Locality map and section diagram of Phu Noi Locality. The map of Thailand (a); The location of Phu Noi Locality and the distribution of Phu Kradung Formation, the northeastern region with the outline of Kalasin Province (edit by Kantanat Trakulveerayut) (b); the diagrammatic section of Phu Noi (applied from Chowchuvech et al.31) (c).