The Santa Elena Peninsula, located in the southwest of the Ecuadorian coast, consists of igneous and sedimentary rocks from the Cretaceous to the Quaternary era. The sampled clays originated from the alteration of Andean volcanic ashes found inserted in the clay rocks of the Eocene Medium to Miocene Medium (Ancon Group and, Tosagua and Progreso Formations). Mineralogical analysis (XDR, ATG and ATD), textural analysis (grain size distribution, specific surface and morphological analysis by SEM), and chemical analysis (X-ray fluorescence and CEC), have permitted the selection of four deposits that have iron-montmorillonite as their main clay mineral, in association with kaolinite and traces of mica. Clays of theses deposits have been characterized as calcic bentonites.
Clay; montmorillonite; bentonite; Santa Elena Peninsula; Ancon Group; Tosagua Formation
