. Annual Reports of the Department of the Interior for the Fiscal Year Ended June 30, 1900--Twenty-First Annual Report of the United States Geological Society. ^ locality where vertical flutings (slickensides)have been observed to characterize the basalt scarps. Distrthutlon of throw over a zone of ixirallel faults.—Although theevidence points to a laige throw in the case of one or two dislocations,yet it seems true that for the area as a whole throw along fault planeshas been small in comparison with the figures usually given for throwalong faults in other areas. As the number of dislocations
. Annual Reports of the Department of the Interior for the Fiscal Year Ended June 30, 1900--Twenty-First Annual Report of the United States Geological Society. ^ locality where vertical flutings (slickensides)have been observed to characterize the basalt scarps. Distrthutlon of throw over a zone of ixirallel faults.—Although theevidence points to a laige throw in the case of one or two dislocations,yet it seems true that for the area as a whole throw along fault planeshas been small in comparison with the figures usually given for throwalong faults in other areas. As the number of dislocations has beenlarge, the displacement along each has been small, although the com-bined effect in any particular zone may be considerable. This is doubt-less explained by a distribution of throw over a series of near-lying. Fig. 33.—Diagram to illustrate crescentic offsetting of outcrops due to progressively increasing tilting of orographic blocks. parallel fault planes. Such distribution of throw may be seen perhapsto the best advantage in the western wall of the basin at about the lati-tude of Pomperaug village. Here the wall of granite and gneiss risesin a series of steps like the ramparts of a fort (idealized in fig. 32).The nearly vertical cliffs which produce these steps trend a little westof north, one having ])een followed for nearly a mile. The two lowersteps of the series are of granite and the upper ones of gneiss, thecontact of the two rocks near the surface being evidently the faultplane its(>lf. The profile of the slope suggests that the throw has beendistriliutod not uniformly over the entire slope, nor yet exclusivel}along the planes which form the largest scarps. l)ut rather in a seriesof narrow zones of parallel faults located near the larger of the presentcliffs. •_M ( IT
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