PANAMINT RANGE, SEDIMENTARY ROCKS. 
in color from dark gray to black. The dark color is, at least in pan. 
due to carbonaceous matter, since some beds arc fetid and when 
heated exude a tarry substance. The bedding is, as a rule, massive. 
although some slightly argillaceous facies are thin bedded. Cross- 
bedding was noted in several places. Near the top of the seel ion 
occur layers and lenses of black, semitranslucent flint Prom one-half 
inch to 3 inches thick, separated by bands of limestone from 1 to 1 
inches thick. In other beds globular and ellipsoidal flint concrel 
from one-fourth inch to 3 inches in diameter are abundant. A quartz - 
ite layer interbedded with the limestone occurs rather Avell up in the 
formation. The rugged exposures of this white or pinkish-white fine- 
grained quartzite outcrop on the western side of the play a 4 miles 
north of Goldbelt Spring. The bed of quartzite is 100 feet thick and 
has thin bands of limestone interbedded near its base, and especially 
near its top. Four miles south of Tin Mountain Mr. T. C. Spaulding 
noted interbedded in the limestone a 30-foot band of muscovite schist. 
The schist is less metamorphosed than that of Tucki Mountain. 
At one locality the writer collected fragmentary fossils which Mr. 
E. O. Ulrich states include a shell belonging either to Maclurea or 
some related genus and a fragment of a pelecypod. These indicate 
undoubtedly Ordovician and probably Stones River age. Near the 
playa to the north of Goldbelt Spring Messrs. Chapman and Spaul- 
ding collected fossils of which the gasteropods, Mr. Ulrich states, 
remind one of Baltic Ordovician species and indicate a lower Ordo- 
vician horizon. The fossils include a very large Helicotoma-like 
shell; Eccyliopterus sp. undet., of large size and with contiguous 
whorls; Receptaculites sp. nov., obconical, with thick walls and small, 
crowded stolons. Not only in its organic remains, but also in it- 
lithologic character, this limestone resembles the Pogonip limestone 
present in many of the ranges in the area surveyed. It was deposited 
in water of shallow or medium depth, a conclusion indicated by the 
presence here and there of cross-bedding and abundant organic re- 
mains. With the accumulation of the limy sediments the sea bottom 
must have been depressed step by step, an inference drawn from the 
great uniformity and thickness of the limestone. 
Pennsylvanian limestone. — The Pennsylvanian limestone forms a 
narrow band along the east front of the Panamint Range. It is 
separated from the Pogonip limestone to the west by a fault of several 
thousand feet displacement. This limestone, of which probably some 
1,500 feet is exposed, is fine grained and gray or dark gray in color. 
Some of the darker limestone when struck with a hammer gives off a 
fetid odor. Lenses and ellipsoid masses of black flint occur in some 
beds. To the west of the soda-syenite area is a bed 75 feet thick of 
white, fine-grained quartzose sandstone. This sandstone, a- well as 
some beds of limestone, is cross-bedded. 
