GREAT FAULT ZONE OF THE SIERRA NEVADA 593 



SOME PECULIARITIES OF ROCK WEATHERING AND SOIL FORMATION IN THE 



ARID REGION 



BY E. W. HILOARD 



GEOLOGY OF THE MINERAL KING BELT 

 BY A. KNOPF AND P. THELEN * 



Published as Bulletin of the Department of Geology, University of Cal- 

 ifornia, volume 4, number 12. 



The Section then adjourned till next morning. 



Session of the Cordillekan Section, Saturday, December 31 



The Section was called to order at 10 a m, Professor E. W. Hilgard in 

 the chair. 



The following papers were read and discussed : 



A DETAIL OF THE GREAT FAULT ZONE OF THE SIERRA NEVADA 

 BY JOHN A. REID * 



[Abstract] 



The writer has been led to this subject by his study of the contact raetamorphism 

 of the granite and slate on the east flank of the Sierra. The particular locality 

 described in this paper is just west of Franktown, in Washoe county, Nevada. 

 The rocks, following Turner, are: (1) the basement complex of granite intrusive 

 in Jurassic (?) slate; and (2) a superjacent series, of volcanics (rhyolite and ande- 

 site) with the gravels of a Tertiary river channel which runs approximately north- 

 east-southwest. A longitudinal north-south fault valley, called Little valley, with 

 almost ideal cross-section, exists here about 1,400 feet above the floor of Washoe 

 valley. From the lower valley the first fault scarp rises 1,500 feet, the crest being 

 the eastern limit of Little valley. On the west the second scarp rises unbroken 

 for 2,000 feet to the crest of the range. The two faults are of different ages, shown 

 by the physiographic features, the lower being the older. East and west faulting 

 also occurs, tending to shift both north-south faults eastward, as well as to make 

 the faulting multiple. Small hanging fault blocks, allied to the "kernbuts" of 

 Professor Lawson, are very noticeable on the upper scarp to the north. The river 

 gravels, being on a basement broken by more complex faulting, show well the 

 character of the movements — in the main a north-south series of normal faults of 

 at least two ages. 



CERTAIN FORMATIONS OF SOUTHWESTERN OREGON 

 BY GEORGE D. LOl'DERBACK 



Published in the Journal of Geology, volume 13, number 6, 1905, pp. 

 514-555. 



♦Introduced by Andrew C. Lawson. 



