CHARACTER OF CORE FROM 'SlEYER 6" WELL 



441 



AboAng) and there is a great abundance of small fragments of iron from 

 the pipe. 



The chemical composition of this core is shown in Table II. The 

 amount of metallic iron was so high as to render useless Pratt's method 

 for the determination of FeO. It was not found practicable to remove 

 this iron with the electromagnet. The greater part of the error of 

 analysis here undoubtedly devolves on the determination of metallic iron. 

 Check determinations of the total iron were made and were in satisfac- 

 tor}' agreement. From these the amount of FeO in the fusion was calcu- 

 lated by subtracting the metallic iron, expressed as FeO, from the total 

 iron as FeO. Considerations similar to those given in connection with 

 the Montezuma core lead us to believe that there is no ferric iron present. 



Table II. — Fused Core, "Meyer 6" Well, Santa Fe Springs, Los Angeles 



County, California 



12 3 4 



SiOa 65.45 65.11 68.95 68.16 



AI2O3 14.35 14.28 15.12 14.95 



FejOs none none none . 95 



FeO 4.67 4.65 4.92 2.92 



Fe 5.60 5.57 



MgO 0.86 0.85 0.90 1.58 



CaO 2.48 2.47 2.62 2. .32 



Na^O 3.52 3.50 3.71 4.13 



K2O 2.90 2.88 3.06 2.89 



H.O+ 0.13 1 11.36 



H2O— 0.05 1 ^-^'^ ^-^^ 1 0.30 



CO2 none none none 



TiO, 0.30 0.30 0.31 0.90 



P2O5 0.21 0.21 0.22 none 



S p. n. d. p. n. cl. p. n. d. .... 



FeS, .... 0.03 



MnO p. n. d. p. n. d. p. n. d. none 



Sum 100.52 100.00 100.00 100.49 



1. Composition of sample. M. Anrousseau. analyst. 



2. The same, calculated to 100. 



3. Composition of fused sedimentary material calculated from 1 by deduct- 

 ing metallic iron and reducing to 100. 



4. Aplite, Zeia River, Amnr District, Siberia. W. Giers, analyst. E. Ahiiert, 

 Expl. G. Reg. Aurif. Sib., X, Taf. VII, 1910. 



The chemical analysis, recalculated by deducting metallic iron to de- 

 termine the actual composition of the rock matter (Table II, number 3), 

 confirms the indications of the microscope that the rock was of the nature 



