Fig. 19. Map showing distribution of geologic units at the top of the regional saturated zone beneath the Pajarito Plateau. The wells that provided geologic control for this map are indicated by dots using the same color scheme as Fig. 3. The LANL boundary is shown by the green outline and the Pajarito fault zone is shown in blue. The map portrays the dominant rock unit in the upper 15.2 m (50 ft) of the regional saturated zone.