56 BULLETIN 61, U. S. DEPARTMENT OF AGEICULTURE. 



Analyses of brines from drilled holes — Continued. 





Depth. 



Conventional combinations, grams per 100 c. c. 



Total 

 solids on 

 evapora- 

 tion, 

 grams per 

 100 c. e. 



KjO, per 



Sample. 



NaCl. 



Na2S04. 



NasCOs. 



KCl. 



Total by 

 addition. 



cent of 

 total 

 solids. 



Hole No. 2: 



60 



Feet. 

 38 

 55 

 67 

 78 

 85 



91.5 

 94.5 



1.3 

 2.5 

 5.5 



11 



14.5 



25 



35 



45 



55 



63 



71 













33.24 

 36.29 

 35.66 

 36.47 

 34.34 

 36.02 

 37.16 



34.99 

 34.81 

 35.00 

 35.60 

 33.92 

 35.79 

 34.65 

 35.30 

 35.77 

 35.01 

 28.70 



33 



61 



28.02 



4.69 



3.25 



0.31 



36.27 



54 



62 



50 



63 













.50 



64 













.51 



65 













57 



66 



27.79 



4.56 



3.53 



.33 



36.21 



.56 



Hole No. 3: 



67 



.28 



68 



28.99 



3.65 



1.77 



.15 



34.56 



.27 



69 



.27 



70 













.25 



71 













.25 



72 













.23 



73 













.19 



74 



28.42 



4.68 



2.21 



.16 



35.47. 



.29 



75 



.35 



76 













.30 



77 













.25 

















Average 



26.92 



4.34 



3.12 



.28 



34.67 



34.96 



.40 









The section shown by the borings indicates very much the same conditions and 

 history as were described in the Silver Peak Marsh. We have here the case of a shal- 

 low lake passing through alternate periods of desiccation. At times desiccation pro- 

 ceeded to such a point as to. cause concentration of the lake waters and deposits of 

 salt. More than likely each salt bed was marked by the- evaporation of the lake and 

 the formation of a salt playa. 



RAILROAD VALLEY. 



Railroad Valley is in the northeastern part of Nye County, Nev., about 130 miles 

 northeast of Tonopah and 80 miles southwest of Ely. It is 10 to 20 miles wide from 

 east to west and somewhat over 100 miles long north to south. The flat, central por- 

 tion of the valley has an area of about 200 square miles. The drainage basin is about 

 6,000 square miles. Free states that shore-line indications show a lake level varying 

 from 50 to 300 feet above the present bed of the dry lake. A number of playas, 

 covered by thin salt crusts, occupy the bed of the present dry lake. (Plate IV, fig. 2.) 

 Analyses of these crusts and the accompanying brines have been given in a previous 

 section, and many of them show a high potassium content. The Railroad Valley 

 Co. put down a bore 1,204 feet deep on the east-west half-section line of sec. 2, T. 8 N., 

 R. 56 E. The bore is about one-fourth mile west of the west north-south line of seel, 

 same T. The log of the bore is herewith presented. 



Log of potash drill hole No. 1, Railroad Valley, Nye County, Nev. 



[Drilling commenced Mar. 17, 1912; ceased Aug. 27, 1912. All operations in charge of D. H. Walker.] 



Feet. 



Mixed clay and sand, mostly sand (fresh water, not artesian) 1-32 



Quicksand (fresh water) 32-103 



White clay 103-104 



Alternations of quicksand and clay. Some fine gravel among the quick- 

 sand (artesian waters in sands, especially at 128 feet) 104-136 



Clay 136-178 



Very fine quicksand (artesian water, especially at top of division) 178-214 



Clay 214-220 



Quicksand with fine gravel (artesian water) 220-222 



Rapid alternations of sand and brownish clays (artesian water in most of 



the sands, especially at 250 feet) 222-255 



Clay 255-260 



Quicksand 260-264 



