Geomorfología del volcán San Juan, Nayarit, México: Reconstrucción morfológica y sus implicaciones volcanológicas
Geomorphology of San Juan volcano, Nayarit, Mexico: Morphological reconstruction and volcanological implications
Raúl Alvarado-González1, Sergio Salinas2,*, José Irán Bojórquez-Serrano3, Isaac Quijada-Mendoza1, José Juan Zamorano-Orozco1
1 Departamento de Geografía Física, Instituto de Geografía, Universidad Nacional Autónoma de México. Circuito de la Investigación Científica, Ciudad Universitaria, Coyoacán, 04510, CDMX, México.
2 Departamento de Geografía, Facultad de Filosofía y Letras, Universidad Nacional Autónoma de México. Circuito Interior, Ciudad Universitaria, Coyoacán, 04510, CDMX, México.
3 Unidad Académicade Agricultura, Universidad Autónoma de Nayarit. Unidad Académica de Agricultura, Universidad Autónoma de Nayarit. Carretera Tepic-Compostela km 9, Xalisco, 63780, Nayarit, México.
* Autor para correspondencia: (S. Salinas) This email address is being protected from spambots. You need JavaScript enabled to view it.
How to cite this article:
Alvarado-González, R., Salinas, S., Bojórquez-Serrano, J.I., Quijada-Mendoza, I., Zamorano-Orozco, J.J., 2025, Geomorfología del volcán San Juan, Nayarit, México: Reconstrucción morfológica y sus implicaciones volcanológicas: Boletín de la Sociedad Geológica Mexicana, 77(3), A240425. http://dx.doi.org/10.18268/BSGM2025v77n3a240425
Manuscript received:November 28, 2024. Corrected manuscript received: March 23, 2025. Manuscript accepted: April 23, 2025.
ABSTRACT
Through detailed geomorphological mapping, interpretation of satellite images, stratigraphic columns, and interpretation of deposits and their morphologies, a model of geomorphological evolution and eruptive dynamics is proposed for the old and present building of San Juan volcano, Nayarit, Mexico. The geomorphological survey allowed us to recognize eight morphogenetic regions. Detailed mapping of each region consisted of the recognition of genesis, modeling processes, and specific landforms. Morphological and stratigraphic evidence of the collapse of an ancient building called in this study pre-San Juan (>33 ka), which originated a debris avalanche deposit. Subsequently, a dome was emplaced from which pyroclastic block and ash flows were produced. The subsequent Plinian activity (Tepic Pumice) configured the horseshoe morphology of the current crater, as well as the hummocky terrain with mixed and blocky facies, which are part of the eastern outskirts of the San Juan volcano (some of them reached the Tepic plain). The activity ends with the emplacement of a dome from which lava flows descend to the east and north (<14 ka). The geomorphological and stratigraphic analysis highlights the hazard of the San Juan volcano, its eruptive dynamics, and a wide variety of volcanic products (effusive and explosive). This diversity of eruptive styles of the San Juan volcano places the inhabitants of the state capital and surrounding populations (Xalisco, El Refugio, among others) in imminent volcanic hazard.
Keywords: San Juan volcano, geomorphological mapping, debris avalanche deposit, block and ash flows, morphological evolution, eruptive history.