The Geology and Petrography of Crater Lake National Park, 1902
PART II.
BASALTS.
CHEMICAL ANALYSES OF BASALTS.
The following analyses were made in the United States Geological Survey laboratory:
Analyses of Crater Lake basalts.
[Analyses by H. N. Stokes.]
| 158. | 173. | 189. | |
| SiO2 | 56.95 | 52.99 | 58.65 |
| Al2O3 | 18.84 | 16.71 | 18.35 |
| Fe2O | 2.06 | 3.80 | 1.59 |
| FeO | 4.28 | 3.55 | 4.21 |
| MgO | 4.37 | 6.95 | 3.49 |
| CaO | 7.45 | 8.49 | 6.95 |
| Na2O | 3.89 | 3.56 | 3.70 |
| K2O | .82 | 1.29 | 1.32 |
| H2O- | .19 | .18 | .20 |
| H2O+ | .31 | .59 | .70 |
| TiO3 | .79 | 1.18 | .81 |
| ZrO2 | —- | None. | —- |
| CO2 | None. | None. | None. |
| P2O5 | .19 | .42 | .17 |
| SO3 | —- | None | None. |
| Cl | —- | Trace. | —- |
| F | —- | Undet. | —- |
| S | Trace. | None. | None. |
| Cr2O3 | None. | None. | None. |
| NiO | —- | .02 | —- |
| MnO | Trace. | Trace. | Trace. |
| BaO | .04 | .07 | .06 |
| SrO | Trace. | .12 | Trace. |
| Li2O | None. | None. | None. |
| Total | 100.18 | 99.92 | 100.20 |
| NOTE.—O=Cl.No. 158. A hypersthene-bearing basalt of the interstitial type, from Anna Creek. See page 145.
No. 173. Hypersthene-bearing basalt, porphyritic interstitial type, transitional to the andesitic type, from the base of Red Cone. See page 155. No. 189. A hypersthene—bearing basalt of the andesitic type, from north of Desert Cone. This rock is doubtfully placed among the basalts, based upon structural and geological relationships. See page 160. |
|||
