Wendo Koshe Pumice: The latest Holocene silicic explosive eruption product of the Corbetti Volcanic System (Southern Ethiopia)

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00025798%3A_____%2F16%3A00000016" target="_blank" >RIV/00025798:_____/16:00000016 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.sciencedirect.com/science/article/pii/S037702731500414X" target="_blank" >http://www.sciencedirect.com/science/article/pii/S037702731500414X</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jvolgeores.2015.12.008" target="_blank" >10.1016/j.jvolgeores.2015.12.008</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Wendo Koshe Pumice: The latest Holocene silicic explosive eruption product of the Corbetti Volcanic System (Southern Ethiopia)

Popis výsledku v původním jazyce

The Plinian eruption of the Wendo Koshe crater (Corbetti Caldera) occurred around 396 BC. The pumice lapilli deposit, with a thickness exceeding 10 cm, dispersed over 1000 km2 around the towns of Hawasa and Shashemene. Most of the pumice was deposited by fall-out with minor local pyroclastic density. The calculated volume of preserved pumice fall deposit (1.2 km3), combined with the estimated volume of dispersed fine ash distributed further from the volcano, corresponds to an estimated volume of 0.4 km3 DRE of erupted magma. The age of the pumice eruption (396 BC) was determined by 14C radiometric dating of a paleosoil that developed on previous pyroclastic deposits buried by the pumice. The majority of the post-caldera volcanic products are characterized by a relatively uniformchemical composition (TiO2=0.24–0.27 wt.%, Zr=1300–1600 ppm, ƩREE=920–1150 ppm) without any significant development in composition. Despite the negligible variations in composition of the magmas that erupted during the last 2500 years within the Corbetti, a significant change in composition was documented prior to the 396 BC Wendo Koshe pumice eruption. The caldera stage ignimbrite of Corbetti (TiO2 = 0.34 wt.%, Zr = 500 ppm, ƩREE = 370 ppm) and the early post-caldera obsidians are characterized by a commenditic composition, and the character of the rhyolitic magmas shifted towards pantellerites in the post-caldera stage. The Corbetti ignimbrite is characterized by being more radiogenic (87Sr/86Sr = 0.70678) than the post-caldera obsidians (87Sr/86Sr = 0.7046–0.7047). In contrast to the traceelement concentrations, the early Chabi obsidian does not differ from younger obsidians in isotope composition. Similarly to other silicic volcanic systems of the Main Ethiopian Rift, the rhyolitic magmas of the recently active volcanoes within the Corbetti Volcanic System are most likely produced by extreme fractional crystallization of basaltic melts.

Název v anglickém jazyce

Wendo Koshe Pumice: The latest Holocene silicic explosive eruption product of the Corbetti Volcanic System (Southern Ethiopia)

Popis výsledku anglicky

The Plinian eruption of the Wendo Koshe crater (Corbetti Caldera) occurred around 396 BC. The pumice lapilli deposit, with a thickness exceeding 10 cm, dispersed over 1000 km2 around the towns of Hawasa and Shashemene. Most of the pumice was deposited by fall-out with minor local pyroclastic density. The calculated volume of preserved pumice fall deposit (1.2 km3), combined with the estimated volume of dispersed fine ash distributed further from the volcano, corresponds to an estimated volume of 0.4 km3 DRE of erupted magma. The age of the pumice eruption (396 BC) was determined by 14C radiometric dating of a paleosoil that developed on previous pyroclastic deposits buried by the pumice. The majority of the post-caldera volcanic products are characterized by a relatively uniformchemical composition (TiO2=0.24–0.27 wt.%, Zr=1300–1600 ppm, ƩREE=920–1150 ppm) without any significant development in composition. Despite the negligible variations in composition of the magmas that erupted during the last 2500 years within the Corbetti, a significant change in composition was documented prior to the 396 BC Wendo Koshe pumice eruption. The caldera stage ignimbrite of Corbetti (TiO2 = 0.34 wt.%, Zr = 500 ppm, ƩREE = 370 ppm) and the early post-caldera obsidians are characterized by a commenditic composition, and the character of the rhyolitic magmas shifted towards pantellerites in the post-caldera stage. The Corbetti ignimbrite is characterized by being more radiogenic (87Sr/86Sr = 0.70678) than the post-caldera obsidians (87Sr/86Sr = 0.7046–0.7047). In contrast to the traceelement concentrations, the early Chabi obsidian does not differ from younger obsidians in isotope composition. Similarly to other silicic volcanic systems of the Main Ethiopian Rift, the rhyolitic magmas of the recently active volcanoes within the Corbetti Volcanic System are most likely produced by extreme fractional crystallization of basaltic melts.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

DB - Geologie a mineralogie

OECD FORD obor

—

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Volcanology and Geothermal Research

ISSN

0377-0273

e-ISSN

—

Svazek periodika

310

Číslo periodika v rámci svazku

January

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

13

Strana od-do

159-171

Kód UT WoS článku

000371362300014

EID výsledku v databázi Scopus

—