. Annual report. New York State Museum; Science; Science. GEOLOGY OF THE NEW YORK CITY AQUEDUCT 113 Bridge site, at one stage in the glacial history, served as a natural dam and that water was successfully held above it to an elevation of 530 feet and perhaps ClTYOFNEWYORK ~- 440 BOARD OF WATER SUPPLY ASHOMAN /?£S£/?l/0/# OLIVE BRIDGE DAM SITE ... T T .r T» MA#CH/7,/90a. 3QO Section of Site on CentesLine Corrected /o Jon l»09. Fig 16 Location of the Ashokan dam at Olive Bridge site and a geologic \ j cross section. The small dots in the plan indicate exploratory borings. The I section s
. Annual report. New York State Museum; Science; Science. GEOLOGY OF THE NEW YORK CITY AQUEDUCT 113 Bridge site, at one stage in the glacial history, served as a natural dam and that water was successfully held above it to an elevation of 530 feet and perhaps ClTYOFNEWYORK ~- 440 BOARD OF WATER SUPPLY ASHOMAN /?£S£/?l/0/# OLIVE BRIDGE DAM SITE ... T T .r T» MA#CH/7,/90a. 3QO Section of Site on CentesLine Corrected /o Jon l»09. Fig 16 Location of the Ashokan dam at Olive Bridge site and a geologic \ j cross section. The small dots in the plan indicate exploratory borings. The I section shows the rock profile indicating a preglacial channel of the Esopus. " [" ,' The present Esopus flows in a new postglacial-fchannel at a higher elevation. -v The lowest materials in contact with bed rock are heavy stony till, laminated till and stony laminated clays — all good impervious material wherever exposed and tight upon bed rock. Sands and laminated clays are extensively developed immediately northward of the site and streaks of these deposits interlock to a limited extent with the till materials of the site itself, but they do not extend far and die out in wedges among the heavy deposits that characterize the southern slopes of the 'hill forming the northern terminus of the dam. These pervious streaks do not extend at any point con- tinuously through this hill and consequently as a whole the present barrier as it stands is practically impervious. The poorer materials (assorted gravels and sands) characterize the upstream side, and the better, more impervious materials (till and laminated boulder clays) characterize the downstream side of the proposed Olive. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original New York State Museum. Albany : University of the State of New York
Size: 1714px × 1458px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectscience, bookyear1902
