BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 

 Vol. 6, pp. 241-262 March 21, 1895 



CRYSTALLINE LIMESTONES, OPHICALCITES AND ASSOCI- 

 ATED SCHISTS OF THE EASTERN ADIRONDACKS* 



BY J. F. KEMP 



(Re(((I hffnre the Society, December 28, 1894) 

 CONTENTS 



Page 



Synopsis of aiitlior's previous investitrations 241 



Scope of the paper 242 



Geographic distril)ution of the rocks 242 



Previous and contemporaneous work in the region 243 



The Hmestones of the region 245 



General distribution 245 



Mode of occurrence and associated rocks 245 



The Hmestones of Essex county 246 



Location, extent, relations and mineral constituents 246 



The Port Henry type locality 249 



General description 249 



Cross-sections 249 



Petrography and mineralogy 252 



The limestone 252 



The ophicalcites 253 



The hornblendic and other schists and gneisses 254 



The graphitic mica-schist 255 



The gneiss 255 



The Keene type locality ' 256 



General descrij)tion 256 



Cross-section 257 



Petrography and mineralogy 257 



The granulite 257 



The limestone 258 



Tiie calcite veins 259 



Genetic considerations 261 



Synop.sis of Author's previous Investigations. 



At tlie Boston mectin*; of the Geological Society a year ago the writer 

 presented a sketch of the gabbros which are so plentiful)}^ developed in 



f •The field-work on whioli this paper Is baseci Wivs done at different times witii the ntippurt of 

 Professor James Hall, Dr F. J. H. Merrill and the trustees of Columbia College. The detailed re- 

 ports on the areal neoloj^y, with township maps, have been submitted to the two Kontlemen first 

 named an«l permission has been kindly given for this gcnorel use of the materials. 



XXXIV-Bt'LU Geol. See. Am.. Vor,. 0. 18!i4. (241) 



