Perspectivas petrográficas y geoquímicas de la Unidad Azafrán, en la sección Río Blanco – La Esperanza, Baños, Ecuador

Darwn Patricio Condoy Guiracocha; Oswaldo Patricio Pico Carrasco; Jonathan Víctor Albuja Boada; Christian Wladimir Romero Cóndor; Ricardo Vinicio Andrade Terán; Erick Sebastián  Cruz Carrillo; Gabriela Carolina  Andrade Lescano

doi:10.30550/j.agl/2100

Authors

Darwn Patricio Condoy Guiracocha Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador https://orcid.org/0000-0001-5783-8347
Oswaldo Patricio Pico Carrasco Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador https://orcid.org/0009-0006-5389-2390
Jonathan Víctor Albuja Boada Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador https://orcid.org/0009-0001-1736-8392
Christian Wladimir Romero Cóndor Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador https://orcid.org/0000-0001-9271-4323
Ricardo Vinicio Andrade Terán Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador https://orcid.org/0000-0002-7417-8237
Erick Sebastián Cruz Carrillo Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador https://orcid.org/0009-0002-6470-2258
Gabriela Carolina Andrade Lescano Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador https://orcid.org/0009-0003-8919-2490

DOI:

https://doi.org/10.30550/j.agl/2100

Keywords:

Azafrán, Petrography, Geochemistry, Dynamic Metamorphism, Ecuador

Abstract

Previous investigations documented the best exposures of the Azafrán Unit in the Río Blanco–La Esperanza section; however, detailed information regarding its petrography, geochemistry, and the degree and type of metamorphism is lacking. The present study aims to characterize the
lithostratigraphy, petrography, geochemistry, and metamorphic grade of the Azafrán Unit in order to understand its geological and tectonic evolution. The research examines the lithological and metamorphic
variability observed in the field, evaluating its relationship with magmatic processes and tectonic deformation. Through detailed geological mapping, twelve representative samples of the Azafrán Unit were collected. The results indicate that the unit is composed of monzogranites,
schists, and gneisses, with phaneritic and granoblastic textures. Geochemical analyses reveal a high-K calc-alkaline affinity and enrichment in incompatible elements, indicating a magmatic origin associated with subduction processes. Metamorphism is characterized by greenschist facies, with temperature and pressure gradients ranging from 350 °C to
500 °C and from 3 to 8 kbar, respectively. In this context, the findings confirm that the metamorphosed granitoid series of the Azafrán Unit was subjected to dynamic tectono-metamorphic environments, where deformation and magmatism interacted within an active continental
margin framework. The identified structural heterogeneity rules out homogeneous metamorphic episodes and constitutes evidence of spatial and temporal variations in the intensity of tectonic and metamorphic events.

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Author Biographies

Oswaldo Patricio Pico Carrasco, Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador

Patricio Pico, Geological Engineer and Master in Mining with a specialization in Mineral Processing and Extractive Metallurgy, has 10 years of experience in geomorphological photointerpretation, modeling, and geological hazard assessment at the Ecuadorian Space Institute. His work includes geological and mining mapping in porphyry and epithermal deposits, structural, geological, and geochemical analysis, 3D modeling, and diamond drilling core logging at SolGold. He has also conducted regional mapping, geological cartography, review of historical geological maps, and photogeological analysis and interpretation at the Geological and Energy Research Institute of Ecuador. Additionally, he serves as an independent consultant for geotechnical work in civil engineering projects.

Erick Sebastián Cruz Carrillo , Proyecto de Investigación Geológico y Disponibilidad de Ocurrencias Minerales en el Territorio Ecuatoriano. Dirección de Gestión de la Información. Instituto de Investigación Geológico y Energético. Quito. Ecuador

Erick Sebastián Cruz Carrillo obtained his degree as a Geological Engineer in 2020 from the National Polytechnic School of Ecuador. Since 2024, he has been working as a geologist at “Instituto de Investigación Geológico y Energético (IIGE)”, contributing to research projects. He participated in the sampling of active fluvial sediments in southern Ecuador from 2021 to 2023 and was involved in the geological survey of the Sub-Andean Zone and Oriente Basin in 2024. Currently, he works as a geologist in the regional geology area within the Geological Research and Mineral Resource Occurrence Availability Project in Ecuadorian Territory.

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