Estudio geoquímico de capas de carbón de Malacatos, como posible fuente de elementos críticos

Abstract

Abstract: The surveys of stratigraphic columns, chemical and mineralogical analyzes of the samples collected in the field showed low concentrations of REE with respect to the PAAS, NASC and SGR-1b, certain samples exhibited HREE enrichment: such as Eu 1.08 ppm and 1.30 ppm, Tb between 0.77 ppm and 1.4 ppm, Ho between 0.99 ppm and 1.30 ppm, Tm between 0.40 ppm and 1.0 ppm, and Lu between 0.43 ppm and 0.90 ppm, with respect to the PAAS; and values anomalous trace elements such as V (68.00 ppm) in sample S.D.A-06, Ni (18.00 ppm) in S.D.A-10 and U (2.80 ppm) in S.D.B-02. The mineralogical analyzes indicated the presence quartz (10.3% up to 80.3%), heulandite (22.1% up to 69.7%), cristobalite (0.9% up to 34.6%) and tridymite (1.8% to 37.6%), suggesting a matrix rich in siliceous minerals. Furthermore, the presence of minerals such as pyrite (7.4% up to 56%), jarosite (17.8% up to 55.5%) and volborthite (0.7% to 1.9%) indicate the influence of weathering processes and deposition of minerals associated with specific sedimentation environments, such as rich in sulfides or secondary iron and sulfur minerals.