472 



WILLIAM HERBERT HOBBS 



of the prevailing and rarer fault series in a manner which is made 

 clear by the diagram of Fig. i. In this figure the shape of the 

 unit orographic block — and of many composite blocks of sev- 

 eral orders as well — is shown by the black and also by the 

 stippled area. Two of the prevailing fault directions, N. =b 1 5° E. 



and N. ±: 34° W. correspond to 

 the longer and the shorter diago- 

 nals respectively of this unit 

 block. The fault direction N.zb 

 33° E., which is the most com- 

 mon of those occurring in the 

 southern Pomperaug area, corre- 

 sponds closely to the longer 

 diagonal of three unit blocks in 

 contact along their longer side. 

 Another of the series of faults 

 characteristic of the same south- 

 ern area and trending N. ± 20° 

 E., corresponds to the longer 



Fig. i.-Diagram to illustrate the diagonal of six unit blocks, tWO 

 relationships existing between the shape composite blocks like those jUSt 

 of the " unit " orographic blocks and the described placed in contact along 

 directions of the fault series. 1 • 1 • 1 t^i 



their longer sides, ihe remain- 

 ing directions of faults observed in the area are respectively the 

 shorter diagonals of composite blocks three units long and two 

 wide, four long and six wide, four long and seven wide, and 

 two long and seven wide ; though clearly in these latter instances, 

 the relationships indicated in the diagram are less significant 

 owing to the more complex nature of the composite blocks of 

 which the fault directions are the diagonals. For a more impor- 

 tant indication of the same relationship, which is observed in the 

 actual composite blocks of the area studied, the reader must be 

 referred to the original report.^ 



For the area in question the conclusion has been drawn that 

 the earth's crust has been here subjected to compressive stresses, 



' Loc. cit. pp. 1 17-120. 



