558 HENRY B. KUMMEL 
wick division I am unable to say on account of the complexity 
of structure and their varied lithological character. 
STRUCTURE. 
Folds.—TYhe general structure is that of a faulted monocline, 
the beds of which trend N- 30° 'E., and dip 12° or 157 to the 
northwestward. Examined in more detail the structure is seen 
to depart locally from the monocline. Several broad, gentle 
flexures occur, in addition to a few sharply marked folds in the 
vicinity of the intrusive traps and greater fault lines. A good 
example of the former is seen in the shales of the Hunterdon 
plateau, where the beds are so inclined that their outcropping 
edges describe a great curve parallel on the east and southeast — 
to the escarpment of the plateau. The structure is a shallow 
syncline, whose axis is inclined to the northwest. Low folds 
were found along the valley of the Raritan, particularly in the 
region north of Somerville. From New Brunswick to Bound 
Brook the dip is quite uniformly to the northwestward, averag- 
ing 10°, but to the west the monocline is interrupted by gentle 
flexures and swells which are difficult to trace because of the 
absence of individuality in the layers. The broad outcrop of 
the Brunswick shales in the Raritan valley is due in large part 
to these low folds. 
More definite folds—all synclines—occur (a) near the Sand 
Brook trap sheet southwest of Flemington, (4) the New German- 
town trap sheet, and (c) the Watchung traps whose great cres- 
cent curves are due to the synclinal structure of the inclosing 
shales.t In consequence of this fold the beds which outcrop 
near the crystallines along Mine Brook, northeast of Bedminster 
are at the same horizon as those between the two trap sheets 
back of Plainfield and Bound Brook. 
Several examples of sharp folds occur near Glen Moore south- 
west of Hopewell and not far from the end of Rocky Hill ridge. 
Other instances were noted near the faults. 
The beds of the Stockton and Lockatong divisions are most 
Cook, DARTON, DAVIs, et al. 
