Geochemical and geological prospecting of the Macará area. Analysis of the exploratory potential of the southern border of Ecuador

Abstract

This study presents the main results of the geochemical and geological prospecting carried out from stream sediments and rock samples over Macará area, south of Ecuador, as well as the assessment of the exploration potential based on geological characteristics and mineralization evidences. A global and by geological environments geostatistical analysis was performed for the elements Cu, Pb, Zn, Au, Ag, Hg, As, Sb, Mo, W and Ba from stream sediments and a multi-element analysis employing lithogeochemistry results of mineralized rocks. The resulting anomalies were correlated with lithology, structures, mineralization and hydrothermal alterations, which allowed to locate 16 areas with mineral resources potentiality. The western zone exhibits areas with potential for VMS deposits (Volcanogenic Massive Sulfide) related to lower Cretaceous tholeiitic volcanic rocks, in addition prospective zones for epithermal and porphyry mineralization were defined, probably genetically related to intermediate composition intrusions from Cretaceous as well. Within the eastern zone, element associations revealed prospective areas for epithermal mineralization, probably related to calc-alkaline volcanic sequences of Paleocene-Eocene age. The results obtained, previous studies and by correlation with the reported in the north of Perú, allowed to describe at least three metallogenic epochs for the southern zone of the country, which are analyzed in this study.