54 NEW YORK STATE MUSEUM 



The Glen-Riparius fault. This fault, whose length is some 8 

 or 9 miles, is clearly the longest one lying wholly within the quad- 

 rangle. It is topographically very plainly marked, a whole line of 

 low mountain peaks forming the crest of the scarp. This great 

 fault block shows a very distinct downtilt toward the east which 

 accounts for the peculiar drainage condition because no considerable 

 streams enter the Hudson river from the east along the line of the 

 fault but, instead, the streams all drain from the crest of the scarp 

 down the eastward slope and into the Friends and Loon lake 

 basins. The Hudson river itself has had its course determined 

 along the base of the scarp. A displacement of from 300 to 600 

 feet is commonly shown. 



Gage-Stockton mountain fault. As shown on the map by the 

 heavy broken line, a prominent fault is thought to extend along the 

 eastern bases of Mill, Stockton, and Gage mountains and south- 

 ward to The Glen. The principal evidences for faulting here are 

 the arrangement of the high, steep mountains along a regular line 

 and the long, smooth contact between the areas of Grenville and 

 mixed gneisses and the igneous rocks. The usual tilted character 

 of the fault blocks is here not shown. Shear zones were not noted 

 though this is of little significance because exposures on the line of 

 the fault are very scarce. The displacement of this fault appears 

 to be as much as 800 or 1000 feet. 



H this fault is actually present, then the large wedge of Grenville 

 and mixed gneisses in the valley bottom is of the nature of a 

 through fault block. 



Oven-Mill mountain faults. These faults are most likely parts 

 of the same line of fracture, though the connection has not been 

 positively traced. In each case Grenville (chiefly limestone) dips 

 eastward and directly against the base of the mountain. The Oven 

 mountain fault scarp, which rises nearly 900 feet and is very steep 

 to almost precipitous, is an impressive sight as viewed from the 

 west. An eastward downtilt of the block is fairly well shown. The 

 Mill mountain scarp is not so steep but rises to a height of over 

 700 feet. Because of the much weaker Grenville between the two 

 mountains, no distinct fault scarp is there present. 



North Creek fault and branch. This prominent fault strikes 

 north-northeast by south-southwest and passes through the village 

 of North Creek. Northward from the village it is very clearly 

 traceable as a topographic feature for at least 10 or 12 miles and 

 well into the Schroon lake quadrangle along the west side of the 



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