Levantamiento geológico y estratigráfico para la definición de ambientes sedimentarios en el sector Tierras Blancas, parroquia Susudel, cantón Oña, provincia del Azuay

Abstract

Abstract: This study characterizes the sedimentary paleoenvironments of the Tierras Blancas sector of Susudel, Oña canton, through the topographic, geological, and sedimentological analysis of thirteen outcrops. Detailed stratigraphic columns were constructed, describing lithology, thickness, sedimentary structures, and facies. A 1:8000 scale lithological map was also produced, integrating the surface distribution of diatomites, shales, sandstones, and colluvial deposits. The results show a high-energy lacustrine system dominated by facies of massive and laminated diatomites, laminated and massive shales, and sandstones with fragments of lithic tuffs, indicating a strong volcanic influence on the provenance of the sediments. The lithostratigraphic correlation between outcrops allowed for the definition of a diatomaceous lacustrine succession with cycles of deepening and shallowing, controlled by variations in clastic and volcaniclastic input, as well as by fluctuations in lake level. This allowed for the determination of the spatial distribution and temporal evolution of sedimentary paleoenvironments, providing a geological basis for future resource and risk studies in the area.