318 



T. N. Dale — Plicated Cleavage- Foliation. 



interesting ease on the Hardanger fiord in which the cleavage 

 planes traversing a plicated layer have themselves been pli- 

 cated along with the former by secondary pressure. 



After examining many square miles of the Taconic schists, 

 the writer found last summer a case of this kind at West 

 Rutland, Yt. Although the structure is not as extreme as that 

 described by Dr. Reusch it involves identical principles. More- 

 over the evidences of stratification at this locality are so con-, 

 elusive as to separate distinctly the two foliations. 



The exposure is on the south side of a vertical E.-W. joint 

 face in a mass of sericite schist on the west side of the West 

 Rutland valley. Traversing it with a very low westerly dip 

 are several layers 1-3 inches thick and from 1-5 feet apart of 

 calcareous schist which determine at once the direction of the 

 stratification. Across this occurs the prevailing cleavage- 

 foliation of the region, dipping about 30° east. Parallel with 

 these small calcareous beds a highly plicated foliation is seen 

 in places, and there are also indications of a second system of 

 cleavage planes dipping at high angle east, about 80°. (See 

 fig. 1).* In the lower and eastern part of the ledge the pre- 

 vailing cleavage-foliation (I) undulates in gentle folds which 

 measure about one inch in width. 



Figs. 1, 2, from photographs, the compass is 4 inches square. 



See fig. 2 which shows also one of the smaller westerly dip- 

 ping calcareous beds. A specimen taken here from between 

 the calcareous beds would be utterly misleading for it would 

 only show a gently undulating foliation dipping low east 

 crossed by another dipping high east neither of which however 

 is stratification-foliation. 



* In this and the other illustrations the exact relations of the foliation to the 

 horizon are not preserved hut only their mutual relations. 



