542 LAE fOOKINALERORAGIZOLOG Ye 
deposits on the hills a mile and a half south of Morristown were 
clearly formed by westward moving currents. 
Three particularly favorable classes of localities for the 
deposition of the shore gravels can be made out. These are (a) 
in the shallow, narrow straits between islands, the numerous 
deposits along Long Hill being the most marked examples; (0) 
at the ends of the islands or peninsulas where the shore currents 
(1) kept their course as the island was passed, spits being the 
result, the spit near New Providence being a good example; or 
(2) where the shore currents lost their velocity by spreading, in 
which event terraces were formed, the terrace just north of Lyons 
being an example; (c) at the heads of small converging bays, 
the terraces west of Basking Ridge and east of Bernardsville 
being good examples. 
2. On the outer face of the moraine.—In addition to the con- 
structural shore features already described, there are still others 
in the extra-morainic part of the basin which testify in no doubt- 
ful way to the former existence of Lake Passaic. The outer 
face of the terminal moraine, in so far as it lies in the lake basin, is 
bordered by a subaqueous overwash plain* of goodly proportions. 
The special characteristics of deltas and subaqueous overwash 
plains are flat tops, sloping gently from the head to the front, a 
steep front slope (indicated by hachures on the map), a lobate 
margin with deep re-entrant angles and projecting cusps, and a 
tripartite structure, as seen in vertical section. This structure 
consists of (a) nearly horizontal beds at the top, underlain (6) by 
beds dipping steeply towards the front, and these in turn rest 
upon (c) horizontal or nearly horizontal layers of fine material. 
All these features are illustrated by the plains bordering the 
moraine on its outer face. Thus near West Summit there are 
three prominent marginal lobes on the subaqueous overwash 
plain. West of Madison, the flat top of the plain is a third of a 
mile wide, with a fall of about ten feet in this distance, whereas 
its steep front falls off 60 feet in 100 to 200 yards. Southwest 
t An overwash plain made in standing water. See Annual Report of the State 
Geologist of New Jersey, 1892, p. 41. 
