Late Holocene Malpaís de Zacapu (Michoacán, Mexico) andesitic lava flows: rheology and eruption properties based on LiDAR image

Abstract

Few monogenetic eruptions that produced lava flows have occurred in historical times, limiting the observations of their impact on human settlements. However, rheological models based on morphological and petrological datasets can contribute to decipher the eruptive dynamics and durations of ancient eruptions. The Malpaís de Zacapu, a temporal-spatial monogenetic volcano cluster at the western margin of the Zacapu lacustrine basin (Michoacán, Mexico), offers a good opportunity to apply such models because of the availability of a high-resolution LiDAR topography from which detailed morphological data was extracted. The Malpaís de Zacapu comprises late Holocene lava flow fields emplaced in the last 3200 years by four different low magnitude volcanic eruptions: Infiernillo, Malpaís Las Víboras, Capaxtiro, and Malpaís Prieto. Jointly these eruptions produced thick andesitic block lava flows covering an area of 38.3 km 2 with a volume of ~ 4.4 km 3 . The lava viscosities at eruption vents were estimated from petro-textural analyses and range between 10 3 and 10 6 Pa s, while the final flow apparent viscosities, obtained from dimensional analyses, vary from 10 8 to 10 10 Pa s. We estimated the mean effusion rate and lava flow emplacement duration for each flow field. Results revealed that the more viscous flows, Malpaís Las Víboras and Malpaís Prieto, could have been emplaced in less than 3 years, while the more fluid Infiernillo probably took less than 1 year. In stark contrast, the morphologically different and more voluminous Capaxtiro flow field could have been emplaced in ~ 27 years. These findings can help to evaluate the impact that these eruptions had on adjacent pre-Hispanic populations, known to have inhabited the region since at least 3000 years ago.

Petrogenesis of mafic-intermediate magmatism of the Michoacán–Guanajuato volcanic field in Western Mexico. A geochemical review

“…As already stated for felsic rocks (e.g., Sosa-Ceballos et al, 2021), tectonic stresses might define the evolution and final composition of intermediate rocks. We suggest that highsilica intermediate rocks represent magmas that were trapped in compressional zones and hosted by granites for Suhardja et al, 2015;Osorio-Ocampo et al, 2018;Pérez-Osorio et al, 2018;Ramírez and Uribe, 2019;Reyes-Guzmán et al, 2021), to investigate which type of intermediate rock (low-Mg and high-Mg) contain greater contents of quartz and relate their abundance to their relative residence time in the upper crust is a pending task.…”

“…Different authors show that intermediate volcanic rocks from the MGVF (Wilcox, 1954;Luhr and Carmichael, 1985b;Hasenaka and Carmichael, 1987;Kelemen, 1995;Verma and Hasenaka, 2004;Chevrel et al, 2016;Reyes-Guzmán et al, 2021) comprise a mineral assemblage characterized by clinopyroxene, dominantly augite and diopside (Wo 1-48 ; Supplementary Table S2; Figure 2A), orthopyroxene with clinoenstatite composition (En 31-99 ; Supplementary Table S2; Figure 2A), plagioclase with disequilibrium textures and albite-bytownite composition (An 3-83 ; Supplementary Table S3; Figure 2B), and scarce olivine phenocryst (Fo 62-88 ; Figure 2B; Supplementary Table S1; Wilcox, 1954, Luhr andCarmichael, 1985b;Hasenaka and Carmichael, 1987;Verma and Agrawal, 2011;Chevrel et al, 2016).…”

“…Previous studies in the MGVF have focused on its geochemical characterization, geochronology, petrology, and eruptive dynamics (e.g., Luhr and Lazzar, 1985a;Luhr and Carmichael, 1985b;Hasenaka and Carmichael, 1987;Luhr et al, 1989;Cébria et al, 2011;Chevrel et al, 2016;Rasoazanamparany et al, 2016;Larrea et al, 2017Larrea et al, , 2019Losantos et al, 2017;Avellán et al, 2020;Bólos et al, 2020;Bólos et al, 2021;Ramírez-Uribe et al, 2021;Reyes-Guzmán et al, 2021;Sosa-Ceballos et al, 2021). Nevertheless, the petrogenesis and relation of the mafic and intermediate volcanic rocks of the MGVF and their tectonic implication with the TMVB is still a debated topic (e.g., Luhr and Lazzar, 1985a;Luhr and Carmichael, 1985b;Hasenaka and Carmichael, 1987;Luhr et al, 1989;Cébria et al, 2011;Chevrel et al, 2016;Hernández-Bernal et al, 2016;Rasoazanamparany et al, 2016;Losantos et al, 2017;Ramírez-Uribe et al, 2021;Sosa-Ceballos et al, 2021).…”

Las Cabras volcano, Michoacán-Guanajuato Volcanic Field, México: Topographic, climatic, and shallow magmatic controls on scoria cone eruptions

“…Finally, all of the above features are partially covered by young Late-Pleistocene to Holocene volcanoes with pristine morphology that occur all around the basin, but more particularly to its SW, forming a broad WSW-ENE alignment of vents west of Zacapu city (Figure 2). This latter area is of particular interest for assessing volcanic hazards, given the ~77000 inhabitants of the Zacapu municipality (INEGI, 2020;Reyes-Guzmán et al, 2021). It also hosts important archaeological sites of interest for constraining the development of pre-Hispanic civilizations in this formerly densely inhabited region (e.g., Michelet et al, 1989;Migeon, 1998;Arnauld and Faugère-Kalfon, 1998;Darras et al, 2017;Forest et al, 2019;Pereira et al, 2021).…”

“…Andesites are porphyritic and contain up to 10 vol.% of phenocrysts that often show disequilibrium textures such as sieved plagioclases with resorbed margins and quartz with reaction coronas of augite microlites. The most recent eruptions (Mahgoub et al, 2018;Reyes-Guzmán et al, 2021) occurred during the Late Holocene, between 1500 BC and (Siebe et al, 2014). Rectangles in broken lines indicate areas mapped in detail (Alberca de Guadalupe: Kshirsagar et al, 2015;El Caracol: Kshirsagar et al, 2016;W Zacapu: Reyes-Guzmán et al, 2018;Mazcuta near Comanja: Ramírez-Uribe et al, 2019) AD 900, forming closely-spaced viscous flows near to the basin (Malpaís Prieto, El Capaxtiro, Mesa La Víbora, Malpaís Las Víboras, and El Infiernillo).…”