Unraveling the tectonics of the scenery from the Cayo Formation Puerto Cayo, Ecuador

Abstract

The aim of the study was to conduct a structural analysis of outcrops from Upper Cretaceous Cayo Formation, south of Puerto Cayo, Manabi Province at the unconformity boundary with the San Mateo Formation (Late Eocene). Due to the lack of a seismometer network spread along the central part of the Ecuadorian active margin, the kinematic analysis of fault planes around Puerto Cayo has been undertaken to understand regional tectonics. The lithology of the outcrops was described and split into three sections. On the basis of the modal composition, samples were classified as Litharenite and Feldspathic Litharenite and Olivine Basalt. Statistical analysis by contour plot in Section One with 39 samples determined a maximum density of strike 161° and dip 40° on normal faults (Nx) and reverse faults (Ix). The main orientation resulted in: strike 84° for Section One and 231° for Section Two with moderate dip between 40° and 32° with rake between 51° and 58°, respectively.