PLEISTOCENE GEOLOGY OF NASSAU CO. AND BOROTJGH OF QUEENS 629 



A small exposure of a bed of till also existed in the summer of 

 1900 near Kocky point at the northwestern extremity of the so-called 

 Center island in Oyster bay. The annexed sketches illustrate the 

 varying conditions seen at this 

 locality. In fig. 3 the beds in 

 the bluff west of Rocky point 

 show again the transition from 

 till to stratified beds. A detail 

 of the western part of the sec- 

 tion is given in fig. 4, showing 

 loesslike sands at top, inclosing 

 boulders, beneath which comes 

 a bed of gravelly sand from 6 

 to 10 feet thick, Avith pockets 

 of clay. A gravell}^ till 10 

 feet thick underlies this bed, 

 below which again appear 

 compound gravels and sand. 

 Near the headland underlying 

 blue clays rise up in a knob, 

 with sands cut oS on the east, 

 the whole being overlain uncon- 

 formably by till with boulders up to 2 feet in diameter. At tlie 

 headland on the southwest, the sections shown in fig. 5 and 6 

 exhibit an earthy gravel (as in fig. 6) evidently a phase of the till 

 bed or the till as in fig. 5, resting un conformably on tilted yellow 

 sands, which in turn repose on disturbed clays. 



Fig. 2 Southwestern face of Barker point. 

 A, cross-bedded ferruginous sands; B, the till 

 bed 5 or 6 feet thick, resting unconformably 

 on the sands, and overlain by sands; C, sands; 

 D, surface tiil and boulders, the fine materials 

 being largely rearranged sands 



Fig. 3 Section along the bluflf west of Rocky point, a, clay exposure* B, till; c, sands and 

 gravels; d, partially buried surface boulders 



Above these exposures on the shore the ground rises on the eroded 

 and till-covered slopes of the Columbia. The evidence of uncon- 

 formity between the till bed and the underlying disturbed clays and 

 sands is in sharp contrast with the sections on Hempstead bay and 



