UNIVERSITY OF CALIFORNIA 

 Bulletin of the Department of Geology 



THE 



GEOLOGY OF POINT SAL. 



BY 



Harold W. Fairbanks 

 CONTENTS. 



Introduction 2 



Topography 3 



Outline of the Geology 4 



Pleistocene 6 



Extent and Character 6 



Elevated Beaches 8 



Miocene 9 



Bituminous Shales 9 



Petrography 10 



Chemical Character 11 



Origin of the Shales 13 



Gypsiferous Clays , 15 



Gypsum Deposits 16 



Volcanic Ash 16 



Petrography 17 



Chemical Character 18 



Knoxville Beds 18 



Occurrence 18 



Relation to the Spheroidal Basalt 19 



Augite-Teschenite 19 



Occurrence 19 



Macroscopic Character 20 



Microscopic Petrography 23 



Chemical Character 29 



Petrographic Relations 33 



Basaltic Intrusion in the Knoxville 38 



Occurrence 38 



Microscopic Character 39. 



