%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Ramírez-Uribe, I.
%A Siebe, C.
%A Chevrel, Magdalena Oryaelle
%A Ferres, D.
%A Salinas, S.
%T The late Holocene Nealtican lava-flow field, Popocatépetl volcano, central Mexico : emplacement dynamics and future hazards
%D 2022
%L fdi:010088413
%G ENG
%J Geological Society of American Bulletin
%@ 0016-7606
%K MEXIQUE
%K POPOCATEPETL VOLCAN
%M ISI:000966241900002
%P 2745-2766
%R 10.1130/b36173.1
%U https://www.documentation.ird.fr/hor/fdi:010088413
%> https://www.documentation.ird.fr/intranet/publi/2023-10/010088413.pdf
%V 11-12
%W Horizon (IRD)
%X Popocatepetl, one of the most hazardous volcanoes worldwide, poses significant threats for nearby populations in central Mexico. Therefore, it is important to reconstruct its eruptive history, including estimates of lava-flow emplacement times and their rheological properties. These studies define possible future eruptive scenarios and are necessary to mitigate the risk. Stratigraphic studies of the cal 350-50 B.C. Lorenzo Plinian pumice sequence indicate that effusive activity (Nealtican lava-flow field) occurred shortly after explosive activity, reflecting drastic changes in the eruptive dynamics. It was likely due to the efficient degassing of the magma during the Plinian phase and a decrease of magma ascent and decompression rates. Magma mixing, fractional crystallization, and a minor crust assimilation are the processes controlling the differentiation of the Nealtican lavas. We used lava chemical and mineralogical composition to estimate lava-flow viscosities, and used high-resolution elevation data to estimate emplacement times. Results indicate that lava viscosities of andesites and dacites ranged from 109 to 1012 Pa center dot s and emplacement durations were between similar to 1 and similar to 29 years, depending on the flow unit and morphological method employed. Considering the entire volume of emitted lava (4.2 km(3)) and a mean output rate of similar to 1 m(3)/s to similar to 15 m(3)/s, we estimated that the effusive phase that produced the Nealtican lava-flow field may have lasted similar to 35 years. This eruption had a considerable impact on pre-Hispanic settlements around the volcano, whose population exodus and relocation probably contributed to the rise of important cities in central Mexico, such as Teotihuacan and Cholula.
%$ 064