POTASH SALTS AND OTHER SALINES IN THE GEEAT BASIN REGION. 7 



In pre-Tertiary formations salines have been reported from tlie upper Silurian, 

 Devonian, Carboniferous, Permian, Triaesic, Jurassic, and Cretaceous. These for- 

 mations, excepting Permian and Cretaceous, are represented to a greater or less 

 extent in the Great Basin. In spite of extensive search on the part of geologists and 

 prospectors, no beds of salines of commercial importance other than gypsum have 

 been discovered. Louderback^ notes the occurrence of gypsum beds in the Triassic 

 at Mound House and Lovelock. Spurr^ notes the occurrence of massive gypsum 

 in lenticular masses in the upper Carboniferous at Cottonwood Springs. Rowe ^ notes 

 shales and gypsum beds overlying the upper Carboniferous in the hills north of Cot- 

 tonwood Springs. A review of the literature leads one to conclude that in the pre- 

 Tertiary formations, excepting the gypsum deposits and minor occurrences of salinif- 

 erous layers, the prospects of finding salines of commercial importance are not good. 



In the Tertiary formations of the basin region saline segregates have been found. 

 The most important occur in Miocene lake beds. Borates, gypsum, and salt are 

 the important minerals that have been noted. Of these, the borates have been 

 commercially exploited and produce the borax supply of the United States. Up 

 to the present there has been little utilization of the gypsum beds. Concerning the 

 salt beds our information is scanty. G. E. Bailey* describes a bed of rock salt 12 

 to 16 feet thick in the Saratoga district, San Bernardino County, Cal. He also 

 describes saline beds occurring on the north slope of Avawatz Mountains in the same 

 county. These beds are, without much doubt, in the Tertiary lake series. So far 

 as known no potash salts, at least in commercial quantities, have been reported from 

 the Tertiary. The Tertiary beds are not looked upon by the writer as of any great 

 importance as a source of supply for potash salts. It must be said, however, that 

 comparatively little systematic work has been done upon them. The Tertiary lake 

 beds, as a whole, have contributed by their erosion a large amount of salt and other 

 salines to their tributary basins. 



The Quaternary lake beds and the lakes accompanying the Quaternary lake basins 

 hold the most important supplies of salines and are the most promising fields for 

 prospecting. Pre-Tertiary and Tertiary formations have supplied the salts which 

 we find as accumulations in the recent drainage basins and lakes. 



Quaternary and recent geologic history has been studied in detail in several of the 

 more important lake basins, and we have in the monographs of Russell and Gilbert 

 ample information of the changes in conditions which have resulted in the formation 

 of saline deposits in these basins. The complete list of the Quaternary lake basins 

 has perhaps not yet been made. From the literature and from personal notes I have 

 compiled the following table: 



List of Quaternary lakes. 



Name. 



Elevation. 



Remarks. 



Boimeville: s 



Present lakes — 



Great Salt Lake 



Utah Lake 



Sevier Lake 



Lahontan: « 



Present lakes 



Honey and Eagle 

 Lakes. 



Pyramid Lake 



Walker Lake 



Winnemucca Lake 



Humboldt Lake 



Carson Sink 



South Carson Lake 



Owens Lake ' 



Searles s 



Panamint 9 



Mono 1*. 



Maximum depth 1,050 feet. 

 Overflowed. 



4,405 to 4,414 

 3,949 



.S, 880 

 4,083 

 3,875 

 3,929 

 3,900 

 3, 916 

 3,569 

 1,700 

 1,046 

 6,426 



326 feet deep. 



886 feet deep; 525 feet above 1882 leveL 

 435 feet deep. 

 530 feet deep. 

 500 feet deep. 

 526 feet deep. 

 510 feet deep. 



Old beach 190 feet above present level. 

 Shore line 600 feet above flat. 

 1,000 feet above vaUey floor are wave-cut terraces. 

 Quaternary area 316 square miles; beach 670 feet above 

 lake level. 



' Bui. No. 223, U. S. Geol. Survey, Gypsum Beds of the United States, p. 118. 



2 U. S. Geological Surveys West of 100th Meridian, vol. 3, p. 166; and Bui. No. 208, U. S. Geol. Survey, 

 Geology of Nevada south of fortieth parallel survey. 

 « Bui. No. 208, U. S. Geol. Survey, Geology of Nevada south of the fortieth parallel, p. 170. 



* Bui. No. 24, California State Mining Bureau, p. 126. 

 » Monograph I, Lake Bonneville. Gilbert. 



* 11th Annual Report, Lake Lahontan. Russell. 

 T Bui. No. 24, Cal. State Mining Bureau. 



« 10th Annual Report, Cal. State Mineralogist. 



* Bui. No. 200, U. S. Geol. Survey. Campbell. 

 " 8th Annual Report, U. S. Geol. Survey. 



