FEATURES OF TRAP EXTRUSIONS .IN NEW JERSEY 303 



and shaley material, is instructive in this connection. Following 

 these bluffs southward about 350 feet we come to the southern side 

 of the same river-valley, as shown in Fig. 2. We find there, as we 





should expect, that while the line of the bank is shown by the same 

 downward sweep of the strata, the succession of deposition is quite 

 different from that shown in Fig. i, indicating a desert stream which 







^"^ V •■ 'v 



Shale.. -.-s ir 



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at times may have spread over the whole width of its course, and again 

 dwindled to a rivulet or become dry. It is noticeable that the trap- 

 sheet above also bends downward at this point, showing that a shallow 

 depression still existed here when the lava stream covered the whole. 



