[Annals N. A*. Acad. Sci., Yol. XIX, No. 11, pp. 247-282, Pll. XXIII, XXIV. 
21 April, 1910] 
AREAL AND STRUCTURAL GEOLOGY OF SOUTHERN MAN¬ 
HATTAN ISLAND 1 
By Charles P. Berkey 
C Read in abstract before the Academy 7 December, 1908.) 
CONTENTS 
Page 
General Features of Local Geology.248 
F ormations.248 
Fordhain Gneiss. 249 
Inwood Limestone.250 
Manhattan Schist. 250 
Glacial Drift.251 
Structural Relations.251 
Folds and Faults.252 
Areal distribution.252 
Areal and Structural Corrections.253 
East River Channel .. 255 
Explorations now in progress and their bearing.256 
Configuration of the Rock Floor.256 
Tabulated Records of Borings in Southern Manhattan Island ...... 257 
Public Service Commission .259 
Borings made in Investigations for Subways . 259 
New A r ork & Long Island Railroad Co. 261 
“ Belmont Tunnel”.261 
Department of Bridges. 262 
Bridge No. 1 — “ Brooklyn Bridge ”.263 
“ “ 2 — “Williamsburg Bridge” or “New East River 
Bridge ”.263 
“ “3 — “ Manhattan Bridge ”.265 
“ “ 4 — “Blackwell’s Island Bridge” or “Queensboro 
Bridge ”.266 
“ “ 5 — “(Projected)”.26S 
1 Published by permission of the New l r ork City Board of Water Supply, under whose 
direction the original study was made. A report covering nearly all of the data now included 
in this paper and all of the essentials of the new interpretation of areal distribution and geologic 
structure was submitted to the Chief Engineer, J. Waldo Smith, Oct. 30, 1908. At that time 
there were no borings in the Lower East Side section, except an occasional one on the water 
front, and the interpretation was based on a very small amount of evidence. Since that time, 
the Board of Water Supply has explored the district, especially along Delancey, Hester and 
Clinton Streets, to a sufficient extent to establish the main features of the revised structure. 
247 
