BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 

 Vol. 11, pp. 15-60, pls. 1-8 February 28, 1900 



GEOLOGY OF OAHU 



(Read before the Society August 22, 1899) 



BY C. H. HITCHCOCK 



CONTENTS 



Page 



Introduction 15 



Literature 16 



Hawaiian archipelago 17 



Topography 18 



Kaala range , 19 



Koolau range 20 



Geomorphy 22 



Artesian wells 25 



Coral reef. 29 



Pearl River series . 31 



Rocks at the Pali 31 



Secondary craters 36 



Classification 36 



» Laeloa series 36 



Salt Lake group 38 



Section near Moanalua ... 10 



Makalapa 11 



Tantalus series of craters 11 



Punchbowl or Puowaiua 12 



Diamond head or Leahi 13 



Rocky hill, Kaimuki, and Mauumae 16 



Koko heads 18 



Black ash 49 



Rocks of the basaltic areas 52 



Fossil land shells 51 



Order of events in the geological history of Oahu 55 



Notes on the Tertiary geology of Oahu by W. H. Dall 57 



Introduction 



Oahu is one of the newly annexed Hawaiian islands. It possesses the 

 best harbor in the whole group, and is therefore the most important loca- 

 tion for business, the chief city, Honolulu, containing 40,000 inhabitants 

 and being situated about 2,100 miles southwesterly from San Francisco. 



Ill— Bull. Oeol. Soc. Am., Vol. 11, 1899 (15) 



