Pablo Dávila-Harris | Instituto Potosino de Investigacion Cientifica y Tecnologica (original) (raw)
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Papers by Pablo Dávila-Harris
Geofísica internacional, Jun 21, 2024
112th Annual GSA Cordilleran Section Meeting, 2016
EGU General Assembly Conference Abstracts, May 1, 2014
Revista Mexicana de Ciencias Geológicas
El complejo volcánico de Ahualulco (CVA), en la región meridional de la Mesa Central de México, c... more El complejo volcánico de Ahualulco (CVA), en la región meridional de la Mesa Central de México, consta de un conjunto de rocas volcánicas cenozoicas que incluye andesitas emplazadas en el Eoceno medio, seguidas de lavas dacíticas y riolíticas, al igual que secuencias piroclásticas félsicas emitidas durante el Oligoceno, algunas de las cuales contienen granate. En este trabajo se ha encontrado que, al menos, un segundo evento andesítico (andesita Petronilas) ocurrió en ese lapso, y que estuvo ligado a la génesis de la ignimbrita Cortes (de composición riolítica), conformando así un volcanismo bimodal “atípico” evidenciado por las relaciones de campo, mineralogía, correlación de los elementos incompatibles Th y Nb y los patrones de las tierras raras. Adicionalmente, se obtuvieron nuevas edades de cristalización de zircón por el método U-Pb para la Riodacita Zapatero (31.7 Ma), la Riolita Los Cuervos (30.8 Ma), la riolita granatífera El Arenal (31.4 Ma) y el pórfido riolítico El Negro ...
Geological Society of America Abstracts with Programs, 2017
Journal of Volcanology and Geothermal Research
Frontiers in Earth Science
Introduction: Volcanic debris avalanches mobilise large volumes and achieve long runouts with hig... more Introduction: Volcanic debris avalanches mobilise large volumes and achieve long runouts with high destructive potential. However, the propagation processes that generate them are not currently explained by theoretical or numerical models, which are unable to represent deposit observations. Evaluation of the dynamics represented in deposits is therefore vital for constraining su ch models. The Abona volcanic debris avalanche deposit is located on the southern flank of the island of Tenerife, Spain. The deposit exhibits universal microfracturing and cataclasis. Fluidal features such as fluidal mixing of lithological units and diffuse boundaries, and mixed matrix are observed throughout the deposit.Methods: Field description including sedimentology and facies identification and the evaluation of their distribution have allowed the generation of a new conceptual model for the propagation dynamics of this volcanic debris avalanche, and potentially others with similar properties. The dep...
Volcanic and Magmatic Studies Group Conference 2020The Ilopango caldera (IC) is a large active vo... more Volcanic and Magmatic Studies Group Conference 2020The Ilopango caldera (IC) is a large active volcano located along the El Salvador Volcanic Arc. Its magmatism is associated to the subduction of the Cocos plate under the Caribbean plate. Despite the surrounding regions being blanketed in thick and widespread pyroclastic deposits, little was known about the number of large eruptions produced by IC, their magnitude and their age. Here we present the results from field mapping, stratigraphic correlation and geochronological analyses, which provide insights into the magnitude and tempo of large explosive eruptions from IC. The results achieved during this investigation are key for future volcanic hazard assessment for the 3 million inhabitants living in the San Salvador Metropolitan area, which is the most populated city in Central America. Based on stratigraphic correlations, geochronologic constraints (40Ar/39Ar and U-Th-Pb ages) and regional tectonic deformation, the complete pyroclastic sequence of IC has been divided into three formations [1]: the Comalapa (1.78 ¿ 1.34 Ma), Altavista (918 - 257 ka) and Tierras Blancas (<57 ka). Each eruption deposit identified was dated by techniques to reconstruct the volcanic history of IC. At least, IC has erupted explosively 13 times since its formation at 1.78 Ma ago. These high number of large eruptions from this volcano-tectonic caldera has been controlled by the El Salvador Fault Zone (ESFZ) [2]. The depth and the high slip-rate of the ESFZ structures assist magma ascent of large volumes of melt, and their eruption produces periodic caldera collapses. The AD 6th century Tierra Blanca Joven (TBJ) was the last explosive eruption of IC, and occurred whilst Mayans populated the region. The TBJ erupted ~30 km3 Dense Rock Equivalent (DRE) of magma [3], and dispersed volcanic ash over Honduras, Guatemala, Nicaragua and the Pacific Ocean. However, the TBJ was significantly smaller than the first eruptions from IC. For example, the pyroclastic density currents (PDC) of the Olocuilta ignimbrite (OI), a caldera forming event at 1.78 Ma, which covers an area of ~3000 km2 with thick pyroclastic density currents (PDC) deposits. Based on the thickness of the deposits of OI (up to 120 m), it is possible that it may have been a supereruption with an erupted volume of ~350 km3 DRE of magma [2]
Earth and Planetary Science Letters, 2020
Journal of Volcanology and Geothermal Research, 2019
Geosphere, 2022
Combined Hf-O isotopic analyses of zircons from tuffs and lavas within the Sierra Madre Occidenta... more Combined Hf-O isotopic analyses of zircons from tuffs and lavas within the Sierra Madre Occidental (SMO) silicic large igneous province are probes of petrogenetic processes in the lower and upper crust. Existing petrogenetic and tectonomagmatic models diverge, having either emphasized significant crustal reworking of hydrated continental lithosphere in an arc above the retreating Farallon slab or significant input of juvenile mantle melts through a slab window into an actively stretching continental lithosphere. New isotopic data are remarkably uniform within and between erupted units across the spatial and temporal extent of the SMO, consistent with homogeneous melt production and evolution. Isotopic values are consistent with enriched mantle magmas (80%) that assimilated Proterozoic paragneisses (~20%) from the lower crust. 18Ozircon values are consistent with fractionation of mafic magma and not with assimilation of hydrothermally altered upper crust, suggesting that the silicic ...
Journal of Volcanology and Geothermal Research, 2019
Bulletin of Volcanology, 2016
Accurate identification of individual volcanic events in the field is crucial for constraining er... more Accurate identification of individual volcanic events in the field is crucial for constraining eruption volumes and calculating recurrence intervals between eruptive episodes. Due to complexities of pyroclastic transport and deposition and intra-unit textural variability, such identification can be challenging. We present a novel method for fingerprinting ignimbrites via trace element chemistry (V, Co, Nb) in biotite by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Using samples from the alkaline magmatic series of Tenerife, we are able to demonstrate (1) clustering of previously characterized units into distinct, homogeneous groups based on V, Co, and Nb concentrations in biotite, despite the presence of extreme variation and zonation in other trace elements (Ba, Sr, Rb) that indicate complex petrogenetic processes, and (2) biotite compositions are similar throughout a deposit and relatively independent of stratigraphic height or juvenile clast texture (crystal-rich vs crystal-poor). Our results show that trace elements in biotite can be used to fingerprint eruptions and correlate geographically separated volcanic deposits, including those preserved in offshore turbidite records.
Journal of Petrology, 2015
Geofísica internacional, Jun 21, 2024
112th Annual GSA Cordilleran Section Meeting, 2016
EGU General Assembly Conference Abstracts, May 1, 2014
Revista Mexicana de Ciencias Geológicas
El complejo volcánico de Ahualulco (CVA), en la región meridional de la Mesa Central de México, c... more El complejo volcánico de Ahualulco (CVA), en la región meridional de la Mesa Central de México, consta de un conjunto de rocas volcánicas cenozoicas que incluye andesitas emplazadas en el Eoceno medio, seguidas de lavas dacíticas y riolíticas, al igual que secuencias piroclásticas félsicas emitidas durante el Oligoceno, algunas de las cuales contienen granate. En este trabajo se ha encontrado que, al menos, un segundo evento andesítico (andesita Petronilas) ocurrió en ese lapso, y que estuvo ligado a la génesis de la ignimbrita Cortes (de composición riolítica), conformando así un volcanismo bimodal “atípico” evidenciado por las relaciones de campo, mineralogía, correlación de los elementos incompatibles Th y Nb y los patrones de las tierras raras. Adicionalmente, se obtuvieron nuevas edades de cristalización de zircón por el método U-Pb para la Riodacita Zapatero (31.7 Ma), la Riolita Los Cuervos (30.8 Ma), la riolita granatífera El Arenal (31.4 Ma) y el pórfido riolítico El Negro ...
Geological Society of America Abstracts with Programs, 2017
Journal of Volcanology and Geothermal Research
Frontiers in Earth Science
Introduction: Volcanic debris avalanches mobilise large volumes and achieve long runouts with hig... more Introduction: Volcanic debris avalanches mobilise large volumes and achieve long runouts with high destructive potential. However, the propagation processes that generate them are not currently explained by theoretical or numerical models, which are unable to represent deposit observations. Evaluation of the dynamics represented in deposits is therefore vital for constraining su ch models. The Abona volcanic debris avalanche deposit is located on the southern flank of the island of Tenerife, Spain. The deposit exhibits universal microfracturing and cataclasis. Fluidal features such as fluidal mixing of lithological units and diffuse boundaries, and mixed matrix are observed throughout the deposit.Methods: Field description including sedimentology and facies identification and the evaluation of their distribution have allowed the generation of a new conceptual model for the propagation dynamics of this volcanic debris avalanche, and potentially others with similar properties. The dep...
Volcanic and Magmatic Studies Group Conference 2020The Ilopango caldera (IC) is a large active vo... more Volcanic and Magmatic Studies Group Conference 2020The Ilopango caldera (IC) is a large active volcano located along the El Salvador Volcanic Arc. Its magmatism is associated to the subduction of the Cocos plate under the Caribbean plate. Despite the surrounding regions being blanketed in thick and widespread pyroclastic deposits, little was known about the number of large eruptions produced by IC, their magnitude and their age. Here we present the results from field mapping, stratigraphic correlation and geochronological analyses, which provide insights into the magnitude and tempo of large explosive eruptions from IC. The results achieved during this investigation are key for future volcanic hazard assessment for the 3 million inhabitants living in the San Salvador Metropolitan area, which is the most populated city in Central America. Based on stratigraphic correlations, geochronologic constraints (40Ar/39Ar and U-Th-Pb ages) and regional tectonic deformation, the complete pyroclastic sequence of IC has been divided into three formations [1]: the Comalapa (1.78 ¿ 1.34 Ma), Altavista (918 - 257 ka) and Tierras Blancas (<57 ka). Each eruption deposit identified was dated by techniques to reconstruct the volcanic history of IC. At least, IC has erupted explosively 13 times since its formation at 1.78 Ma ago. These high number of large eruptions from this volcano-tectonic caldera has been controlled by the El Salvador Fault Zone (ESFZ) [2]. The depth and the high slip-rate of the ESFZ structures assist magma ascent of large volumes of melt, and their eruption produces periodic caldera collapses. The AD 6th century Tierra Blanca Joven (TBJ) was the last explosive eruption of IC, and occurred whilst Mayans populated the region. The TBJ erupted ~30 km3 Dense Rock Equivalent (DRE) of magma [3], and dispersed volcanic ash over Honduras, Guatemala, Nicaragua and the Pacific Ocean. However, the TBJ was significantly smaller than the first eruptions from IC. For example, the pyroclastic density currents (PDC) of the Olocuilta ignimbrite (OI), a caldera forming event at 1.78 Ma, which covers an area of ~3000 km2 with thick pyroclastic density currents (PDC) deposits. Based on the thickness of the deposits of OI (up to 120 m), it is possible that it may have been a supereruption with an erupted volume of ~350 km3 DRE of magma [2]
Earth and Planetary Science Letters, 2020
Journal of Volcanology and Geothermal Research, 2019
Geosphere, 2022
Combined Hf-O isotopic analyses of zircons from tuffs and lavas within the Sierra Madre Occidenta... more Combined Hf-O isotopic analyses of zircons from tuffs and lavas within the Sierra Madre Occidental (SMO) silicic large igneous province are probes of petrogenetic processes in the lower and upper crust. Existing petrogenetic and tectonomagmatic models diverge, having either emphasized significant crustal reworking of hydrated continental lithosphere in an arc above the retreating Farallon slab or significant input of juvenile mantle melts through a slab window into an actively stretching continental lithosphere. New isotopic data are remarkably uniform within and between erupted units across the spatial and temporal extent of the SMO, consistent with homogeneous melt production and evolution. Isotopic values are consistent with enriched mantle magmas (80%) that assimilated Proterozoic paragneisses (~20%) from the lower crust. 18Ozircon values are consistent with fractionation of mafic magma and not with assimilation of hydrothermally altered upper crust, suggesting that the silicic ...
Journal of Volcanology and Geothermal Research, 2019
Bulletin of Volcanology, 2016
Accurate identification of individual volcanic events in the field is crucial for constraining er... more Accurate identification of individual volcanic events in the field is crucial for constraining eruption volumes and calculating recurrence intervals between eruptive episodes. Due to complexities of pyroclastic transport and deposition and intra-unit textural variability, such identification can be challenging. We present a novel method for fingerprinting ignimbrites via trace element chemistry (V, Co, Nb) in biotite by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Using samples from the alkaline magmatic series of Tenerife, we are able to demonstrate (1) clustering of previously characterized units into distinct, homogeneous groups based on V, Co, and Nb concentrations in biotite, despite the presence of extreme variation and zonation in other trace elements (Ba, Sr, Rb) that indicate complex petrogenetic processes, and (2) biotite compositions are similar throughout a deposit and relatively independent of stratigraphic height or juvenile clast texture (crystal-rich vs crystal-poor). Our results show that trace elements in biotite can be used to fingerprint eruptions and correlate geographically separated volcanic deposits, including those preserved in offshore turbidite records.
Journal of Petrology, 2015