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NEW YORK STATE MUSEUM 



A PECULIAR LANDSLIP IN THE HUDSON RIVER 



CLAYS 



BY D. H. NEW LAND 



The glacial and postglacial clays of the Hudson valley when 

 occurring in large bodies on slopes are very prone to subsidence 

 or rlowage and occasionally are precipitated en masse as landslides 

 of notable magnitude. There is record of frequent damage by 

 such disturbances to the cities and towns that occupy the terraces 

 along either bank of the Hudson; Albany and Troy, for example, 

 have suffered repeated loss by the disruption of buildings and en- 

 gineering works founded upon the clays. 1 



The landslip illustrated herewith took place March 26, 1908, at 

 Stockport, Columbia co., a short distance east of the Hudson river. 

 It involved a relatively small area, and the main interest centers 

 around the peculiar form which it exhibited and the explanation 

 of its origin in the light of surrounding conditions. 



In the area south of Stockport creek, below its junction with 

 Claverack creek, there is a terrace lying at about the 100-foot 

 contour, or at a like elevation above the Hudson of which it forms 

 the bank for 'some distance. The terrace has been dissected by 

 small streams that in places have cut deeply into the clays, though 

 it still presents a fairly uniform surface with an abrupt descent to 

 the valley bottoms on the north and west. One of the small streams 

 on the north side leads through a ravine past Stockport ceme- 

 tery to enter Stockport creek opposite Columbiaville. The northern 

 bank of this ravine, which was involved in the slip, rises from 60 

 to 75 feet and is made up of well stratified clays resting upon the 

 Hudson River shale. The shale, however, is not exposed within 

 the ravine, so that the whole thickness of the clays can not be stated. 



The subsidence, as appears from the accompanying illustrations, 

 assumed the form of a block fault. A section of the bank 250 



1 Several landslides are mentioned in Mather's report on the first district 

 (1843). The most notable one occurred at Troy on January 1, 1837, and 

 involved a mass of clay estimated at 200,000 tons which was loosened from 

 the face of a terrace and was precipitated a distance of 800 feet toward the 

 river, sweeping away houses in its course and destroying several lives. 

 By another landslip on March 17, 1859, a building in course of erection for 

 St Peter's College at Troy was demolished. In Albany many small slips 

 and subsidences have occurred, as shown by the displaced or cracked walls 

 of buildings. A recent example was the subsidence of a bank of clay on 

 the north side of Elk street, whereby a whole row of houses was displaced 

 and rendered uninhabitable. 



