54 



BULLETIN 61, U. S, DEPAKTMENT OF AGEICULTUEE. 



across the central part. The marsh has some of the characteristics of Rhodes Marsh. 

 No chemical data are available, except those published by the United States Geological 

 Survey in the press bulletin noted below.' In this report Gale describes the dis- 

 covery of a mud at depths from 18 to 38 feet, containing a small percentage of soluble 

 salts, and a high content of potash in the soluble salts. The analyses follow: 



Analyses of samples from Columbus Marsh, Nev. 

 [W. B. Hicks, analyst 1 



No. of sample. 



Depth. 



Total 

 soluble 

 salts. 



Percentage of total soluble 

 salts. 





K. 



KsO. 



KCl. 



1 



Feel. 



1 



3 



4i 



9 



12 



18 



27 



30 



33-38 



Per cent. 



17.20 

 9.07 

 8.88 



10.15 

 1.93 

 5.17 

 6.30 

 6.17 

 6.22 



1.67 

 2.55 

 2.48 

 2.95 

 (>) 



16.64 

 20.90 

 13.69 

 17.12 



2.01 

 3.07 

 2.99 

 3.55 

 G) 



20.05 

 25.18 

 16.49 

 20.63 



3.18 



2 



4.85 



3 



4.73 



4 



5.62 



5 



0) 



6 



31.72 



7 



39.83 



8 



26.09 



9 



32.64 







1 Not determined. 



The results are unlike anything as yet reported and their full significance can not 

 be determined without further investigation. The low saline content, 6 per cent, 

 together with the average potassium content, 17.09 per cent (average of results from 

 18 to 38 feet), would give a potassium content of 1 per cent on the original material 

 dried. The conditions very much suggest that in this occurrence we have a sample 

 of the absorption of a residual mother liquor by wind-blown desert material. It is a 

 matter of doubt whether this mud and brine could be, utilized. The removal of a 

 brine from a mud would be attended with greater difficulties than would be the case 

 with the Searles brines. In the latter case the brines are contained in a coarsely 

 crystalline mass and there is comparatively free movement of the brines. In the for- 

 mer case (a more or less compact mud) there would be slow movement of the brines. 

 The most significant thing is not so much the workability of the muds as their high 

 potassium content and the possibility of a larger brine deposit equally rich in potas- 

 sium at depth. The results of further work in this locality will be awaited with 

 interest. Marsh deposits of borax were worked at Columbus, but at present nothing 

 is being done. • These deposits do not show any points of special interest. 



DIXIE VALLEY. 



Dixie Valley, called Osobb, or Salt Valley, in the Fortieth Parallel Survey Report, 

 lies just east of the Sweetwater range in Churchill County, Nev. It was occupied by 

 a shallow lake which at its maximum covered the present valley to a depth of 150 

 feet. The Railroad Valley Co. explored this area for potash salts by a number of 

 bores, some extending to 100 feet in depth. The bores showed in the central de- 

 pression a bed of salt 11 feet thick, mixed with mud, and below this a bed of black 

 mud, 33 feet thick, containing a few crystals of gaylussite. The brine body under- 

 lying the salt contains salines composed of 92 per cent sodium chloride, 4 per cent 

 sodium carbonate, and from traces to 0.5 per cent potash. The saline efflorescences 

 consist of sodium carbonate and sulphate, but no potash. The highest content of 

 potash found was 1 per cent of the soluble salts. 



Through the courtesy of the Railroad Valley Co. and E. E. Free the results of 

 several bores and the chemical examination of the brines from the bores are pre- 

 sented in the following table: 



Record of drill hole No. 1, Dixie Valley. 



[Locatedslightly northeast of the center of sec. 30, T. 23 N., R. 30 E., being the southwest comer of claim 



No. 42.] 



Feet. 



Salt to 1 



Black salty mud 1 to 2 



Salt with some mud 2 to 3.5 



1 Press Bui., U. S. Geol. Survey, Feb. 12, 1913, 



