The LPC is an alkaline magmatic complex related to Miocene Andean magmatism.
The parental magma was generated in a depleted mantle and has an arc signature.
A parental tephritic melt produced a clinopyroxenite and an evolved malignite.
Syenites and trachytes are probably the result of AFC processes.
Textural and compositional changes in some minerals indicate a dynamic environment.