18 BULLETIN 61, U. S. DEPARTMENT OF AGEICULTUEE. 



Analyses^ of material from lake beds northeast of Mina. 



Constituents. 



Insoluble residue 



CaO 



MgO 



K.O (total) 



Na20 (total) 



CI 



Sample No. — 



Per ct. 

 14.70 

 44.06 

 .58 

 .24 

 .25 

 .29 



Per ct. 



56.40 



17.24 



.75 



1.12 



1.47 



.18 



Per ct. 



10.00 



45.80 



1.12 



.38 



1.23 



Tr. 



Perct. 



24.70 



38.42 



.40 



.46 



1.28 



.19 



Per ct. 

 69.70 

 4.55 

 2.55 

 1.81 

 2.50 



Per ct. 



79.60 



2.33 



.79 



3.08 



3.00 



.49 



Per ct. 



77.90 



1.95 



.76 



1.91 



5.47 



.33 



Per ct. 

 39.20 

 29.92 



2.05 

 .12 



12 



Per ct. 

 46. 00 

 26.67 

 .54 

 1.46 

 1.54 

 .14 



1 Alkalies determined by Cullen; others determined by Young. 

 All except sample No. 1 contain traces of P; aU contain acid-soluble AI2O3 and FejOa. 



The samples were taken from different beds. My examination failed to show- 

 water-soluble carbonates and sulphates, and I found only traces of water-soluble 

 potash. The principal soluble salt was sodimn chloride. Other analyses of these 

 lake beds have been reported and sodium chloride noted. The rhaterial other than 

 that of a calcareous nature consisted of volcanic glass and tuffaceous particles of a 

 volcanic nature. ]\Iicroscopic examination showed much volcanic glass. The 

 examination also indicated that most of the material, excepting calcium and magne- 

 sium carbonates, was of a wind-blown nature and had been deposited in shallow, 

 brackish lakes in which calcium and magnesium carbonates were being laid down. 



The Quaternary lake beds are of considerably less importance than the Tertiary. 

 They contribute some saline material to the present drainage system, but as these 

 beds are in the main sands and silts vidth little visible saline material, they may be 

 regarded as of minor importance. Russell ' reports lacustra! material containing as 

 much as 1.17 per cent sodium chloride. In tliis connection it should be noted that 

 the material obtained from the 985-foot bore, sunk by the Geological Survey in Car- 

 son Sink through recent and Lahontan formations, failed to show any brines or solu- 

 tions of marked saline content. Pgtrographic examin,ation of Lahontan Lake bed 

 sedimentaries shows comparatively little decomposition of the feldspars, 



ALLUVIAL AND DETRITAL MATERIAL. 



The heterogeneous material constituting the valley fills comprises more than 50 

 per cent of the whole basin area. As this material is in a more or less finely divided 

 condition and is subject to the action of percolating waters, decomposition must be 

 more or less active and a not unimportant amount of salines contributed to the present 

 stream systems through the agency of underground and surface waters. 



SPRINGS. 



As has been shown in a previous chapter, numerous hot springs occur in the basin 

 region. No very complete studies of these have been made, and comparatively few 

 analyses have been reported. In the table which follows, I have summarized the 

 analyses of some 16 such springs. 



Analyses of hot spring waters. 



Constituent. 



A. 



B. 



C. 



D. 



E. 



F. 



CI 



so< 



Per cent. 



58.84 



1.41 



Per cent. 



56.72 



2.87 



Per cent. 



58.79 



.94 



Per cent. 1 

 35.00 1 

 4.58 

 .22 

 5.08 

 8.91 1 

 30.35 

 3.79 1 

 .27 

 .25 ! 

 .01 

 .12 i 

 .01 i 

 11.41 



Per cent. 

 38.79 

 14.25 



Per cent. 

 20.27 



s 





C03... . 



.90 



1.05 



.61 



None. 



Trace. 



3207 





Na 



33. 15 

 3.19 



34.78 

 3.33 



30.38 

 3.76 



31.04 



2.69 



Trace. 



1.23 



.04 



29.78 



K... 



.92 



Li 





Ca 



1.99 

 .24 



.91 

 .17 



4.90 

 .40 



1.18 



Mg 



.04 



As 





AI2O3 







.82 

 .20 



.04 

 1 11.92 





SiOj... 



.28 



.i? 



2 13.62 





solids on evaporation 

 s per 100,000) 





Total 

 (part 



100.00 

 3,0C7 



100.00 

 2,443 



100.00 

 2,330 



100.00 

 285 



100.00 

 249.5 



100.00 

 102.1 









' Quaternary History of Mono Valley, 8th Annual Report, U. S. Geol. Survey, p. 307. 

 » Calculated as SiOj. 



