Fig. 172—Geologic relations of Coast Range, desert deposits, and Maritime Cordillera at Moquegua, Peru. After G. I. Adams; Bol. de Minas del Perú, Vol. 2, No. 4, 1906, p. 20.
Fig. 173—Sketch section to show structural details on the walls of the Majes Valley near Aplao, looking south.
Three other sections may now be examined, one immediately below Cantas, one just above, and one opposite Aplao. The section below Cantas is shown in [173] , and indicates a lower series of red sandstones crossed by vertical faults and unconformably overlain by nearly horizontal conglomerates, sandstones, etc., and the whole faulted again with an inclined fault having a throw of nearly 25°. A white to gray sandstone unconformably overlying the red sandstone is shown interpolated between the lowermost and uppermost series, the only example of its kind, however. No important differences in lithographical character may be noted between these and the beds of the preceding section.
Again just above Cantas on the east side of the valley is a clean section exposing about two thousand feet of strata in a half mile of distance. The foundation rocks are old quartzites and shales in regularly alternating beds. Upon their uneven upper surfaces are several thousand feet of red sandstones and conglomerates, which are both folded and faulted with the underlying quartzites. Above the red sandstones is a thick series of gray sandstones and silts which makes the top of the section and unconformably overlies the earlier series.