14 NEW YORK STATE MUSEUM 



Above the Lockatong beds there occurs a great thickness of 

 soft argillaceous shales and occasional sandstone layers. They 

 are predominantly red in color, though a few purple, green, yellow 

 and black beds are present. Ripple-marks, sun-cracks and rain- 

 drop impressions occur at many horizons, and imprints of leaves, 

 of tree stems, or the stems themselves are frequently found. The 

 numerous reptile and other vertebrate tracks, which have made 

 the Newark beds famous, occur chiefly in this subdivision. The 

 evidence is conclusive that these beds also were deposited in 

 shallow water. 



As these groups of rocks are traced northeastward across New 

 Jersey toward New York, certain important changes in their con- 

 stitution can be noted. These are more marked in the case of 

 the Lockatong and Brunswick groups than of the Stockton beds. 

 The latter occur both beneath and above the trap sheet which 

 forms the Palisades and can be seen in numerous exposures along 

 the shore of the Hudson river. Owing to the influence of the trap 

 sheet, the adjoining beds are generally highly metamorphosed, the 

 most conspicuous change being an alteration to black and purple 

 or dark green shales, quite unlike any beds in the section along 

 the Delaware river. These changes, however, are due entirely to 

 the alteration produced by proximity to the molten mass of the 

 Palisade ridge at the time of its intrusion into the sedimentary 

 beds. 



The Lockatong beds do not occur in the northeastern part of 

 the New Jersey area. Their absence is probably due to the fact 

 that the conditions favoring the deposition of fine grained, hard 

 carbonaceous shale and argillites did not prevail in this region. 

 The facts so far as known apparently show that the black shales 

 and argillites grade into and are represented by red shale and 

 sandstone to the northeast. 



The Brunswick beds, which on the Delaware river are chiefly 

 soft, argillaceous, red shales, increase in coarseness to the north- 

 east, so that in the region adjoining New York this group consists 

 chiefly of sandstones and even conglomerates. Where the Bruns- 

 wick beds are soft shales, the surface is a gently rolling lowland, 



