104 University of California Publications in Geological Sciences 



Fossils 



All of the fossils recovered in the Verdi basin occur in the upper sandstone- 

 conglomerate member. Owing to extensive alluvial and terrace cover in the low- 

 lands where they occur, and to numerous faults, mappable beds suitable for 

 detailed stratigraphic correlation were not found. For this reason tbe following 

 comments on the stratigraphic occurrences of the fossils are generalized. 



Plants. — The Verdi flora was collected from blue-gray sandstones exposed in a 

 railroad cut on the Southern Pacific Railroad at U.C. Mus. Pal. Locality 102. The 

 site is near the southern margin of section 9, just south of the Truckee River a mile 

 east of Verdi where the Old Verdi Road crosses the first railroad overpass (there 

 are two) south of the river. The plants occur in sandstones exposed in the north- 

 facing railroad cut, extending from the bridge westward for about 150 feet to 

 where the exposure is covered by a clump of chokecherry; and best fossils were 

 secured from the fine-grained sandstones at the west end of the cut. The 28-foot 

 section exposed here is one of coarse, cross-bedded, lenticular andesitic sandstones 

 interbedded with thin diatomaceous lenses and sandy shales, as shown in figure 2 

 on plate 14. At this locality the section is dipping 2° to 3° northwest. About 300 

 yards farther west, across a north-south fault, the dip increases to about 15°. 

 There the section includes thick diatomite along with sandstone, shale, and pebble 

 conglomerate. As nearly as can be judged, the Verdi flora is approximately 1,000 

 to 1,200 feet above the basalt, though it may be less if the river-bluff section along 

 which the section was measured is duplicated by faulting. 



Mammals. — Identifiable mammalian remains have been found at three localities 

 in the Verdi basin; their stratigraphic occurrence is outlined here and their age 

 significance is reviewed in the chapter on age. 



1. The mastodont tooth described by Buwalda (1914) comes from a locality 

 "about three-fourths of a mile southeast of Verdi." Although the exact site can not 

 be pinpointed, the rocks in the area referred to form a northwesterly dipping 

 section of coarse, blue-gray andesitic sandstone, small-pebble conglomerate, sandy 

 shale, and thick diatomite. This part of the section is typical of the middle to upper 

 part of the upper member. As nearly as can be determined, the locality is at least 

 400 to 500 feet above the flora stratigraphically. 



2. A second mastodont tooth, now at the University of Nevada, was discovered in 

 exposures close to Mogul. This site is clearly in the lower part of the upper mem- 

 ber, in yellow-brown Alta-derived coarse sandstones and pebble conglomerates 

 which dip 10° east. According to my observations, it is approximately 400 feet 

 above the basalt, and approximately 600 feet below the flora stratigraphically. 



3. A fragmentary specimen of a Hipparion tooth was collected by Ira LaRivers, 

 of the University of Nevada, at a locality 1 mile north of Mogul, in a section of 

 alternating sandstone, pebble conglomerate, sandy shale, and diatomite. It lies 

 approximately 200 feet above the Mogul mastodont, and about 400 feet below the 

 flora. 



