[Annals X. Y. Acau. Sci., Vol. XXIII, pp. 14.j-17(). PI. VII. 27 January, 1914] 



' LOCKATOXG FOEMATIOX OF THE TEIASSIC OF XEW 

 JEESEY AXD PENXSYLVAXIA^ 



By a. C. Hawkins 



{Presented hij title before the Academy, 29 Septeinher, lUUJ) 



COXTEXTS 



Page 



Introduction 145 



History 14<3 



^Distribution and topography 14<> 



Stratigraphy 147 



Columnar sections 149 



Faleontologj' 151 



Petrography and chemistiy 155 



Determinations of iron in the I.ockatong argillites 156 



Origin 158 



Crystal growths in the sediments 163 



Tectonics 166 



Mineralogj' 172 



Commercial aspects 172 



Summary 173 



Bibliography 175 



IXTRODUCTIOX 



The study of a recently exposed zone of mineralization in an argillite 

 quarry at Princeton, Xew Jersey, led the writer to extend his investiga- 

 tions to certain interesting features of the rock formations and general 

 tectonics of the region, a full knowledge of which was found to be essen- 

 tial to the elucidation of the original problem. 



The statements herein made are based largely upon obsen^ations made 

 during personal field work by the writer from 1910 to 1912. These data 

 have been supplemented by additional facts supplied in publications of 

 the State and national geological surveys, and by work in the petro- 

 graphical and chemical laboratories of Princeton University. 



A bibliography of the publications that furnish the most important 

 references is to be found at the close of this paper. 



Grateful acknowledgment is hereby made to those who have in various 

 ways aided in the accomplishment of this work, including members of 



1 Manuscript received by the Editor. 23 September, 1913. (145) 



