GEOLOGICAL SECTION OF NEW JERSEY 357 
coarse quartzite and conglomerate composed of small white-quartz 
pebbles imbedded in a siliceous matrix. Its color is generally steel 
blue, but some beds have a yellowish tinge, and reddish layers occur 
near the top. Layers of black shale a few inches in thickness are 
locally intercalated between thick beds of conglomerate and grit. 
Between this formation and the Martinsburg shale there is a gap 
representing the upper part of the Ordovician and all of the Silurian 
below the Salina of the full New York section, but there is no marked 
divergence of dip and strike where the two formations outcrop in 
proximity, and the actual contact is nowhere exposed in New Jersey. 
The beds overlying the Shawangunk conglomerate are red sand- 
stone and shale, and the transition from the Shawangunk is made 
through a series of alternating red sandstone and gray conglomerate, 
so that the upper limit of the Shawangunk is not sharply defined. 
Its thickness is probably from 1,500 to 1,600 feet. 
So far as known, the formation is barren of fossils in New Jersey, 
but at Otisville, N. Y., a euryterid fauna has been found in the black 
shale intercalated with the conglomerate. In the Otisville section 
this fauna, which elsewhere appears only and briefly at the base of 
the Salina, repeats itself many times through a thickness of 650 feet. 
The Shawangunk conglomerate is followed by 2,500 feet or more 
of shales and limestones also referable to the Salina; hence for this 
region it represents only the lower portion of that group. 
High Falls jormation—Thered sandstone and shale which immedi- 
ately overlie the Shawangunk conglomerate have until recently been 
regarded as the equivalent of the Medina sandstone of New York 
and have been so called, but, for the reasons just cited, it is evident 
that they are much younger than Medina and that they must be 
included in the Salina group. Moreover, they lie some distance 
below a limestone which is correlated with the Cobleskill of the New 
York section. The name High Falls has been applied to the red 
shales that overlie the Shawangunk conglomerate in Ulster County, 
N. Y., and has been adopted for New Jersey in place of Medina, 
which is not applicable. 
The lower beds consist of a hard red quartzitic sandstone, inter- 
calated with some green or gray sandstones and softer red shales 
1 Clarke, op. cit., p. 303. 
