REPORT OF THE STATE PALEONTOLOGIST 1901 539 



Saranac river section. The total thickness is not determinable 

 as the outcrops are not continuous and dip faults of con- 

 siderable displacement are known to traverse the region. The 

 minimum thickness is 60 feet which is the hight of the rocky 

 bank on the south side of the Alice Falls fault. 



Below the Alice Falls fault the exposures of the sandstone are 

 practically continuous through the chasm. 



The Keeseville region, as already indicated, is one of tilted 

 fault blocks; the major faults having a direction of about 

 n. 30° e., while the minor faults trend north and south. The 

 close resemblance of the layers throughout the unfossiliferous 

 portion of the sandstone series caused considerable difficulty 

 in the determination of the amount of displacement of the 

 different faults and led to the exclusion, from the total esti- 

 mate of thickness, of those beds the exact position of which 

 could not be satisfactorily established. 



The section of the chasm is through three blocks of sand- 

 stone of which the middle block has been dropped down between 

 the north and the south blocks. 



The north block with a thickness of 50 feet is of uncertain re- 

 lation to the other two, so its thickness has been excluded from 

 the total estimate. 



The south block extending from Devil's Oven to Alice Falls 

 has a thickness of at least 210 feet. The rock of this block is 

 gray and white sandstone in layers of 2 inches to 3 feet thick- 

 ness. Ripple-marks and cross-bedding are common. The only 

 fossils found in the layers of this block were tracks of C 1 i - 

 mactichnites wilsoni which range through 10 feet of 

 ripple-marked layers at a horizon about 90 feet below the top 

 of the block. These layers are exposed at the top of the Bir- 

 mingham fall at the head of the chasm. 



The middle block with the highest beds of this section fur- 

 nished the layers containing brachiopods, trilobites and gastro- 

 pods. The thickness of this block as exposed to view is 245 

 feet. The lowest fossiliferous horizon is at 110 feet from the 

 bottom of the block. This is a sandstone containing pebbles of 



