Statistical analysis of geochemistry of stream sediment of the Western Cordillera of the Ecuador (1997-1999) and its correlation with the Cascabel, La Plata and El Domo deposits

Abstract

Geochemical analyses of fluvial sediments from Prodeminca were integrated with geological information, structures, and reports from the Cascabel, La Plata, and Curipamba deposits. Descriptive statistics were performed on 8.522 samples of river sediments from 2º latitude south to 1° north latitude, samples taken between 1997 and 1999. The elements analyzed consisted of As, Co, Cu, Cr, Hg, Ni, Pb, Zn, Au, Mo. Geology was grouped into major lithological units based on their geological environment and age. The results of the statistics were background values and thresholds for element studied, based on its particular and overall lithological population. The associations of geochemical elements were Co-Cr-Ni-Mg-Mn-Y for the domain of Cretaceous Volcanic Sediments and Cu-Zn-Pb-Sb-Zn for the domain of Paleocene-Eocene Volcanic Sediments. The anomalous values of this study coincide with the two metallogenic epochs of the Western Cordillera. The first focused on the Eocene with the Cascabel, El Domo, La Plata and Macuchi deposits which show anomalous Zn values and the second developed in the Miocene with the Llurimagua and Telimbela deposits with anomalous Cu and Mo values respectively.