The Quarterly journal of the Geological Society of London . mplex of Archaean rocks. The presence of the latter can be ex-plained only by the assumption that they have been elevated to theirpresent position by earth-movements of considerable magnitude, orthat the beds of the Cape System have been lowered by trough- 1 Vol. liii (1897) p. 334. ??* D. Sharpe and J. W. Salter, Trans. Geol. Soc. ser. 2, vol. vii (1856) p. 203,and F. Sandberger, Neues Jahrb. 1852, p. 581. 96 DR. F. H. HATCH—GEOLOGY OF THE [Feb. 1898, faulting. The latter assumption is by far the more probable.^But, whether caused by
The Quarterly journal of the Geological Society of London . mplex of Archaean rocks. The presence of the latter can be ex-plained only by the assumption that they have been elevated to theirpresent position by earth-movements of considerable magnitude, orthat the beds of the Cape System have been lowered by trough- 1 Vol. liii (1897) p. 334. ??* D. Sharpe and J. W. Salter, Trans. Geol. Soc. ser. 2, vol. vii (1856) p. 203,and F. Sandberger, Neues Jahrb. 1852, p. 581. 96 DR. F. H. HATCH—GEOLOGY OF THE [Feb. 1898, faulting. The latter assumption is by far the more probable.^But, whether caused by an elevation of the Archaean rocks or by thesinking of the Cape Beds, the relative displacement has had amarked effect on the latter, producing in them all the results ofstrong dynamic influences. Lateral thrusting has turned theWitwatersrand Beds sharply up on edge near their outcrop, andseveral well-marked reversed faults have been observed in thecourse of the development of the mines.^ Pig. 4.—Reversed Fault in the Witivatersrand Mine. ^^^ A^^. Scale of Feet 100 200 300 too Boa A good example of these reversed faults is that which causes adouble outcrop of the Main Reef Series of conglomerates on theproperties of the Witwatersrand and Glenluce Gold Mining Com-panies (see fig. 4), the distance between the two outcrops being400 feet, and the vertical displacement 450 feet. Another fault of 1 Prof. Suess, to whom I sent my map, writes me (Nov. 6th, 1897) :— Your work shows in full clearness the picture of a curved, complex sjncHuesunk into Archaean rocks between faults. ^ It may be noted that these dislocations are caused by strike-faults; nume-rous cross-faults have also been observed, but they produce displacements of anormal type. Yol. 54.] WITWATERSRAND AND OTHER DISTRICTS IN S. TRANSVAAL. 97 the same character, and possibly identical with the fault jnstdescribed, exists in the eastern portion of the Simmer & JackMine, and extends into the Rose Deep. This fault strik
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