Vol. VII] WARING— STRATIGRAPHIC AND FAUNAL RELATIONS 43 



Introduction 



General Statement. — The Chico and most of the Eocene ma- 

 terial on which this paper is based, was collected by a Stanford 

 geologic party, of which the writer was a member, during the 

 summer of 1910. Much of the Tejon material was kindly fur- 

 nished by Messrs. R. B. Moran and J. O. Lewis. 



Since the original manuscript of this report was prepared the 

 writer has had opportunity to visit more territory in the state 

 where the Cretaceous and Eocene are represented. The re- 

 port has been thoroughly revised and all late reports on the 

 subject consulted and incorporated. 



Acknozvledgments. — Thanks are especially due to Dr. J. P. 

 Smith under whose direction this paper was prepared, and to 

 Harold Hannibal for assistance in determination of the faunas. 

 Dr. Roy E. Dickerson has kindly assisted in the revision. 

 Messrs. R. B. Moran and J. O. Lewis have made valuable con- 

 tributions of fossils, without which the relations of the Mar- 

 tinez to the Tejon could not have been embodied in this report. 



Historical Revieiv. — Since the first attempt, made by Dr. T. 

 W. Stanton,^ to clear up the relations of the Cretaceous and 

 Eocene on the Pacific Coast, much has been done towards dif- 

 ferentiating them. The Chico-Tejon beds which were 

 thought by early geologists to be a faunal and stratigraphic 

 unit, have been shown by Dr. Roy E. Dickerson" to consist of 

 three distinct units, separable both faunally and stratigraph- 

 ically. The Martinez formation north of Mt. Diablo is sep- 

 arated from both the Chico and Tejon formations by uncon- 

 formities, and the faunas show strikingly the interruption in 

 sedimentation. Evidence confirms the belief, however, that 

 this unconformity does not exist wherever these formations oc- 

 cur in California. In those parts of central California^ where 

 Chico and Eocene strata occur, with the Martinez lacking, the 

 Tejon rests unconformably on the Chico. 



* Stanton, T. W., The Faunal Relations of the Eocene and Upper Cretaceous on the 

 Pacific Coast, U. S. Geol. Surv. 17th Annual Rept., pt. 1, pp. 1005-1061, 1895-6. 



' Dickerson, R. E., Stratigraphic and Faunal Relations of the Martinez to the Chico 

 and Tejon North of Mount Diablo. Univ. Calif. Publ., Dept. Geol., vol. 6, pp. 171-7, 

 June 28, 1911. 



'Arnold, R., and Anderson, R., Geolojry and Oil Resources of the Coalinga 

 District, U. S. Geol. Surv. Bull. 398, pp. 62-86, 1910. 



