DISTURBED FOSSILIFEROUS ROOKS IN THE VICINITY 

 OF RONDOUT N. Y. 



BY GILBERT VAN IXGEX AND P. EDWIN CLARK 

 With 13 plates 



The present paper describes briefly some of the more import- 

 ant stratigraphic and tectonic features observed by the authors 

 during several years work in the vicinity of the cement mines 

 at Rondout N. Y. It is a statement of progress of investiga- 

 tions now being carried on and is submitted with the object of 

 bringing to the attention of geologists the highly interesting fea- 

 tures of that region. 



Several writers have published short papers on the region, 

 but these have evidently been based on far too hasty examina- 

 tion, with the result that, while the more evident features have 

 been described, numerous far more interesting though often less 

 easily recognized phenomena have escaped attention, and the 

 paleontology has been entirely neglected. 



The particular district described embraces the hill railed the 

 Vlightberg in the city of Rondout, on which are located the 

 quarries and mines of the Newark Lime & Cement Co., and 

 also that wooded range of hills, referred to in this paper as the 

 North hill fronting the Hudson river and extending from the 

 Vlightberg northward to the Terry triangulation station of the 

 United States Geological Survey situated on the hill west of 

 Terry's brickyard, about 1 mile north of Kingston Point. This 

 area, about 1% miles long by % mile wide, has been the scene 

 of quarrying operations during the past 60 years, and the open- 

 ings, which in the Vlightberg are common along the eastern por- 

 tion of the hill, afford unusual opportunities for observation of 

 the interesting and complex tectonic phenomena in which the 

 region abounds. Folds, faults and overthrusts can be seen in 

 almost diagrammatic clearness. Up to the present time almost 

 nothing has been done toward description of the fossil faunas 

 of Ulster counly, and as the Rondout region affords excellent 

 opportunities for collecting fossils from the various members of 

 the Siluric and Lower Devonic formations, a considerable 



