El Toro volcanic field
Part of a field of monogenetic volcanoes associated with subduction of the Nazca Plate beneath the South American Plate , it is constructed from three main cones and an additional lava flow . 
<triplet> Nazca Plate <subj> South American Plate <obj> shares border with <triplet> South American Plate <subj> Nazca Plate <obj> shares border with