The plains are located in the central and southern portion, coinciding with the majority of the human settlements; they have a NNE- SSW orientation and are constituted by volcano-sedimentary material from the surrounding sierra and rolling hills .
La llanura se localiza en la porción centro y sur, que coincide con la mayoría de los asentamientos humanos, tiene una orientación NNE- SSW y está constituida por material vulcano-sedimentario procedente de la sierra y lomeríos que la rodean .