196 BRIGHAM—TOPOGRAPHY AND DEPOSITS OF MOHAWK VALLEY. 
deep and locally known as the “ Palisades.” Westernville lies upon a 
terrace 36 feet above the river and about 575 feet above the sea. This 
terrace continues southward toward the Palisades, but less simply than 
the figure suggests. On the west the terrace level swings, like the river, 
past Delta village around to the Palisades, capping a steep eroded bluff 
of sand and gravel 75 feet high and bordering a tract of slightly rolling - 
drift to the westand south. ‘The bowl-shaped depression is about 2 miles 
in diameter, and may have been kept open by stagnant ice, though its 
borders have been rimmed out by the broad meander of the stream. 
There can be little doubt that the preglacial river flowed past the site of 
Delta village into the ‘‘Rome” river; that the passage was blocked by 
a widespreading apron of drift and the river forced to cut a new passage 
- at the Palisades, maintaining for a time a lake in the bow! to the north. 
The rock surface at the top of the. Palisades bluff on the east was well 
swept by the stream before the gorge was begun. 
Rome-Floyd stagnant ice area—Extending from near Rome and the 
Palisades east and southeast to Floyd is a broad and broken terrace which 
seems to have been formed in the presence of lacustrine waters and of 
stagnant ice. Itis 4 to 5 miles long and varies in width from 1 to 2 
miles. Its higher surfaces rise from 520 feet above sea on the riverward — 
side to 600 feet, where it abuts upon the hill slope at the north. Its” 
margin is much broken with some isolated tabular masses, and resembles 
the kame terrace. Its top surfaces as they appear on the atlas sheet, drawn 
to the 20-foot contour line,are much too uniform. The sections all show 
sand and gravel, with inclined and discordant stratification. 
Nine Mile Creek deltaa—Here is one of the most interesting bodies of drift 
in the valley. This is not due to good structure sections, but to its rela- 
tions and surface expression. ‘There can be no doubt that the aqueo- 
glacial discharge from the basin of West Canada creek was chiefly at this 
point. The head of the delta is approximately at Holland Patent, at an 
altitude of 600 feet. Thence the delta extends 53 miles to the Mohawk 
floodplain, where its altitude is 520 feet and its height above the flood- 
plain 100 feet. Itis narrow at Holland Patent, but widens symmetrically 
to 3 miles at its frontal edge, or if, as is probable, a massive bench of drift 
to the southeast is genetically connected with it, the width should be put at 
5 miles. Its surfaces are exceedinely smooth and the mass is beautifully 
dissected to the bottom. The materials are coarser toward the head, and 
at the front consist exclusively, so far as seen, of fine sand, which at two 
points is kept bare by the action of the wind. The drift mantles a floor 
of Trenton limestone and Utica shale, and is of no great thickness, except 
toward the front. To the south and east runs the very massive shelf of 
drift to which reference has been made. It is two miles long and halt a 
