KLEIN ZWARTBERG AND WITTEBERGS 



391 



quartzites plunge "underground. Farther northward they remain covered 

 beneath the heavy Karroo formations. A view of the northern base of the 

 mountain is given in plate 47, figure 2, showing vertical strata. 



On recrossing the range, when returning by Eooi Nek pass about 10 

 miles farther west, the vertical dips were replaced by overturns, with 

 strong suggestion of overthrnsts. A narrow longitudinal synclinal valley 



Figure 3. — Rough Section of Witteberg Range, looking East. 



The locality is at gorge of Buffels river, south of Laingsburg, Cape Colony. Length, 

 about 10 miles. A patch of Dwyka tillite remains in the synclinal valley. 



south of the range held a patch of Dwyka tillite near the point where we 

 entered it (see figures 2 and 3), thus proving the original extension of at 

 least the Dwyka or basal member of the Karroo system southward into 

 the region of strong folding. The extension of still higher members 

 of the Karroo formations is indicated by the excessive plication which 

 the Witteberg quartzites have suffered hereabout, for this implies that 



Figure 4. — Northern Face of the southern Witteberg Ridge, looking Southwest. 



The foreground is a synclinal valley, followed for a few miles by Buffels river between 

 its upper and lower notches. 



they were buried under a heavy load at the time of their deformation. 

 This is especially true of the ridge that rises next southward from the 

 synclinal valley; it is a severely wrinkled monocline, where the Witte- 

 berg series rises into the air to vault over the great Zwartberg anticline 

 still farther south. The Bokkeveld beds follow this ridge with many 

 minor folds on which a rolling lowland or longitudinal valley has been 

 opened. A view of the northern face of the wrinkled monocline, next 

 east of the Buffels Elver notch, is given in figure 4, looking southwest; 

 this was drawn close to the first L of "Leeuw Kloof poort," in figure 2. 



