.subjectmt. kenyaen_US
dc.titleEdifice growth and collapse of the Pliocene Mt. Kenya: Evidence of large scale debris avalanches on a high altitude glaciated volcanoen_US
dc.typeJournal Articleen_US
dcterms.available2014-10-24en_US
dcterms.extent44-54en_US
mel.impact-factor3.548en_US

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