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sands which were forced usually upward along joint planes 

 in the shale, the injection being similar to that of an 

 igneous dyke. After the injection the sands were firmly 

 cemented by calcium carbonate, precipitated from water 

 circulating through the relatively coarse grained dyke. 

 One important conclusion to be drawn from their occurrence 

 is that movement must have taken place while at least 

 the upper sandstones of the Nanaimo series were in a soft 

 and plastic condition. 



Another feature indicates that movement took place 

 while the sediments of the upper part of the series were in 

 a plastic condition. Even in the coarser, most massive 

 beds, such as thick bedded conglomerates, sudden folds or 

 sharp rolls occur, although the beds may be otherwise 

 only moderately disturbed. These rolls, which are really 

 more of the nature of small displacements or faults, are so 

 pronounced that a bed which has a moderate dip in one 

 direction may turn down at right angles, so that the dip of 

 the down-turned portion is vertical and its strike is at right 

 angles to the strike of the bed as a whole. The largest of 

 these sharp rolls, exposed on the west shore near the 

 northern end of Newcastle island, occurs in a coarse 

 grained, thick-bedded conglomerate, and the width of the 

 down-turned portion is about 150 feet (45 m.). In spite 

 of the magnitude and abruptness of the displacement, 

 there is not the slightest indication of extra jointing, 

 shearing, or slickensiding. Instead the fold has occurred 

 as if the conglomerate were as plastic as wet clay. Hence 

 unless we hypothecate more intense folding than is observed 

 and a much thicker cover, which would induce greater 

 pressure, this type of fold can be explained only by the 

 supposition, that the conglomerates and other sediments 

 which have suffered in the same way, were soft and plastic 

 when the folding took place. 



The Nanaimo series was subjected to strong orogenic 

 movement also, presumably during the post-Eocene deform- 

 ation, the deforming forces apparently having their origin 

 to the northeast, probably below the basin between Van- 

 couver island and the mainland. The series was deformed 

 into broad open folds, complicated by small closed folds 

 and reversed faults, the latter largely restricted to the west- 

 ern boundary of the basin. The axes of folding have a 



